new exam 3 set 11
Explain what a resting potential is, and list four factors that contribute to the maintenance of the resting potential.
The difference in charge across a neurons membrane when it is not communicating with other cells. 1. A different concentration of ions allows the gradient to exist, the phospholipid bilayer prevents ions from crossing. 2. Ion Channel - a protein in the pore that selectively allows ions to pass through 3. Ions can be carried across via cotransporter proteins, with another ion that diffuses along it's gradient. 4. Pumped against an electrochemical gradient by a membrane protein that hydrolyzes ATP.
a given photon of light may trigger an action potential with thousands of times more energy. how is this signal strength magnified?
by an enzymatic reaction
autonomic nervous system
carries out INVOLUNTARY responses, not under conscious control smooth muscle, cardiac muscle, and glands are effectors
somatic nervous system
carries out VOLUNTARY responses, under conscious control skeletal muscles are the effectors
sensory neurons
carry information to the CNS
sensory neurons
carry information to the brain and spinal cord
depolarization
means that the membrane becomes less polarizes than before- moves from highly negative toward 0 then is briefly positive
Deafness caused by loud sounds often results from damage to which receptor cells?
mechanoreceptors
What are some examples of positive feedback and negative feedback?
rise in blood ph triggers effectors that act to reduce the rise
hygiene hypothesis
idea that autoimmune and allergic responses arise in individuals who, because of hygiene practices, have experienced less exposure to pathogens and parasites
True or False: All prokaryotic cells have peroxisome
True
Focusing occurs by changing the shape of the a. Cornea b. Iris c. Fovea d Lens
d Lens
cytokines
"cell-movers"... most amplify the response of a cell to a stimulus
attenuated viruses
"live" viruses, consist of the complete virus particles that infect cells smallpox and measles
Chapter 43 - Animal Nervous System
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Chapter 45 - Animal Movement
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Chapter 46 - Chemical Signals in Animals
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Chapter 47 - Animal Reproduction and Development
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Chapter 48 - The Immune System in Animals
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how many TLR's have been identified in humans?
11 - enough to detect virtually any type of invasion in humans
IPSP
Inhibitory postsynaptic potentials -changes in postsynaptic cell that makes the membrane potential more negative
Write in: A negative feedback loop _____ a response by reducing the initial stimulus
Inhibits
neuroendocrine signals
(neurohormones) are hormones released from neurons
Write in: A cell is required to synthesize more insulin receptors. Describe the process of synthesis processing and ultimate relocation of insulin receptor of the cell
(will edit) 1. Gene for receptor is in the nucleus 2. Transcription of gene results in mRNA 3. mRNA goes into cytoplasm 4. Message is ready by ribosome on rough ER 5.Receptor protein is sent to golgi for packaging 6. Receptor protein is sent out to cell membrane
Match the pairs (list the monomer first!) a. fatty acids b. Polypeptides/Proteins c. Lipids d. Amino Acids e. Monosaccharides f. Carbohydrates g. Nucleic Acids e. Nucleotides
- A to C - D to B - E to F - E to G
hormone receptors
proteins that hormones bind to in target tissues
True or False: Diffusion ALWAYS involves a substance moving down its concentration gradient
True
A red blood cell is traveling in an artery located in the left arm. How many capillary beds will the red blood cell travel through before it reaches the left ventricle?
2
what do the genes for the light chains and heavy chains have have?
---Light Chain -40 different V segments -5 different J segments -a single C segment ---Heavy Chain -51 different V segments -6 different J segments -a single C segment -27 different D segments
what does the BCR protein consist of?
-2 light chains = smaller polypeptides -2 heavy chains = larger polypeptides heavy chain is about two times the size of the light chain each BCR has two light and two heavy chains held together by disulfide bonds
what is the typical membrane potential between resting neurons?
-65 to -80 mV
how are T-cells activated by antigen-presenting cells?
-CD4 T cells interact with class II MHC-bound epitopes -CD8 T cells interact with class I MHC-bound epitopes
what are the two types of T cells?
-CD4+ = CD4 proteins -CD8+ = CD8 proteins
Describe the function and location of each type of supporting cell
-Na+/K+-ATPase pumps Na+ out and K+ in the cell membrane -K+ ions travel out of the cell through K+ leak channels in the cell membrane
what are the 2 different types of helper T-cells?
-TH1 - help activate cytotoxic T cells -TH2 - help activate B cells
Describe two mechanisms by which a neurotransmitter affects the postsynaptic cell
-When a neurotransmitter binds to a ligand-gated ion channel, the channel opens and allows a flow of ions -some bind to receptors that activate enzymes for production of a second messenger
skeletal muscle is voluntary and must be stimulated by somatic motor neurons
...
innate immunity vs. adaptive immunity
-cells that are always ready -cells that must first be selectively activated to tailor their response against a specific pathogen
what do days 15-21 consist of the menstrual cycle?
-corpus luteum develops from the remains of the ruptured follicle, secretes large amounts of progesterone -rise is progesterone inhibits secretion of LH and FSH and activates the thickening of the uterine lining
what are the roles of dendrites and axons?
-dendrites - receive signals from axons of other neurons -axons - send signals to dendrites and cell bodies of other neurons ALLOW for communication between neurons
how do our bodily openings protect themselves from pathogen entry?
-eyes - blinking wipes tears across the eyes, which contain lysozyme, an antibacterial enzyme -ears - hairs and earwax trap pathogens in the EAC -nose - nasal passages are lined with mucous secretions and hairs trap pathogens -digestive tract - pathogens are trapped in saliva and mucous and then swallowed, most are destroyed by the low pH of the stomach
what do days 8-14 consist of the menstrual cycle?
-follicle grows, secretion of estradiol increases, increases cell number in uterine lining because of mitosis -estradiol begins to exert positive feedback on LH secretion -positive feedback results in a spike in the LH level -LH spike triggers ovulation
what do days 22-28 consist of the menstrual cycle?
-if fertilization does NOT occur then the corpus luteum degenerates -progesterone levels fall as the corpus luteum shrinks -the thickened walls of the uterus degenerate, causes the bleeding of the menstrual cycle --> MARKS THE START OF THE NEXT CYCLE -GnRH, LH, FSH are released because of progesterone -FSH levels rise, new menstrual cycle begins
what can a sodium-potassium move when they gain one molecule of ATP?
-moves 3 Na+ ions out of the cell -moves two K+ ions into the cell
Explain how neurons can be classified by function
-sensory neurons- in the skin, eyes, ears, mouth, and nose which transmit information about the environment. Inside the body they monitor conditions that are important in homeostasis like pH and temperature. -inter-neurons- pass signals from one neuron to another -motor neurons-send signals to effector cells in glands or muscles, motor neurons and sensory neurons are bundled together into long tough strands of nerves called tissues
List and describe the three major parts of a neuron, and explain the function of each
-the cell body/ soma-contains the nucleus -dendrites- receive signal from the axons of different cells -axon-sends signal to dendrites and cell bodies of other neurons
what do days 1-7 consist of the menstrual cycle?
-the uterus sheds its lining, a follicle develops in one ovary because of FSH -follicle secretes estradiol and some progesterone -estradiol suppresses LH secretion through negative feedback
what are the two reasons why the immune system rejects foreign cells?
-they contain nonself molecules -they don't contain self molecules
active transport via Na+/K+-ATPase ensures that eventually the concentration of K+ is much higher on the inside of the plasma membrane than outside, while the concentration of Na+ is lower inside than outside
...
many of the hormones produced by the anterior pituitary stimulate the production of other hormones
...
neuron has negative resting potential because the Na+/K+-ATPase pumps 3 cations out for only 2 cations in, and because K+ exits the neuron thru leak channels along its electrochemical gradient
...
sensory information from receptors in the PNS is sent to the CNS, where it is processed. Then a response is transmitted back to appropriate parts of the body via motor neurons
...
hormones coordinate the activities of cells in 3 arenas:
1) development, growth, reproduction 2) response to environmental challenges 3) maintenance of homeostasis
immune system
1) prevent the entry of potential pathogens 2) detect the presence of a pathogen by distinguishing it from the animal's own body 3) eliminate the pathogen
A sperm stem cell is progressing through meiosis. A non-disjunction event occurs during meiosis II on chromosome 21. One of the daughter gametes has two copies of chromosome 21 and the other has no copies of chromosome 21. The sperm with no copies eventually fertilizes a normal egg. The zygote that is formed will have ______ copy/copies of chromosome 21 and will eventually _________.
1, die during the pregnancy
Describe two ways to increase the effectiveness of nerve transmission
1- Cations move more quickly down large axon diameters 2-Myelination affects speed- oligodendrocytes or Schwann cells wrap around axon, forming a myelin sheath, which acts as electrical insulation. This prevents charged ions from leaking out the membrane. Electrical signals jump between nodes at unmyelinated sections much faster than if the whole thing were unmyelinated.
Explain how the action potential is propagated along a neuron
1- Na+ enters the neuron and repels intercellular cations, causing them to spread away from Na+ channels. 2- As the positive charges move away from the Na+ channels, they depolarize adjacent portions of the membrane 3- Nearby Na+ channels open when the membrane reaches threshold, resulting in action potential
What is the correct order? 1 - Motor neuron gets signal from brain and send it to motor end plate 2 - Myosin-binding sites are uncovered 3 - Calcium leaves SR and enters free cytoplasm 4 - Troponin changes shape and moves off of troponin 5 - Motor neuron releases acetylcholine 6 - Calcium binds to troponin 7 - Myosin binds to actin results in power stroke to pull actin towards M-Line 8 - Acetylcholine binds to receptors 9 - Acetycholine stimulates skeletal muscles by traveling through the T-tubule into the sarcoplasmic reticulum
1-5-8-9-3-6-4-2-7-1
Describe synaptic transmission across an electrical synapse and a chemical synapse
1-Action potential reaches end of axon 2- Depolarization created by action potential opens Ca2+ channels, causing the ion to flow into the presynaptic cell 3-Synaptic vesicles fuse with the membrane and release neurotransmitters into the synaptic cleft 4-Neurotransmitters bind to receptors on postsynaptic cell, causing changes in membrane potential, triggering action potential 5-Neurotransmitters are reabsorbed by presynaptic cell
List three criteria for a compound to be considered a neurotransmitter
1-must be present at synapse and release in response to potential 2-bind to a receptor on a postsynaptic cell 3-be taken up or degraded
Describe synaptic transmission across an electrical synapse and a chemical synapse.
1. Action potential reaches end of axon. 2. Depolarization created by action potential opens Ca²⁺ channels, causing the ion to flow into the presynaptic cell. 3. Synaptic vescicles fuse with the membrane and release neurotransmitters into the synaptic cleft. 4. Neurotransmitters bind to receptors on postsynaptic cell, causing changes in membrane potential, triggering action potential. 5. Neurotransmitters are reabsorbed by presynaptic cell.
Be able to trace the excitatory events starting from the release of acetylcholine at the motor neuron synapse and ending with muscle contraction. You should know the pathway of depolarization of the muscle cell, how this leads to calcium release, and how the calcium in the myofibril leads to muscle contraction.
1. Action potential releases the neurotransmitter acetylcholine (ACh) 2. ACh binds to receptors on plasma membrane of muscle cell, causing membrane depolarization. 3. Depolarization causes action potential in the fiber, which travels through via T tubules. 4. When action potentials reach sarcoplasmic reticulum, calcium channels open. 5. Calcium binds to troponin, allowing contraction.
Describe two ways to increase the effectiveness of nerve transmission.
1. Cations move more quickly down large axon diameters. 2. Myelination affects speed - oligodendrocytes or Schwann cells wrap around axon, forming a myelin sheath, which acts as electrical insulation. This prevents charged ions from leaking out the membrane. Electrical signals jump between nodes at unmyelinated sections much faster than if the whole thing were unmyelinated. Multiple Sclerosis results when the immune system targets oligodendrocytes in the CNS
List and describe the three major parts of a neuron, and explain the function of each.
1. Cell body/Soma - contains the nucleus 2. Dendrites - receives signal from the axons of different cells. 3. Axon - sends a signal to dendrites and cell bodies of other neurons
Centrosome 1. Function 2. Prokaryote? 3. Eukaryote? 3a. Plant? Animal? Both?
1. Contains centriole (MTOC) 2. Prokaryote = Absent 3. Eukaryote = Present 3a. Animal only (plants have something similar)
Chromatin 1. Function 2. Prokaryote? 3. Eukaryote? 3a. Plant? Animal? Both?
1. DNA+Histone 2. Prokaryote = Present (1 circular chromosome) 3. Eukaryote = Present 3a. Both (animal+plant)
Central Vacuole 1. Function 2. Prokaryote? 3. Eukaryote? 3a. Plant? Animal? Both?
1. Fills with water to maintain cell shape, stores sugar 2. Prokaryote = Absent 3. Eukaryote = Present 3a. Plants only
3 ways to decrease surface area:volume ratio
1. Flattening - fish gills have structures called lamellae 2. folding - intestinal folds and villi 3. branching - capillaries branch out across an organism
If the bacteria is purple 1. What is result of Gram stain? 2. What does this mean? 3. And ff bacteria is pink?
1. Gram + 2. Thick cell wall (loaded with peptidoglycan) 3. Gram-, thin cell wall
Nitrogen Fixation 1. What structure is responsible for this? 2. Structure is found in what cells? 3. What is nitrogen fixation?
1. Heterocyst 2. found in Nostoc cells 3. Nitrogen is taken out of environment and used to build proteins.
Nucleus 1. Function 2. Prokaryote? 3. Eukaryote? 3a. Plant? Animal? Both?
1. Houses DNA and protects genes 2. Prokaryote = Absent 3. Eukaryote = Present 3a. Both (animal+plant)
Mitochondria 1. Function 2. Prokaryote? 3. Eukaryote? 3a. Plant? Animal? Both?
1. Make ATP out of glucose 2. Prokaryote = Absent 3. Eukaryote = Present 3a. Both (animal+plant)
Ribosomes 1. Function 2. Prokaryote? 3. Eukaryote? 3a. Plant? Animal? Both?
1. Make proteins 2. Prokaryote = Present 3. Eukaryote = Present 3a. Both (animal+plant)
Rough Endoplasmic Reticulum 1. Function 2. Prokaryote? 3. Eukaryote? 3a. Plant? Animal? Both?
1. Makes proteins, distributes transport vesicles, membrane factory 2. Prokaryote = Absent 3. Eukaryote = Present 3a. Both (animals+plants)
Explain how the action potential is propagated along a neuron.
1. Na⁺ enters the neuron and repels intercellular cations, causing them to spread away from Na⁺ Channels. 2. As the positive charges move away from the Na⁺ channels, they depolarize adjacent portions of the membrane. 3. Nearby Na⁺ channels open when the membrane reaches threshold, resulting in action potential.
Fill in: The ______ nervous system brings information into and out of the brain and a nerve cord while the ________ nervous system is where integration takes place including the brain and .a nerve cord
1. Peripheral Nervous System 2. Central Nervous System
Chloroplast 1. Function 2. Prokaryote? 3. Eukaryote? 3a. Plant? Animal? Both?
1. Photosynthesis (make glucose from sunlight and oxygen) 2. Prokaryote = Absent 3. Eukaryote = Present 3a. Plants only
Golgi Apparatus 1. Function 2. Prokaryote? 3. Eukaryote? 3a. Plant? Animal? Both?
1. Proteins folded into 3D shape, packaged, and placed into vesicles to be delivered around cell. 2. Prokaryote = Absent 3. Eukaryote = Present 3a. Both (animal+plant)
Cell Wall: 1. Function 2. Prokaryote? 3. Eukaryote? 3a. Plant? Animal? Both?
1. Provides structure & Protection 2. Prokaryote = Present 3. Eukaryote = Present 3a. Both (plant/animal)
Write in: Explain the 5 stages of an action potential
1. Resting State: voltage gated sodium and potassium channels are closed (although potasium leak channels and sodium-potassium pump is still going). Voltage in the cell is about -70mV 2. Depolarization: A stimulus (e.g., neurotransmitter binds to a ligand receptor) act on the neuron and opens a sodium channel which results in the inner membrane charge becoming more positive. Once the charge hits about -55 mV, the voltage threshold is reached. 3. Once threshold is reached, more sodium channels open allowing sodium to rush into the cell causing the cell to become positively charged (no more than +30mV). This is the rising phase of an action potential. 4. After the peak of the action potential, voltage-gated sodium channels inactivate and voltage-gated potassium channels open. Sodium no longer is rushing in and instead, potassium flows out of the cell causing the voltage within the cell to drop and become more negative. This is the falling phase of an action potential. 5. After an action potential, the charge of the neuron does not stop at the resting potential because membrane permeability to K+ is at first higher than resting potential. This causes the voltage to "undershoot" the resting potential voltage (around -75mV) and then voltage-gated potassium channels close and resting potential is then restored.
Plasma Membrane 1. Function 2. Prokaryote? 3. Eukaryote? 3a. Plant? Animal? Both?
1. Selectively permeable membrane 2. Prokaryote = Present 3. Eukaryote = Present 3a. Both (plant/animal)
3 components of homeostasis
1. Sensor - structure that senses some aspect of the external or internal environment 2. integrator - evaluates sensory information and decides whether a response is necessary to achieve homeostasis 3. Effector - any structure that helps restore the desired internal condition
List all of the structures of a neuron as well as one function for each structure.
1. Soma (aka cell body): contains nucleus and most organelles, synthesizes neurotransmitters. 2. Dendrites (branch off of soma): Receive signals from other neurons 3. Axon Hillock (part of soma where axon meets soma): After processing incoming signals from other neurons, axon hillock "decides" if impulse should be sent down axon and sent to another neuron. 4. Axon: Extends from soma, transmits signals away from cell body and to other cells 5. Nodes of Ranvier (gaps in myelin sheath along axon): Where action potentials are formed along the axon, contain voltage-gated Na+ channels, action potentials jump between nodes down the axon. 6. Myelin Sheath (along axon): insulate axon and increases speed of action potential (made by glia-oligodendrocytes and Schwann cells) 7. Schwann Cell (found in middle of myelin sheath): breaks down old myelin and secretes new myelin (in Peripheral Nervous System) 8. Terminals (aka synaptic bulbs; branch off axon): stores neurotransmitters that diffuse across synaptic cleft if action potential reaches it. 9. Synapse (Space between presynaptic terminals and post-synaptic dendrites): The space where neurotransmitters are released into before meeting ligand receptors in post-synaptic dendrites.
Smooth Endoplasmic Reticulum 1. Function 2. Prokaryote? 3. Eukaryote? 3a. Plant? Animal? Both?
1. Synthesize lipids in cell, makes steroid hormones, stores calcium, detoxifies drugs/poisonsmetabolizes carbs 2. Prokaryote = Absent 3. Eukaryote = Present 3a. Both (animals+plants)
List three criteria for a compound to be considered a neurotransmitter.
1. must be present at synapse and release in response to potential 2. Bind to a receptor on a postsynaptic cell 3. Be taken up or degraded.
Explain how neurons can be classified by function.
1. sensory neurons- in skin, eyes, ears, moth, and nose transmit info about the environment. inside the body they monitor conditions that are important in homeostasis, such as blood pH and temp. 2. inter-neurons- pass signals form one neuron to another 3. motor neurons-send signals to effector cells in glands or muscles--motor neurons and sensory neurons are bundled together into long tough strands of nerves called tissues
what are the 4 steps of myosin interacting with ATP?
1.) ATP binds to the myosin head, the head releases from the actin 2.) ATP is hydrolyzed to ADP and inorganic phosphate, the head then binds to a new actin further down the thin filament 3.) inorganic phosphate is released, and the neck is bent back to its original conformation 4.) ADP is released, and the myosin head is ready to bind to another ATP molecule
what are the 4 steps in B-cell activation?
1.) B-cell recognizes the invader and binds to an epitome on the antigen, the antigen is then internalized and processed 2.) B-cell stimulates helper T-cell, MHC-peptide complex on the B-cell surface interacts w/ receptors on the T-cell surface 3.) B-cell is activated by the helper T-cell, cytokines from the activated helper T-cell activate the B-cell 4.) B-cell gets to work, the activated B-cell replicates and some daughter cells differentiate into plasma cells, which produce large quantities of antibodies
what are the three steps of action potential propagation?
1.) Na+ enters the axon, bringing negative charges and repelling positive charges 2.) the charge spreads, and the downstream membrane begins to depolarize 3.) downstream voltage-gated channel opens, causing a new action potential in the new location
what are the steps of what happens when action potentials from a motor neuron arrive at a muscle cell?
1.) acetylcholine is released from the motor neuron 2.) ACh diffuses across the synaptic cleft and binds to receptors on the membrane of the muscle cell 3.) the action potentials spread across the membrane and into the cell via the T tubules 4.) the action potential travels through the T tubules and into the sarcoplasmic (endoplasmic) reticulum, a protein then opens calcium channels and calcium diffuses and enters the cytoplasm 5.) calcium travels and binds to the troponin, freeing the myosin binding sites
what are the four characteristics of the adaptive immune system?
1.) specificity - antibodies and other components can only adapt to specific sites on specific antigens 2.) diversity - can recognize and respond to almost any type of antigen 3.) memory - responses are stronger and quicker when an individual is exposed to antigens from previous infections 4.) self-nonself recognition - can distinguish between self molecules and nonself molecules (antigens)
what are the five stages of the model of synaptic transmission?
1.) action potential arrives near the synaptic cleft 2.) voltage-gated Ca^2+ channels open and they enter the presynaptic cell 3.) synaptic cells fuse w/ the presynaptic membrane, release neurotransmitters 4.) ion channels in the postsynaptic membrane open when neurotransmitters bind to receptors, flow of ions cause change in the potential of the postsynaptic membrane 5.) the ion channels in the postsynaptic membrane close when the neurotransmitters unbind from receptors
what are the 2 divisions of the PNS?
1.) afferent division 2.) efferent division
what are the two major parts of the myosin "head"?
1.) an ACTIN binding sight 2.) an ATP binding sight
clonal selection theory
1.) antigens are recognized by receptors on B cells and T cells 2.) lymphocytes require receptor-epitome binding to become activated 3.) active lymphocytes are clones 4.) active lymphocytes endure
what are the 6 steps of an inflammatory response?
1.) bacteria and other pathogens enter the wound 2.) platelets from the blood release blood-clotting proteins at the wound site 3.) injured tissues and macrophages at the site release chemokines, which recruit immune system cells to the site 4.) mast cells at the site secrete histamine and other factors that dilate surrounding blood vessels, making them more permeable 5.) neutrophils are recruited to remove pathogens by phagocytosis 6.) other recruited leucocytes mature into macrophages that phagocytize pathogens and secrete key signaling molecules
what are the two responses by the adaptive immune system to remove foreign invaders?
1.) cell mediated response - promoted by TH1 cells, activates phagocytic and cytotoxic T-cells, cell-cell contact 2.) humoral response - promoted by TH2 cells, production of antibodies and other proteins secreted into the blood and lymph
what are the two contributors to the potential energy of a membrane potential?
1.) charges 2.) concentrations of ions
what are the three main processes that cortisol uses to maintain glucose production?
1.) cortisol induces the synthesis of liver enzymes that make glucose 2.) cortisol makes adipose tissue (fat tissue) and resting muscles resistant to insulin - reserves glucose 3.) cortisol promotes the release of fatty acids from adipose tissue - they are then used by the heart and muscles
how are intracellular pathogens eliminated?
1.) cytotoxic T-cells recognize and bind to infected cells 2.) T-cell vesicles secrete proteins that form pores that allow other proteins to pass through the pores of the cytoplasm of the affected cell 3.) apoptosis occurs, causing the infected cell to break up, meanwhile phagocytic cells consume the fragments, eliminating the intracellular pathogens
what are the 5 steps of how dendritic cells process protein antigens and load peptide fragments onto class II MHC proteins?
1.) dendritic cell ingests the antigen via phagocytosis 2.) enzymes break antigen proteins into peptide fragments 3.) peptide fragments are loaded onto class II MHC proteins in endosomes 4.) MHC protein presents peptide fragment on the cell surface
what are the three distinct phases of action potentials?
1.) depolarization 2.) repolarization 3.) hyperpolarization
what are the three events that sex hormones play a key role in?
1.) development of the reproductive tract and brain in embryos 2.) maturation of the reproduction tract during adolescents 3.) regulation of spermatogenesis and oogenesis in adults
what are the three arenas that hormones coordinate the activities of cells through?
1.) development, growth, and reproduction 2.) response to environmental challenges 3.) maintenance of homeostasis
what two hormones are needed to interact for the metamorphosis to occur in insects?
1.) juvenile hormone (JH) - levels are high, when they become low metamorphosis completes 2.) ecdysone - induces the growth of the larva via molting, when JH levels are low, it induces a complete remodeling of the body
what are the two types of movements of an animal?
1.) movement of the entire animal relative to its environment 2.) movement of one part of the animal relative to other parts (not involved in locomotion)
what are the two basic types of nervous systems that neurons organize into?
1.) nerve net 2.) central nervous system
what are the four ways that bound antibodies interfere with infection?
1.) opsonization - antibodies coat pathogens, prepare to be destroyed 2.) neutralization - coated pathogens are blocked from interaction/infecting host cells 3.) agglutination - antibodies cause antigens to clump together, makes these cells and viruses not able to affect the cells of the body, and become easy targets for phagocytes 4.) co-stimulation of compliment proteins - cause compliment systems to kill the antibody-bound pathogens
what are the two divisions of the autonomic nervous system?
1.) parasympathetic nervous system 2.) sympathetic nervous system
what are the three key processes of the immune system?
1.) preventing the entry of potential pathogens 2.) detecting the presence of a pathogen by distinguishing it from the animal's own body 3.) eliminating the pathogen
what are the three ways ions cross plasma membranes?
1.) primary active transport 2.) secondary active transport 3.) ion channel
what do T-cells require other cells for?
1.) process the antigen 2.) present the antigens to the TCR's
what are the three components that a homeostatic system depends on?
1.) sensory receptor 2.) integrator 3.) effector cells
what are the three types of muscle tissue?
1.) smooth muscle tissue 2.) cardiac muscle tissue 3.) skeletal muscle tissue
what are the three parts of a neuron?
1.) soma (cell body) 2.) dendrites - a highly branched group of relatively short projections - 2 mm long 3.) axons - relatively long projections - up to 1 m long
what are the two divisions of the efferent division?
1.) somatic nervous system 2.) autonomic nervous system
what are the 4 steps in the random recombination of V and J segments?
1.) start with DNA encoding the light chain 2.) DNA segments recombine - J and V segments are combined, then join a C segment 3.) Transcription and RNA processing occur - removing introns 4.) translation - results in a protein with a unique amino acid sequence
what are the two hormones that human testes produce?
1.) testosterone 2.) Müllerian inhibitory substance - polypeptide hormone
what are 2 important points of the orientations of the C and V regions of light and heavy chains?
1.) the V regions of light and heavy chains in a BCR are adjacent to each other, and face away from the membrane 2.) TCRs also have V and C regions, which are arranged like those in BCRs
what does the force output of skeletal muscles depend on?
1.) the proportion of different fiber types 2.) the organization of fibers within the muscle 3.) how the muscle is used
what are the two thyroid hormones (hormones produced by the thyroid gland)?
1.) triiodothyronine - T3 2.) thyroxine - T4 both are derived from the amino acid tyrosine, but are LIPID SOLUBLE
millivolt (mV)
1/1000 of a volt
how many estimated different BCR and TCR segments can be produced?
10^10 - 10^14
what is the relationship between taste cells and number of expressed receptor types?
1:1
In metaphase of mitosis, each chromosome is attached to ____ spindle pole(s). In metaphase of meiosis I, each chromosome is attached to ____ spindle pole(s).
2, 1
Write in: Whenever you alter a protein (e.g., bind or remove), you change the ________ which then changes its _________.
3-D Conformation (structure); behavior
how many epinephrine (adrenaline) receptors are there?
4 - two alpha receptors and two beta receptors -- all are found in different types of tissues and include a different response tells us that THE SAME HORMONE CAN TRIGGER DIFFERENT EFFECTS IN DIFFERENT CELLS
How much bigger would an axon have to be to double velocity? λ=√ dRm/4Rl 2x 3x 4x 8x
4x the diameter
which of the following is the correct sequence that occurs during the excitation and contraction of a muscle cell?
5 3 2 1 4
Which of the following is the correct sequence that describes the excitation and contraction of a skeletal muscle fiber? 1. Tropomyosin shifts and unblocks the cross-bridge binding sites. 2. Calcium is released and binds to the troponin complex. 3. Transverse tubules depolarize the sarcoplasmic reticulum. 4. The thin filaments are ratcheted across the thick filaments by the heads of the myosin molecules using energy from ATP. 5. An action potential in a motor neuron causes the axon to release acetylcholine, which depolarizes the muscle cell membrane.
5 → 3 → 2 → 1 → 4
Place the following steps in the correct order (power stroke) 1 - ATP hydrolyzed 2 - ADP and Inorganic phosphate (Pl) are produced and remain bound to myosin 3- Myosin head attaches to actin filament to pull it toward middle of sarcomere 4 - Conformational change in myosin head 5 - Power stroke is triggered - myosin head releases its bound ADP 6 - Myosin head slides to and binds to new site on the actin filament 7 - Myosin binds to ATP causing myosin to be released from actin filament 8 - Pl Is released
7-4-1-2-6-8-5-3
A species of worm has a diploid chromosome number of 16. Therefore, it produces gametes that contain __________ chromosomes.
8
True or False: Feedback mechanisms control hormone signaling
True
True or False: Glucose requires a carrier transport protein (the ferry boat) to enter cell.
True
Once an action potential has been triggered, the first major change in the neuron is
A local reversal of membrane polarity, with the interior of the cell becoming more positive
The fluid mosaic model describes the plasma membrane as consisting of
A phospholipid bilayer containing proteins able to move laterally in the membrane
Cell A has a radius of 20 microns. Cell B has a radius of 10 microns. Compared to Cell B, Cell A has
A smaller surface:volume Ratio
Define tissue and explain where it falls in the hierarchy of structural organization.
A tissue is a group a cells that function as a unit. Atomic/molecular level > cellular level > tissue level > organ level > organ system level > organism level
Select all that apply: Which of the following structures are found in BOTH plant and animal eukaryotic cells? a. Nucleus b. Golgi apparatus c. Rough ER d. Smooth ER e. Central Vacuole f. Peroxisome g. Mitochondrion h. Plasma Membrane i. Cell Wall j. Cytoskeleton k. Centrosome L. Ribosomes m. Chloroplasts n. Plasmodesmata
A, B, C, D, F, G, H, J, L Nucleus, Golgi, ER, Peroxisome, Mitochondrion, Plasma membrane, cytoskeleton, ribosomes Animals only: centrosome (plants have something similar) Plants only: Central vacuole, cell wall, chloroplasts, plasmodesmata
SELECT ALL THAT APPLY: What are the signaling systems in the body? a. paracrine b. Autocrine c. Eukarocrine d. Nervous System e. Exocrine f. Phosphocrine g. Cell-Cell Contact Dependent h. Endocrine
A, B, D, E, G, H (Paracrine, Autocrine, Exocrine, Endocrine, Nervous System, Cell-Cell Contact Dependent)
In the stereotypical neuron shown in the diagram below, which of the following could lead to the generation of action potentials in the post-synaptic neuron? [More than one answer may be correct.] Image credit: BruceBlaus - CC BY 3.0, https://commons.wikimedia.org/w/index.php?curid=28761830 A. Opening Na+ channels in the plasma membrane of a dendritic branch. B. Opening Cl- channels in the plasma membrane of a dendritic branch. C. Opening Na+/K+ channels in the plasma membrane of a dendrite. D. Opening Na+ channels in the plasma membrane of the cell body.
A, C, and D
The ductus arteriosus
allows blood to travel from the pulmonary artery to the aorta
Fill in: Each muscle __A__ is made up cylinders called __B__, structures that are organized into contractile units called )__C__.
A. Fiber B. myofibrils C. Sarcomeres
Main muscle responsible for for a movement is called ________ and the muscle that opposes it is the ________
Agonist; antagonist
Select ALL that apply: What are the functions of protein? a. Structural support b. Storage c. Transport d. Cellular communications e. Movement f. Defence against foreign substances
All of these are functions of proteins
What is the relationship between each part of the sarcomere (Z line, A band, I band, H zone).
Aband-middle area in the sarcomere where thick and thin filaments are found I band-Lighter contains thin filaments but no thick filament Z disc-separate one sarcomere from the next H zone-area of only thick filaments
Select all that apply: What can affect protein structure a. Primary structure b. Physical conditions c. Chemical conditions d. Alterations to pH e. Temperature f. Salt concentration g. Environmental factors
ALL of these can affect protein structure!
In muscle cells, myosin molecules continue moving along actin molecules as long as
ATP is present and intracellular Ca2+ is high.
Which of the following would prove that a substance enters a cell using active transport and NOT passive transport?
ATP is required for movement of the substance into the cell.
What prevents action potentials from moving backward along the axon? Absolute refractory period Relative refractory period Myelination provides resistance across the membrane Voltage-gated channels can only operate in the direction of propagation
Absolute refractory period
Order the sequence of events following an action potential in a presynaptic neuron that leads to an action potential in a postsynaptic neuron. Action potential depolarizes pre-synaptic neuron. Vesicles release neurotransmitter molecules. Neurotransmitter molecules diffuse into the synapse. Neurotransmitter molecules bind to receptor sites of post-synaptic neuron. Ligand-gated ion channels of post-synaptic neuron open. Voltage-gated ion channels of post-synaptic neuron open.
Action potential depolarizes pre-synaptic neuron. Vesicles release neurotransmitter molecules. Neurotransmitter molecules diffuse into the synapse. Neurotransmitter molecules bind to receptor sites of post-synaptic neuron. Ligand-gated ion channels of post-synaptic neuron open. Voltage-gated ion channels of post-synaptic neuron open
Describe the characteristics of an action potential, and explain the role membrane permeability changes and ion gates play in the generation of an action potential
Action potential is a rapid, temporary change in membrane potential, allowing neurons to communicate 1-depolarization of membrane from negative to 0, and then briefly positive. 2-repolarization rapidly changes the membrane potential back to negative 3-hyoeroikarization- membrane is slightly more negative than the resting potential. Keeps the charge of Na+ that spreads back upstream from triggering action potential in the wrong direction.
Describe the characteristics of an action potential, and explain the role membrane permeability changes and ion gates play in the generation of an action potential.
Action potential is rapid, temporary change in membrane potential, allowing neurons to communicate. 1. Depolarization of membrane from negative to 0, and then briefly positive. 2. Repolarization - rapidly changes the membrane potential back to negative. 3. Hyperpolarization - membrane is slightly more negative than the resting potential. Keeps the charge of Na⁺ that spreads back upstream from triggering action potential in the wrong direction. When a certain level of depolarization is reached (threshold potential), certain channels in the axon membrane open and allow ions to rush in. The inside becomes less negative and then positive. Action potential depends on voltage-gated channels, which allow different currents result from different volts.
Which of the following statements about action potentials is correct?
Action potentials are propagated down the length of the axon.
Activation of the G alpha q pathway will
Activate phospholiphase C Results in increased concentrations of IP3 and intracellular calcium
CCK
Acts on the gall bladder to cause it to contract and release bile/bile salts
Organic peanut butter can be converted into a "solid" substance at room temperature (to prevent the oil from separating out) by
Adding hydrogens to decrease the number of double bonds between carbon atoms in the molecule
Distinguish between sensory (afferent) nerves and motor (efferent) nerves.
Afferent nerves - transmit sensory info to the CNS Efferent nerves - carries commands from the CNS to the body
Distinguish between sensory (afferent) nerves and motor (efferent) nerves
Afferent nerves- transmit sensory into to the CNS Efferent nerves- carries commands from the CNS to the body
When considering spatial summation of graded potentials, it is important to keep in mind... how far the potential may have traveled. the initial amplitude of the potential. the polarity of the potential. All of the above.
All of the above.
Glial cells: only provide structural and metabolic support. only guide neurons during growth and repair. only help maintain homeostasis of the brain's extracellular fluid. provide structural and metabolic support and help maintain homeostasis of the brain's extracellular fluid. All of the answers are correct.
All of the answers are correct.
Helper T-Cells are important for
All of the below The humoral response Cell-mediated immunity Production of memory cytotoxic T cells Production of memory B cells
Which of the following statements is/are true about steroid hormones?
All of the below They diffuse through the cell membrane They bind to specific receptor proteins They act by turning specific genes on or off
The sphincter of oddi is a muscular sphincter which opens and closes to regulate the secretion of pancreatic enzymes. "Sphincter of Oddi Dysfunction" is a rare disease where the opening and closing of the sphincter no longer properly functions. If the sphincter remains closed even though food is present, digestion of which of the following macromolecules would become more difficult/impossible?
All of the following Protein Starch Fat
Which of the following is not a critical step in clot formation?
All of the following are important steps in clot formation Damage to the endothelial wall of a blood vessel must occur. Exposure to collagen activates platelets, causing them to secrete clotting factors. Calcium and Vitamin K in the plasma act as cofactors in the enzymatic production of thrombin and fibrin. Newly formed fibrin aggregates into threads that trap platelets and red blood cells for clot formation.
The epiglottis
Allows entry of air into the trachea when not swallowing.
Which of the following choices correctly describes the path of carbon dioxide moving out from the interior of the lung?
Alveoli, bronchioles, bronchi, trachea, larynx, pharynx
Which of the following is true regarding epitopes and antigens?
An epitope is the specific region of the antigen that is recognized by an antibody One antigen can have several epitopes
In a relaxed skeletal muscle _____.
the Z lines are farthest apart
The figure below depicts a cell undergoing meiosis. Based on the structure of the chromosomes, one can say that this cell is in
Anaphase I
What is the difference between plant and animal mitosis?
Animal Mitosis: The contractile ring draws the plasma membrane in, forming the cleavage furrow. Cleavage furrow results in 2 daughter cells. Plant Mitosis: A new cell wall forms between the 2 daughter cells. There is no cleavage furrow.
Increasing the concentration of calcium within the cytoplasm of a skeletal muscle will first result in _______________.
Attachment of myosin to actin
Sensors that can detect the carbon dioxide concentration in the blood are located in the
Aorta
Write in: What is the term for programmed cell death?
Apoptosis
Aquaporins are proteins distributed widely throughout bacterial, plant and animal kingdoms. What is the role of aquaporin in the cell membrane? IN what part of the nephron is it especially important? Why is this so?
Aquaporins are proteins in membranes that allow water to pass through the membrane. They are called to open by ADH in the collecting duct & help to retain water. In the descending loop of henle they are very important for water retention
Pepsin and Gastrin
Are both produced by the stomach
Chief cells
Are located in the stomach and secrete pepsinogen
Peptide bonds
Are used to link amino acids
What is located in the Haversian canal and what does the Haversian canal do
Artery, vein, and nerve. Provides bone with a blood supply
Surface area:Volume relationship
As surface area increases, volume increases much faster. Smaller animals must have larger Basal metabolic rates than larger animals. Large animals have low BMRs per cell, therefore, they consume much less energy. If they didn't, the surface area wouldn't be able to keep up with the metabolic demands.
Dr. Baelish wishes to measure the velocity (speed) of blood flow at varius locations within the circulatory system. To do this, he radioactively labels a red blood cell and inserts it into the left ventricle. The location of the radioactive cell is recorded every second, and the velocity of the red blood cell is determined at each location. The data shown below. Which of the following choices best explains the location of the red blood cell at points A and B?
At point A, the RBC is in the Aorta; at point B, it is in a capillary.
In the human immune system, white blood cells produce a chemokine called Interleukin 2 (IL2) in response to infection. Because IL2 can bind to membrane receptors on the surface of the same cell that produced it, this is an example of ______________________ signaling.
Autocrine
Distinguish between the functions of the autonomic nervous system and the somatic nervous system
Autonomic- controls internal processes Somatic- controls voluntary movements
The humoral response involves _______________ and is part of ___________________ immunity.
B cells Acquired
where do B cells and T cells mature?
B cells - Burma T-cells - Thymus
myelomas
B-cell tumors
_____ phase is the period between the completion of DNA replication and the initiation of mitosis a. G1 b. G2 c. S d. G0
B. G2 G1 = the period between the completion of the previous mitosis and the initiation of DNA synthesis for the next mitosis. G2 can = up to 15% of cell cycle in some cells
B cells
BURSA-dependent lymphocytes mature from bone marrow in humans produce antibodies
Distinguish between basal metabolic rate and standard metabolic rate.
Basal metabolic rate - the rate at whcih an animal consumes oxygen while at rest, with an empty stomach under normal conditions. Standard metabolic rate is simply how much energy something consumes
Although structurally similar, different steroid hormones exert their effects by
Binding to different, specific receptors in the cytoplasm
Why is blood considered a connective tissue?
Blood transports materials throughout vertebrate, and has a liquid extracellular matrix called plasmawhich allows it to do this.
When endothermic animals overheat, which of the does not occur?
Blood vessels in the skin contract, drawing blood away from the surface heat.
Ligaments connect ______ to ______While tendons connect _____ to ______.
Bone to Bone Bone to Muscle
Which of the following correctly describes the cellular signaling that could lead to the development of cancer?
Both A & C a. Signals which cause cell division are given too frequently c. Signals which prevent cell division are given too infrequently.
What is similar between endoskeletons and exoskeletons?
Both attach to muscle to transmit muscle forces.
Oxygen is primarily transported through the body and delivered to all tissues
Bound to hemoglobin in red blood cells
List the major components of the central nervous system.
Brain and Spinal Cord
List the major components of the central nervous system
Brain and spinal chord
Bile
Breaks large fat droplets into smaller fat droplets
What signaling system is used in embryonic development where cells in one layer can, upon physical contact with cells in a different layer, bring about differentiation of various tissue types. a. Endocrine b. Exocrine c. Paracrine d. None of the above
C - Paracrine
A resting multipolar neuron is stimulated in the middle of the axon with a threshold stimulus resulting in the generation of an action potential. Which direction will the action potential travel? A. The action potential will travel only toward the axon terminals. B. The action potential will travel only toward the cell body. C. The action potential will travel toward the axon terminals and the cell body. D. An action potential will be observed at the point of stimuli, but will not travel.
C. The action potential will travel toward the axon terminals and the cell body. The configuration of the voltage-gated sodium channel determines which areas of the axon will experience an action potential. Since the neuron is at rest, the activation gate of the voltage-gated sodium channel is closed and the inactivation gate is open all along the axon membrane. A threshold stimulus would cause action potentials to develop at the point of stimulus. Due to the nature of electrotonic conduction, a stimulus in the center of an axon would result in the action potential traveling toward both the neuron's cell body and axon terminals.
cytotoxic T cells (killer T cells)
CD8+ T cells kill cells that are infected with an intracellular pathogen
oligodendrocytes
CNS!!!! specialized accessory cells whose membranes wrap around the axons of certain neurons, increasing the speed of action potential propagation
The lense of the eye is composed of
Crystalline protein
Where is calcium stored in the muscle? What regulates its release? How is it removed from the muscle cell?
Calcium is stored in the sarcoplasmic reticulum. When action potential reaches the T tubule, Calcium channels open and it is free to bind to troponin.
how were neurons initially able to be studied?
Camillo Golgi, in 1873, discovered neurons become visible when preserved nervous tissue is treated w/ a silver nitrate
After ingestion, the first type of macromolecule to be worked on by enzymes in the human digestive system is
Carbohydrate
What is NOT true about amino acids? a. Make up proteins b. Amino group always contains nitrogen c. Carboxyl group is acidic d. Amino acids differ in the properties due to differing R groups e. None of the above. They are all true about amino acids.
Carboxyl group is basic R group is attached to alpha carbon.
Which of the following categories of muscle is/are capable of contracting without signals from the nervous system? That is, which type of muscle has "intrinsic contractility"
Cardiac Muscle
What causes cardiac muscle to contract for relatively long periods of time? How are actin and myosin arranged in smooth muscle?
Cardiac muscle has a prolonged delivery of calcium which allows it to stay contracted longer.
Cell A is a normal cell free from any mutations. Cell B has a mutation in the gene that encodes for p53. As a result, cell B does not make any functional p53 protein. Which of the following would you expect?
Cell B is less likely to halt cell division at the G1/S checkpoint if the DNA has been damaged
Compare the two coordinating systems in animals.
Central Nervous System - Processes information, integrates information from neurons using interneurons to pass signals. Peripheral Nervous System - The Afferent Division transmits sensory info to CNS The Efferent Division carries commands from CNS to the body. Typically, sensory information from receptors in PNS is sent to CNS, where it is processed.
Compare the two coordinating systems in animals
Central Nervous System- Processes information, uses information from neurons using interneurons to pass along signals Peripheral Nervous System- Afferent division transmits sensory info to CNS Efferent division carries commands from CNS to body Sensory information from PNS receptors are sent to the CNS and processed
True or False: What are the two MAJOR subdivisions of the nervous system? a. Autonomic and Somatic b. Autonomic and Peripheral c. Central and Peripheral d. Central and Somatic
Central and Peripheral CNS = brain + spinal cord PNS = neurons that bring info into or out of CNS
In which of the following structures is the kinetochore located on a mitotic chromosome?
Centromere
Describe the role of cholinesterase, and explain what would happen if acetylcholine was not destroyed.
Cholinesterase hydrolizes acetylcholine into acetic acid and choline, allowing a neuron to return to its resting pootential.
Describe the role of cholinesterase, and explain what would happen if acetylcholine was not destroyed
Cholinesterase hydrolyzes acetylcholine into acetic acid and choline, allowing acid a neuron to return to its resting potential
The ____________ control(s) the shape of the lens.
Ciliary body and suspensory ligaments
When a membrane is becoming depolarized, is it getting closer or further to an action potential?
Closer to an action potential. depolarized means it is getting closer to the charge outside the membrane, which means the inside is becoming less negative. resting potential is ~-70mV and once it is depolarized to ~-50mV an action potential will fire
Fill in: _____ are round bacteria and are the smallest, ______ are rod-like, and ______ are spira shape and the largest of the 3 bacteria
Cocci; rods; spirillum
Write in: Why are lipids hydrophobic?
Consist of mostly hydrocarbons which form nonpolar covalent bonds
Antibodies are Y-shaped proteins composed of two regions: a ____________________ region, and a _________________ region so named because its amino acid sequence varies extensively from one B cell to another.
Constant Variable
The renal cortex
Contains the glomeruli of all nephrons
In order for the biceps muscle to properly relax, the triceps muscle must
Contract
Henry is wearing contact lenses. the contact lenses are in direct contact with which of the following structures?
Cornea
Which of the following lists the proper path of light through the eye?
Cornea, aqueous humor, pupil, lens, vitreous humor, retina, optic nerve
Epithelial: cuboidal, columnar, squamous
Cuboidal - may exist in single or multiple layers, protect organs and filter substances Columnar - can be innervated, so can serve as a sensory function. found in ears and eye. squamos - thin construct allows transmembrane movement, serves as filters.
A macrophage has just consumed a harmful pathogen. Which of the following organelle(s) is/are necessary to digest this pathogen and present antigen fragments on the macrophage surface via MHC II molecules?
Cytoskeleton Lysosome
Which of the following is not an example of innate immunity?
Cytotoxic T-Cells destroying a pathogen-infected somatic cell.
Which of the following ion flows would result in an EPSP? A. Na+ into the cell B. K+ out of the cell C. Cl- into the cell A & C
Na+ into the cell
Cancer cells use which signaling system to survive treatments that inhibit their access to the growth factors they require for growth and division a. Endocrine b. Exocrine c. Paracrine d. None of the above
D - none of the above. They use the AUTOCRINE signaling system.
zinc finger
DNA-binding proteins that activate when steroids attach to them, which then enter the nucleus and bind to DNA, inducing transcription
During which part of the heartbeat do the chambers of the heart FILL with blood?
Diastole
The sliding filament model
Describes the process by which thick and thin filaments of skeletal muscle overlap to cause contraction
A heptocyte (liver cell) has been infected by a virus. The hepatocyte will
Display viral antigens on its MHC I molecules to cytotoxic T-cells
A water molecule is currently in the ascending loop of Henle. Assuming that the water molecule is not reabsorbed, what is the very next structure within the nephron it will encounter?
Distal convoluted tubule.
Diagram or describe the three major patterns of neural circuits.
Divergence - output from one neuron to many Convergence - output from many neurons to one Feedback - output from the postsynaptic neuron goes to a presynaptic neuron that already provided input to it.
Diagram or describe the three major patterns of neural circuits
Divergence- output from one neuron to many -Convergence- output from many neurons to one Feedback- output from the postsynaptic neuron goes to a presynaptic neuron that already provided input to it
CD4 receptors
Dock to MHC II molecules
What are "Emergent Properties? Give an example from the plant or animal world.
Emergent properties are properties that rely on a symbiotic relationship. Chlorophyll cells with all other cells surrounding them in a petri dish will not perform photosynthesis. If the connections to the required cells have been severed. Another example is brain neurons piled in a petri dish without the neural connective tissue will not have consciousness due to the lack of required connective tissue
List two classes of neuropeptides, and explain how they illustrate overlap between endocrine and nervous control
Endorphins and Enkephalins -located at sensory pathways -excite, inhibit, or modulate
List two classes of neuropeptides, and explain how they illustrate overlap between endocrine and nervous control.
Endorphins and Enkephalins - located at sensory pathways - excite, inhibit, or modulate
What is the following statement; "Endothermy and ectothermy are best understood as contrasting adaptive strategies" attempting to illustrate conceptually?
Endothermy can remain active in winter and at night because they produce their own heat, but the energy in this heat is lost and cannot be used for other processes such as reproduction. They also need a lot of energy-rich food Ectotherms can thrive on lower amounts of food and can use a greater portion to support reproduction.
How does the structure of each of the following tissues relate to its function? A. Epithelial tissue
Epithelial cells cover the outside of the body, the surfaces of organs, and forms glands. Often joined by tight junctions and desmosomes. Apical side, which face away from other tissues and toward the environment. Basolateral side faces the interior and connects to connective tissues, made by fibers called the basal lamina
Define equilibrium potential, and explain why the K+ equilibrium potential is more negative than the resting potential
Equilibrium potential is the voltage at which there is no net movement of K+ -K+ ions travel out of the cell through K+ leak channels, making the inside more negative. This buildup counteracts the gradient that moves the K+ out.
Write in: What hormones are responsible for differences in hair pattern, subcutaneous fat distribution, bone growth, and Adam's apple development.
Estrogen + Testosterone responsible for all the secondary male and female sex characteristics that first appear in puberty
EPSP
Excitatory postsynaptic potentials -changes in postsynaptic cell that brings the membrane potential closer to threshold
What are the principle types of skeletons in larger animals? Which type do humans have? What are the purposes of a skeleton?
Exoskeletons - hard, hollow structures that envelope the body. Hydrostatic skeletons - use pressure of internal body fluids to support the body. Endoskeletons - hard structures inside the body.
True or False: Gastrin and CCK use the paracrine signaling system to create a change in body.
FALSE - Endocrine (secreted into blood, travels through blood, hits receptors)
True or False: Increase in light level activates more retinal neurons, resulting in greater peak value of individual action potentials
FALSE - results in increased action potential frequency.
True or False: Lipid-soluble proteins (like steroids) can effect any cell because they are able to pass through the phospholipid bilayer
FALSE - the cell still needs the receptor. Otherwise the lipid-soluble protein will just pass through the cell without stimulating a change.
True or False: There is no limit on the maximum frequency at which action potentials can be generated.
FALSE - there is a refractory period that sets a limit on max frequency at which action potential can be generated.
True or False. Intercalated disks are structures that connect smooth muscle cells and relay the electrical signals that cause peristalsis.
False
True or False: To ensure that the atria empty completely before the ventricles contract, cells in the SA node form a relay point where electrical impulses are delayed for ~0.1 second before they are conducted toward the Purkinje fibers and the apex of the heart.
False
True or False: the resolution of standard light microscopy is high enough to study organelles
False
True or False: A hormone binds to a G protein which then activates a G protein-coupled receptor
False - A hormone (charged, hydrophilic) will bind to a G protein-coupled receptor which causes the receptor to undergo a conformational change which then allows it to activate a G protein located on the inner side of the plasma membrane.
True or False: Graded potentials are signals that carry information along axons
False - Action potentials are signals that carry info along axons
True or False: Less than 30% of the cerebral cortex, in dozens of integrating centers, is active in creating visual perceptions
False - At least 30%
True or False: At resting potential, a neuron contains no open K+ channels and many open Na+ channels + Na+ ions can diffuse out of the cell
False - Contains many open K+ channels and fewer open Na+ channels K+ can diffuse out of the cell
True or False: A Neuron can produce only about 1 action potential per second
False - They can produce hundreds of action potentials per second.
True or False: Lipid-soluble hormones diffuse across membranes and then travel freely in bloodstream.
False - They do diffuse across membranes, but then travel in blood stream bound to transport proteins. Then diffuse through membrane of target cells (cells with receptors in cytoplasm)
True or False: Unsaturated fatty acids do not have double bonds
False - Unsaturated fatty acids have one or more double bonds.
True or False: Enzymes are changed by the reactions
False - although the ultimately wear out and must be turned over and replaced in the cytoplasm
True or False: Cardiac muscles cannot generate action potentials without neural input
False - cardiac muscles CAN generate Ax Potentials without neural input.
True or False: The blind spot (Optic Disk) contains photoreceptor portions of rods and cones.
False - does not contain photoreceptor portions of rod and cones. It contains their AXONS.
True or False: All cholesterol in the body is harmful to our health
False - essential, a key component in animal cell membrane. High levels may contribute to cardiovascular disease
True or False: Phospholipids polymerize into fatty acids
False - fatty acids polymerize into lipids and phospholipids
True or False: The Endoplasmic Reticulum is found in animal eukaryotic cells but not plant eukaryotic cells
False - found in all eukaryotic cells
True or False: Hormones are active once they enter the blood
False - inert in blood.
True or False: Information is transmitted through neurons as an electrical current based on the movement of sodium and potassium ions only
False - it is based on the movement of charged ions (mainly Na+ and K+, but not only those ions)
True or False: Steroid hormones require a second messenger to exert their effects
False - protein/peptide hormones require a second messenger
True or False: The lateral geniculate nuclei relay information to the primary visual cortex in the cerebellum
False - relay information to the primary visual cortex in cerebrum (See figure 50.20 in ppt (or book))
True or False: The translation (reading the messenger RNA on ribosomes to synthesize proteins) takes place in the nucleus
False - takes place in the cytoplasm
True or False: Polypeptides are polymers built from hundreds of types of amino acids
False - they are built from the same set of 20 amino acids
True or False: Water-soluble hormones are secreted by diffusing across the membrane.
False - they are secreted by exocytosis (because hydrophilic, they need help cross membrane). Once out, they are free in blood stream until they bind to cell-surface receptors.
True or False: Leaky K+ channels use ATP to always allow K+ out of cell
False - this is a passive process. K+ wants to move outside cell because it is more concentrated in cell (salty banana)
True or False: The speed of an action potential decreases with the axon's diameter
False- Speed of action potential INCREASES with the axon's diameter
True or False: The stimulus leading to contraction of a muscle fiber is an action potential in an interneuron that makes a synapse with the muscle fiber
False: Ax Potential in a motor neuron that makes a synapse with the muscle fiber
True or False upon stimulation of muscle contraction, calcium from the motor neuron is released, binds to troponin, and this causes in tropomyosin to "unblock" the myosin-binding site on actin filaments.
False: Calcium is released from sarcoplasmic reticulum
True or False: In DNA, the sugar is ribose and in RNA the sugar is deoxyribose
False: DNA sugar = deoxyribose; RNA sugar = ribose
True or False: Membranes provide increased volume for gas & nutrient exchange, waste removal, and specific enzyme-mediated metabolic functions
False: membranes provide increased surface area!
True or False: In the sliding filament model, the "head" of a myosin molecule binds to an actin filament and pulls the thin filament towards the outer Z line of the sarcomere
False: pulls the thin filament towards the center of the sarcomere (M line).
True or False. Although actin and myosin are found in all eukaryotic cells, they are organized into stable thick and thin filaments ONLY in skeletal muscle.
False; as discussed in class, cardiac muscle contains stable thick & thin filaments (like skeletal muscle) but remains single-celled (like smooth muscle).
When we consider its function, it becomes clear why a person must be especially careful to restrict intake of __________ after surgical removal of the gall bladder.
Fat
Because they can accumulate to high levels in the body, excess amounts of which of the following can have toxic effects?
Fat-soluble vitamins
Lacunae What is it? What does it contain?
Fluid filled spaces Contais osteocytes (osteoblasts and osteoclasts) - build and break down bone.
Which is/are the most common inhibitory neurotransmitter(s) of the CNS? GABA only glycine only glutamate only GABA and glycine All of the answers are correct.
GABA and glycine
In its inactive form, the alpha subunit of a G protein is bound to
GDP
Place these events in proper order:
GPCR-Hormone binding causes replacement of GDP by GTP on the G alpha subunit of the G protein Conformational change in G alpha causes decreased affinity for G beta y Dissociation of G alpha from G beta y G alpha s subunit attached to GTP activates adenylyl cyclase Production of cAMP cAMP activates Protein Kinase A (PKA)
Which of the following is not true about GPCR signal transduction?
GPCR-signal transduction is specific for the adenylyl cyclase/cAMP/PKA pathway, and therefore does not activate pathways that alter intracellular calcium concentrations.
Describe the three major functions of the nervous system.
Gather information, process it, and initiate a response
Describe the three major functions of the nervous system
Gather information, process it, initiate a response
Fill in: The amino acid sequence of a polypeptide is is programmed by a _______
Gene genes are made of DNA
Briefly describe how Ghrelin and Leptin work together to control appetite. in your answer, for each hormone, tell me where it is made, its effect on appetite, and where in the brain it binds to specific receptors to alter behavior.
Ghrelin is produced by the stomach & alerts the hypothalamus to the fact the stomach has been empty for too long. Leptin counteracts Ghrelin & causes a sated feeling. It is produced in the white fat cells & sends signals to the hypothalamus. Ghrelin causes hunger. Leptin stops hunger.
Non-neural cells called ______________ provide nutrients and help maintain homeostasis for neurons in the CNS and PNS.
Glia
Which of the following is true about glucagon and its effects in the body
Glucagon is secreted from the pancreas and increases the blood glucose concentration
Write in: When Glucagon is released into blood what happens? Which results in what in BGL?
Glucagon stimulates liver to break down glycogen and release glucose. This causes BGL to rise
Distinguish between white matter and gray matter
Gray matter has cell bodies, dendrites, axon terminals, and is the site of all synapses White matter has axons that connect gray matter
Distinguish between white matter and gray matter.
Gray matter has cell bodies, dendrites, axons terminals, and is the site of all synapses. White matter has axons that connect gray matter.
Why is HIV infection, if left untreated, so devastating to the overall function of the immune system? Be specific - which cell is destroyed by HIV infection, and what is the result of its absence?
HIV infects the helper T-cells stopping them from performing their normal functions. The helper T-cells no longer attach to the microphage & send alerts to B-cells and Cytotoxic T-cells. They are transformed into HIV producing cells. The basic response system of the active immune system is crippled.
At the conclusion of meiosis I, each daughter cell is considered
Haploid, and the chromosomes are each composed of two chromatids.
How would an abnormally large oval window in a mouse affect that animal's hearing?
Hearing ability would be reduced in comparison with normal mice
How are other organisms able to see in wavelengths that humans cannot?
How are other organisms able to see in wavelengths that humans cannot? Opsins are responsible for color detection.
cell body
integrates incoming signals and generates outgoing electrical signal to axon
in 1944, three scientists (MacLeod, Avery & McCarty) and their co-workers proved that DNA, not protein, is the genetic material. They did this by breaking open bacterial cells, isolating the fractions containing protein, DNA, RNA, Carbohydrates and lipids, and testing each fraction. They showed that only DNA could transform bacteria from a non-lethal to a lethal strain capable of causing pneumonia. This illustrates
Hypothesis testing Reductive Science
In Figure 1 above, two cell cycles of a somatic cell are shown. Which number represents S phase?
II
Describe the major differences between single-loop and double loop circulatory systems.
IN a single loop circulatory system the heart pumps only deoxygenated blood. This blood goes to the respritory system (normally gills) and then goes through the body dispersing oxygen before returning to the heart. In a double loop system, deoxygenated blood is pumped to the lungs and then returns to the heart where it is pumped to the rest of the body. This helps get the blood to all of our tissues and fights gravity.
13. In Figure 1 above, which number represents mitosis?
IV
Why is memory thought to involve changes in particular synapses?
In some systems, an increased release of neurotransmitters occurs after learning takes place.
Which of the following offers the best example of passive immunity?
In the 9th month of fetal life, a fetus receives antibody directly from her mother.
The primary reason all animals need a continuous supply of oxygen is that
In the absence of oxygen animals cannot derive the maximum amount of ATP from food.
Administration of tetrodotoxin (TTX) will
Inactivate voltage gated sodium channels
A patient is hospitalized with muscle spasms caused by failure of back muscles to relax after contraction. Which of the following would be most likely to help?
Induce tropomycin and troponin to bind to the myosin binding sites on actin.
Which of the following would most likely increase neurotransmitter release at a typical nerve synapse? Decreased extracellular [Ca2+] conotoxin that blocks voltage-gated Ca2+ channels Inhibition of the Ca2+-ATPase pump Application of a Ca2+/calmodulin-dependent protein kinase (CaM-kinase) inhibitor
Inhibition of the Ca2+-ATPase pump
Point of attachment of muscle to the one is called
Insertion
You radioactively label a molecule of estradiol and administer it to a petri dish of ovarian cells growing in tissue culture. You wait 30 minutes after administration the test the dish to determine the location of the radioactive estradiol. because Estradiol is a steriod hormone, you would expect most of it to be found
Inside the cells, in the cytoplasm Inside the cells, in the nucleus
Fill in: Cardiac muscles consist of striated cells electrically connected by _______
Intercalated disks
A hypothesis
Is a Prediction Can become a theory if the data never disprove it.
Which of the following statements about pepsin is true? Pepsin:
Is formed from its inactive precursor molecule, pepsinogen, in the acidic environment of the stomach
Gastrin
Is secreted from the stomach and stimulates digestion in the stomach
What fills the spaces between cells in all animals more complex (with more tissue layers) than a hydra?
Interstitial fluid
Fill in: _____ are like bridges and do not undergo a significant change when letting in proteins vs. ______ are like ferry boats where they undergo a conformation change to let proteins into the cell
Ion Channels vs. Carrier Transport Proteins
Why would the breast meat of a pigeon consist of dark meat?
It is composed of slow muscle fibers.
A newly discovered chemical messenger is applied to a rat testis. It is determined that this messenger activates a G-protein coupled receptor (GPCR) and increases the amount of cAMP within rat testis. Which of the following statements is true about this newly discovered chemical?
It is likely to be a protein that is binding to a receptor on the plasma membrane and activating a G Alpha S pathway.
The epothilones are a potentially new class of drugs for the treatment of cancer. A drawing of a molecule in the epothilone class is shown below. Administration of these drugs will allow cells to enter mitosis and progress to metaphase. However, the cells will be incapable of entering anaphase and completing mitosis. Which of the following answer choices is the best explanation of epothilone's mechanism of action?
It prevents shortening of microtubules
What might occur to an animal with an untreated lesion on its brain stem?
It would likely die. As the brainstem is responsible for most of the core bodily functions, the animal would not survive.
The tertiary structure of a protein refers to
Its 3-D conformation
Define equilibrium potential, and explain why the K+ equilibrium potential is more negative than the resting potential.
K⁺ ions travel out of the cell through K⁺ leak channels, making the inside more and more negative. This buildup counteracts the gradient that moves the K⁺ out. Equilibrium potential is the voltage at which there is no net movement of K⁺.
How does body size affect animal physiology?
Large animals need more food, produce more waste, take longer to mature. Small animals are more susceptible to damage from cold and dehydration than large animals, because they lose heat and water faster.
Lamellae
Layers of membrane
At point a
Leaky potassium channels are open Voltage gated potassium channels are closed
Canaliculi What do they look like What do they do?
Little indents in heavily mineralized collage containing bones. Allows communication between blood supply and osteocytes.
Botox blocks synaptosomal-associated protein 25 (SNAP-25), a protein that promotes synaptic vesicle fusion. The mechanism by which Botox can temporarily reduce the formation of wrinkles in the face is most directly due to which of the following? Locally blocking the release of synaptic transmitter from motor neurons Preventing the opening of sodium channels on muscle membranes Decreasing the amount of calcium released from the sarcoplasmic reticulum Enhancing the enzymatic hydrolysis of acetylcholine at the neuromuscular junction
Locally blocking the release of synaptic transmitter from motor neurons
B. Connective tissue: loose connective tissue (adipose), cartilage, bone
Loose connective tissue - contains array of proteins in soft matrix; serves as a packing material between organs or padding under the skin. Adipose is this type made of cells that are dominated by fat droplets and a loose matrix of fibers and fluid. Soft matrix makes it good for this. Dense connective tissue - found in tendons and ligaments that connect muscles, bones, and organs. The matrix has tough collagen fibers. Supporting connective tissue: Cartilage and bone are connective tissues that provide structural support and protection for organs. Has a very firm extracellular matrix.
Macular degeration is a condition of the eye characterized by a loss of cone photoreceptors. which of the following describes the most likely changes in vision of a patient diagnosed with macular degeneration?
Loss of vision in the center of the field of view.`
How does the ear allow humans to distinguish the volume of different sounds?
Louder sounds induce a higher frequency of action potentials than do softer sounds
A patient has heartburn caused by leakage of acid from the stomach up into the esophagus. Which sphincter is not functioning normally in this patient?
Lower esophageal (Cardiac) sphincter
The cells of a mouse are much more metabolically active than those of a frog, and therefore require greater energy (ATP) production. Which of the following would you expect to have a larger surface area in the mouse than in the frog?
Lungs, Small intestine, Circulatory system, (ALL OF THE CHOICES ARE CORRECT)
Homeostasis
Maintains certain biological conditions, such as blood pH and CO2 concentration, within a narrow range.
Which cell-and-signal molecule pair is responsible for initiating an inflammatory response?
Mast cells and histamine
Write in: Membrane proteins have hydrophilic regions protruding from either side of the phospholipid bilayer and are dispersed throughout the membrane. This does what?
Maximizes contact of hydrophilic regions of proteins and phospholipids with water in the cytoplasm and extracellular region.
Which of the following is false?
Meiosis in spermatogenesis produces two haploid sperm from one primary spermatocyte.
Which of the following is critical to the function of most exoskeletons, endoskeletons, and hydrostatic skeletons?
Muscles interact with the skeleton in antagonistic groups.
In what stage does synthesis of new genetic material occur?
Mitosis, Interphase
Structure in living things is organized at levels increasing complexity. to which of the following best illustrates the hierarchy of complexity.
Molecule, Cell, Tissue, Organ, Organ System, Organism
Fill in: Motor output leaves the brain or ganglia via _____, which triggers muscle activity
Motor neurons
What is the structure of a skeletal muscle? You should know the relationship between a muscle fiber, a myofibril, and a sarcomere. The following parts of the sarcomere are also important: Z line, A band, I band, H zone. Know the relationship between each of these parts of the sarcomere and the locations of actin and myosin in the sarcomere.
Muscle fiber - a long thin muscle cell Myofibrils - threadlike, contractile filaments inside muscle fibers. Sarcomeres - alternating light/dark units which repeat along the myofibril. Thick (myosin) and thin (actin) filaments overlap in the dark sections. Z Line - the ends to which a thin filament attaches. A Band - Middle area where thick and thin filaments can be found I Band - contains thin filaments but no thick filaments H Zone - Area of only thick filaments Sarcomeres shorten as myofibrils contract. Sarcomeres lengthen when the cell relaxes.
What is the structure of a skeletal muscle?What is the relationship between a muscle fiber, a myofibril, and a sarcomere?
Muscle fiber- a long thin muscle cell Myofibrils- threadlike, contractile filaments inside muscle fibers Sarcomeres- alternating light/dark units which repeat along the myofibril. Thick (myosin) and thin (actin) filaments overlap in the dark sections Z line- the ends to which a thin filament attaches A band- middle area where thick and thin filaments can be found I band- contains thin filaments but no thick filaments H zone- area of only thick filaments Sarcomeres shorten as myofibrils contract. Sarcomeres lengthen when the cell relaxes
Fill in: Each muscle fiber is itself a bundle of smaller _____ arranged longitudinally
Myofibrils
What happens if the muscle runs out of ATP
Myosin forms permanent cross bridges-rigor mortis
What is ATP used for?Which of the protein molecules (actin or myosin) actually bends to cause contraction?Do the myofilaments themselves contracts?
Myosin is bent when ATP is attached, Myosin straightens and attaches to actin when it is hydrolyzed to ADP and P. When P releases, Myosin bends, pulling the actin closer. ATP binds, and it releases the acton. When ATP is absent, the muscles can't release the actin and stiffen
Which of the following statements is true?
NONE OF THE FOLLOWING Leptin is made in adipose and causes hunger Leptin is made in the stomach and causes satiety (a feeling of fullness) Ghrelin is made in adipose and causes hunger Ghrelin is made in the stomach and causes satiety (a feeling of fullness)
Which of the following structures is incorrectly paired with its function?
NONE OF THE FOLLOWING Stomach- production of HCL and pepsinogen to initiate protein function? Oral Cavity- initiation of starch digestion by amylase Gall Bladder - bile storage Pancrease- production and secretion of lipase for fat digestion
The rising phase of the action potential is due to: Na+ flow into the cell only. Na+ flow out of the cell only. K+ flow out of the cell only. K+ flow into the cell only. Na+ flow out of the cell and K+ flow into the cell.
Na+ flow into the cell only.
The two solutes that contribute most to the osmotic balance of our body fluids
NaCl and urea
The _______________ is the functional unit of the kidney.
Nehpron
Fill in: Neurons leave the processing centers called _______
Nerves
What regulates calcium release in muscles
Nervous stimulation causes a depolarization of the muscle membrane (sarcolemma) which triggers the release of calcium ions from the sarcoplasmic reticulum
Define neuromodulator, and describe how it may affect nerve transmission.
Neuromodulator - a substance other than a neurotransmitter that is released by a neuron and transmits info to other neurons.Ch
Write in: A pre-synaptic cell (neuron) transmits information to a postsynaptic cell. What can a postsynaptic cell be (list all possibilities)
Neuron, muscle, gland cell
D. Nervous
Neurons have projections that contact other cells. Dendrites are the highly branched, short processes that contact other cells and transmit electrical signals from them to the cell body. Axons are long structures that carries electrical signals from the cell body to other cells.
When an action potential reaches the end of an axon, ____________________ is/are released into the synapse.
Neurotransmitters
A patient has a mutation in the gene for secretin, which causes him to produce an inactive form of this hormone. Without active secretin, the patient will be unable to
Neutralize stomach acid that enters the small intestine
Next to each of the following, indicate which cell group(s) match the term or phrase. Use: P for prokaryotes only; E for eukaryotes only; B for both; N for neither. ________ Single circular chromosome ________ Fluid-mosaic cell membrane ________ Membrane-bound nucleus ________ Peptidoglycan in cell wall ________ Ribosomes ________ Mitosis ________ Meiosis ________ Plasmids ________ Flagellum ________ Chloroplasts
Next to each of the following, indicate which cell group(s) match the term or phrase. Use: P for prokaryotes only; E for eukaryotes only; B for both; N for neither. ________ Single circular chromosome P ________ Fluid-mosaic cell membrane B ________ Membrane-bound nucleus E ________ Peptidoglycan in cell wall P ________ Ribosomes B ________ Mitosis E or B ________ Meiosis E ________ Plasmids P ________ Flagellum B ________ Chloroplasts E
What happens if twice as many inhibitory postsynaptic potentials (IPSPs) as excitatory postsynaptic potentials (EPSPs) arrive at a postsynaptic neuron in close proximity?
No action potential results
Write in: Can Na+ channel be re-activated without any "rest" period?
No, there is a refractory period after an action potential where a second action potential cannot be activated. This refractory period is a result of temporary inactivation of the Na+ channels (also makes sure action potential goes in one direction dow axon)
Which of the following comparisons of rods and cones is false?
Nocturnal animals have fewer rods than diurnal animals.
In the fetus, the foramen ovale
None of the above
Malaria is a disease where red blood cells are infected by a parasite. As a result of this infection, one would expect to find parasitic antigens displayed on the red blood cell's
None of the below MHC class 1 molecules MHC class II molecules CD4 receptors CD8 receptors
The bicuspid valve
None of the following Is located on the right side of the heart Allows or prevents the flow of deoxygenated blood Is closed during atrial systole Is open during ventricular systole
Which of the following is NOT an endocrine gland?
None of the following Pancreas Thyroid gland Ovary Adrenal gland
During S phase, the chromatin of a chromosome is ____________ and chromosomes are _________ using a microscope
Not tightly packed...not visible
Area of bone where a muscle is firmly attached
Origin
How are osteocytes able to attain oxygen and nutrients?
Osteocytes obtain their necessary nutrients and gaseous exchange from blood vessels that are threaded though channels in the extracellular matrix. The channels are called Haversian canals. These larger Haversian canals communicate with small canaliculi-- microscopic channels which in turn communicate with the osteocytes themselves.
Voltage-gated ion channels Neurons and muscle cells are "excitable", which means they can generate action potentials, which are large, transient changes in their membrane potential. The action potential (AP) has four basic phases: (1) the rising phase, (2) the falling phase, the undershoot (3), and the return to the baseline resting membrane potential (4). The action potential is the result of changes in the permeability of voltage-gated ion channels. Unlike leak channels, voltage-gated channels respond to changes in the transmembrane electrical field. There are voltage-gated channels for Na+, K+, and other ions. Almost all types of voltage-gated channel open in response to a movement of the membrane potential in the positive direction (depolarization). Next you will explore the permeability changes that must occur to bring the membrane potential from the peak of an action potential all the way to the undershoot, which is below the resting membrane potential. Set "Ion/Permeabilty presets" to Generic Cell to simulate a relatively standard neuron. Set the Na+ permeability to 450. The membrane potential will now be +32.0 mV. This is approximately the condition of a typical neuron at the end of the rising phase of the action potential. Note that the relative permeability for K+ is 100. From this staring point, what must happened to PK and PNa to bring the membrane potential to -70 mV? Assume that PK cannot go above 9999 and the PNa cannnot go below 5 (because the Na+ leak channels are always open). PK must increase and PNa must decrease. PK must increase and PNa must increase. PK must decrease and PNa must increase. PK must decrease and PNa must decrease.
PK must increase and PNa must decrease. The rising phase of an action potential requires a large increase in the permeability of the plasma membrane to Na+. However, an action potential is a brief event. In order to bring the membrane potential down during the falling phase, the permeability of the plasma membrane to K+ must increase by a large amount. As PK rises, PNa falls due to a process called inactivation, which closes voltage-gated Na+ channels. The combination of a rise in PK and a decrease in PNa allows the membrane potential to go below the resting membrane potential. This phenomenon is called the under shoot. Eventually, most of the voltage-gated channels close and the membrane potential is primarily determined by the leak channels.
sharks?
PLATYPUS LOCATES ITS PREY IN A MUDDY RIVER
Schwann cells
PNS!!!! specialized accessory cells whose membranes wrap around the axons of certain neurons, increasing the speed of action potential propagation
Schwann cells
PNS, the specialized accessory cells that support neurons... called glia... form myelin sheath
Timmy just ate a cheeseburger. The carbohydrates in the cheeseburger are being digested and released into the bloodstream as glucose. As a response to this increase in blood glucose, the ____________ will release ______________.
Pancrease Insulin
A cell releases a protein which signals other nearby cells to increase their rate of cell division. The protein that was released by the first cell is an example of a/an ______________________ messenger.
Paracrine
Fill in: What breaks down peroxide made in cells?
Peroxisome (loaded with catalase)
Kinases are enzymes that will add ________________ groups to other molecules.
Phosphate
The major type of lipid found in all cell membranes is
Phospholipid
The cytoplasm of adjacent plant cells is connected via tiny communicating channels called _________________ which are found in the intervening cell walls; therefore, in plants, the cytoplasm is, in principle, continuous from one cell to the next.
Plasmodesmata
In a in vitro experiment on a nerve cell, the Vm is artificially hyperpolarized to -115 mV. An inhibitory neurotransmitter is then applied, and it causes a partial depolarization of the membrane. Which of the following cation channels was most likely activated? Calcium channels Potassium channels Sodium channels Sodium-potassium channels
Potassium channels
Blood flow through the capillaries is controlled by
Pre-capillary sphincters Pressure in the arterioles
A drug that blocks CD4 receptors would
Prevent the activation of B cells Prevent the activation of helper T-cells
Groups of organisms classified as Archaea are also known as "extremophiles" and are comprised of
Prokaryotes
Where does Recombination and Crossing Over take place?
Prophase 1 of Meiosis 1
What is the relationship between the size of brain area devoted to a body part and that body part?
Proportionate to the sensitivity of the body part
Fill in: 1 or more polypeptides make up a _______
Protein
Which enzyme classes dephsphorylate a protein, turning it off.
Protein Phosphoratases
which of the following substances involved in digestion is/are initially released as inactive precursors called zymogens?
Protein-digesting enzymes
Write in: Which type of hormone often leads to activation of membrane bound G proteins?
Protein/Peptide (hydrophilic, charged)
Which of the following contains ONLY polymers?
Proteins, lipids, polysaccharides
Negative pressure breathing involves ___________________ while positive pressure breathing involves ________________.
Pulling air into the trachea Pushing air into the trachea.
Back flow of deoxygenated blood into the right ventricle is prevented by the ________________________________ valve; backflow of oxygenated blood into the left ventricle is prevented by the ___________________________ valve.
Pulmonary Semilunar Valve Aortic Semilunar Valve
Which of these carries the most highly oxygenated blood?
Pulmonary Veins
Choose the correct sequence of events in hormone signaling.
Receptor binding -> Signal transduction -> receptor binding
You are performing an experiment on the axon of a neuron. You give the axon two threshold stimuli less than 0.002 seconds apart. However, you only see one action potential occur on your monitor. You decide to try the experiment again using the same voltage on the first stimulus, but a suprathreshold stimulus for the second stimulus. The two stimuli are again given 0.002 seconds apart. This time you see two action potentials. Which of the following concepts best explains why you saw only one action potential during the first experiment, but observed two action potentials during the second experiment? All or none law Absolute refractory period Membrane potential Relative refractory period
Relative refractory period The first experiment in which no action potential is observed during the second stimulation indicates the second stimulus is occurring during a refractory period. The question is during which refractory period does the second stimulus occur? The second experiment answers this question. Since the second stimulus (suprathreshold stimulus) generates the second action potential, this indicates that the second stimulus occurs during the relative refractory period.
Explain what a resting potential is, and list four factors that contribute to the maintenance of the resting potential
Resting potential is the difference in charge across a neurons membrane when it is not communicating with other cells 1-a different concentration of ions allows the gradient to exist, the phospholipid bilayer prevents ions from crossing 2-Ion channel- a protein in the pore that selectively allows ions to pass through 3-Ions can be carried across vi cotransporter proteins, with another ion that diffuses along its gradient 4-pumped against an electrochemical gradient by a membrane protein that hydrolyzes ATP
Clonal selection is a process that _________________________ to fight an infection.
Results in a population of B and T cells with receptors for a specific antigen
Fill in: The functional unit of a muscle is called a _______
Sarcomere
temperature homeostasis in endotherms
Sensors in the skin sense heating or cooling, and respond by altering electrical signals. Electrical signals are transmitted to an integrator in the hypothalamus Cells in the hypothalamus send signals to effectors to return body temperature to the set point via the appropriate response: sweating, panting, shivering, or fluffing feathers.
During kidney dialysis, the addition of which of the following molecules to the dialysate should be unnecessary? (remember - the dialysate is the fluid against which the patient's blood is dialyzed)
Serum proteins
Contraction of which of the following muscle types is under voluntary (intentional) control?
Skeletal Muscle
How do the functions of the body as a whole (breathing, eating, elimination of wastes, etc.) relate to the processes that occur in single cells?
Skeletal muscle surrounds the digestive and urinary tracts and controls swallowing, defecation, and urination.
C. Muscle: skeletal, cardiac, smooth
Skeletal muscles attach to bones and exerts force on them, controlling movements. Also controls swallowing, defecation, and urination. Cardiac muscle - makes up walls of heart and pumps the blood throughout the body Smooth muscle - tapered at each end, form a muscle tissue that lines the walls of the digestive tract and blood vessels.
At rest, there is a higher concentration of ________________________ outside the membrane that inside the membrane of the neuron.
Sodium Ions Positive charge
Diabetes mellitus is a disease characterized by the destruction of the B-cells of the pancrease. which of the following would you expect to find in a patient with diabetes mellitus? Assume that the patient is not receiving any medication to help manage their condition.
Somatic cells would be unable to take up glucose from the blood stream An increase in insulin production in the Aplha-cells of the pancreas
Distinguish between the functions of the autonomic nervous system and the somatic nervous system.
Somatic nervous system - controls voluntary movements Autonomic nervous system - controls internal processes
If a sprinter began an endurance running program, which of the following would occur?
Some fibers would develop a higher mitochondrial density
Mammals have a family of 500 and 1000 genes that encode receptor proteins on the surface of odor-receptor neurons. If all mammals have these genes, why do some mammals have a better sense of smell than others do?
Some of the genes may have been mutated and rendered inactive in some species but not in others.
Define reflex and describe the pathway of a simple spinal reflex.
Spinal reflex - sensory neurons stimulate interneurons in the spinal cord that directly stimulate motor neurons
What happens when BGL rise after eating? (name everything that leads to BGL declining)
Stimulus = rise in BGL 1. Beta cells in pancreas release insulin into the blood 2. Insulin signals for body cells to take up more glucose (from the blood) and/or signals liver to take up glucose and store it as glycogen. 3. BGL decline because glucose is removed from blood and enters cells or liver.
Two students studying physiology taste a known "bitter" substance, and both report sensing bitterness. They then sample another substance. Student A reports sensing both a bitter taste and a salty taste, but student B reports only a salty taste. What is the most logical explanation?
Student A has a protein receptor capable of detecting a bitter molecule found in that substance, whereas student B lacks that particular protein receptor.
Fill in: Path of light: Sun > __1__ > __2__ > __3__ > __4__ > __5__ > __6__ > __7__ > Optic Nerve
Sun 1. Cornea 2. Aqueous Humor 3. Pupil 4. Lens 5. Vitreous Humor 6. Retina 7. Blind Spot Optic Nerve
An infant is born 18 weeks before the expected delivery date. The infant is having a difficult time inhaling because his lungs are missing
Surfactant
What would occur if the uptake of calcium ions was blocked in the sarcoplasmic reticulum?
Sustained muscle contraction
what is the hormone that triggers many of the changes observed in metamorphosis?
T3 - triiodothyronine
T cells
THYMUS-dependent lymphocytes involved in graft rejection along with other immune functions, including recognizing and killing host cells that are infected with a virus
True or False: Ion channels that establish membrane potential (aka voltage-gated and ligand-gated) have selective permeability
TRUE
When do nuclear membranes reform and chromosomes at opposite ends of the dividing cell start to decondense? a. Anaphase b. Telophase c. Cytokinesis d. G1 e. G0
Telophase
In a primary oocyte, the duplicated chromosomes have condensed and become visible, the nuclear membrane has disappeared and the spindle has formed. In the next step, the _____________ line up in the middle of the cell as division occurs by ____________.
Tetrads.....meiosis
Describe the function and location of each type of supporting cell.
The Na⁺/K⁺-ATPase pumps Na⁺ out and K⁺ in, located in the cell membrane. K⁺ ions travel out of the cell through K⁺ leak channels in the cell membrane.
Explain how a neuron integrates incoming information, including a description of summation
The additive nature of potentials is called summation -sodium channels that trigger action potentials in the postsynaptic cell are near the axon hillock. If the membrane depolarizes at the axon hillock to threshold potential, voltage-gated sodium channels open to trigger positive feedback
Explain how a neuron integrates incoming information, including a description of summation.
The additive nature of potentials is called summation. Sodium channels that trigger action potentials in the postsynaptic cell are near the axon hillock. If the membrane depolarizes at the axon hillock to threshold potential, voltage-gated sodium channels open to trigger positive feedback.
Albuterol is a drug used by patients with asthma to dilate the airway. This drug is known to activate G alpha s-GPCR. As a result of administration of albuterol
The amount of ATP within the cell will decrease
Considering that sounds and odors both trigger changes in the patterns of action potentials from sensory cells, how does the brain perceive which sense is which when the action potentials reach the brain?
The axons from different sensory neurons go to different areas of the brain.
The primary stimulus for the secretion of ADH from the posterior pituitary is
The blood becoming too hyperosmotic
What would happen if an enzyme inhibitor for the enzyme photodiesterase (PDE) was applied to a vertebrate eye?
The cGMP-gated sodium channels would remain open, glutamate would be continuously discharged at the synapses, and the brain would not detect light absorbed by the rod cells.
A cell has just finished meiosis I. Which of the following is/are true?
The cell could move into interkinesis
You are looking at a cell using a high power microscope. The cell is still alive. You notice that the cell's nuclear envelope suddenly breaks down. Which of the following is a reasonable explanation for why the nuclear envelope broke down?
The cell entered prophase/prometaphase of mitosis
Many bodybuilders take a supplement known as creatine. Creatine is one of the few molecules capable of donating a phosphate group to ADP to form ATP. This formation of ATP is very quick and is thus very useful during strenuous weightlifting exercies when ATP is being rapidly consumed. AFter supplemental creatine has been absorbed into the blood stream, it enters skeletal muscles. How does this creatine affect the osmolarity of the muscle relative to the bloodstream?
The creatine will make the muscle hypertonic relative to the bloodstream, causing water to enter the muscle.
Which of the following characteristics must all gas exchange systems share?
The exchange surfaces must be moist.
How would the vision of a fly be affected if several of the axons extending from the ommatidia of its compound eye were damaged?
The fly would have reduced resolution in the affected eye.
What would occur if neurons simultaneously stimulated both the biceps and triceps muscles to contract?
The forearm would not move. These muscles pull in opposite directions; therefore, no movement would occur.
Administration of a drug that blocks voltage gated calcium channels would prevent
The fusion of vesicles with the synaptic terminal membrane
The hydrostatic skeleton of the earthworm allows it to move around in its environment by _____.
The hydrostatic skeleton of the earthworm allows it to move around in its environment by _____. using peristaltic contractions of its circular and longitudinal muscles
A pituitary adenoma is a non-cancerous tumor in the pituitary gland. Due to their location, these tumors can sometimes press on the optic nerve and impair a person's peripheral vision. Timmy has one of these tumors and decides to get it surgically removed to help restore his peripheral vision. However, after the surgery, he often feels far too cold or far too warm. Which of the following structures was most likely accidentally damaged during Timmy's surgery?
The hypothalamus
Why is the inflow of sodium ions into a photoreceptor cell called "the dark current"?
The inflow occurs when the receptor is not receiving light.
The vertebrate kidney is far more than an "Internal flush toilet!" In addition to ridding the body of nitrogenous waste, what other roles does the kidney play in maintaining animal homeostasis?
The kidney retains nutrients, blood proteins, NaCl, HCO3, Urea and water. It helps to regulate the PH of the blood and interstitial fluid by controlling what leaves the body.
True or False: Centrosomes and centrosome components are duplicated but remain together at one side of the nucleus during interphase.
True
True or False: Denaturing affects 3-D conformation of an enzyme and therefore it alters the active site and destroys enzyme activity
True
Which of the following best explains the evolution of adaptive camouflage in the pygmy seahorse?
The more the pygmy seahorse resembles the surrounding coral, the greater the seahorse's ultimate reproductive success.
If a neurotransmitter opens an ion channel allowing chloride ions to leave the cell, what is the consequence?
The neuron is more likely to reach an action potential.
What happens when a resting neuron's membrane depolarizes?
The neuron's membrane voltage becomes more positive
R. McNeill Alexander discovered that the arch of the human foot operates like a spring during running. Predict how a runner's oxygen consumption would change if a runner wore shoes that prevented the arches from changing shape.
The oxygen consumption of the runner would increase The oxygen consumption of the runner would increase because the arches of his or her feet would no longer store as much elastic energy, which normally reduces the energetic cost of running.
Arteries and veins are distinguished from one another by all of the following except?
The oxygen content of the blood they carry
Which of the following occurs during ventricular systole?
The pulmonary semi-lunar valve is open The bicuspid valve is shut
A molecule of CO2 is released into the blood in your foot, and is to be exhaled through your nose. To accomplish this, it must therefore pass through all of the following structures except?
The pulmonary vein
Demyelinating diseases, like multiple sclerosis, are devastating diseases that result in impaired motor function. This occurs due to the destruction of the myelin sheath around affected neurons. One of the common observations is that conduction velocity in affected neurons in reduced and in some cases action potentials do not travel to the axon terminal. Predict which of the following would explain why this disease has this effect. The sites of myelination do not have voltage-gated Na+ channels thereby preventing maintenance of the action potential as it propagates down the axon As myelin is lost, there is less ion leakage through the axon membrane The bare axon would conduct the signal much too rapidly to have an adequate effect onto muscle An axon that loses its myelination will not be able to generate any action potentials and would eventually die
The sites of myelination do not have voltage-gated Na+ channels thereby preventing maintenance of the action potential as it propagates down the axon The only location on a myelinated axon that has voltage-gated Na+ channels is in the nodes of Ranvier. It is at these locations that the action potential is maintained so that it can be propagated along the axon. In the myelinated regions, there are no voltage-gated Na+ channels. As a result, an axon that loses its myelination will have regions of axon that do not have any channels to help maintain the action potential. Action potentials will still be generated at the axon hillock, but they will not be able to make it to the axon terminal. This is because as the action potential moves into the demyelinated region, the charge will dissipate due to ion leakage and the action potential cannot be maintained due to the lack of voltage-gated Na+ channels.
What is the sliding filament model of muscle contraction
The sliding filament model means that the thick and thin filaments slide past each other to contract the muscle, without actually shortening any cells
What is the sliding filament model of muscle contraction? What is ATP used for? Which of the protein molecules (actin or myosin) actually bends to cause contraction? Do the myofilaments themselves contract? How is high-energy phosphate stored in the muscle? What happens if the muscle runs out of ATP?
The sliding filament model means that the thick and thin filaments slide past each other to contract the muscle, without actually shortening any cells. Myosin is bent when ATP is attached, Myosin straightens and attaches to actin when it is hydrolyzed to ADP and P. When P releases, Myosin bends, pulling the actin closer. ATP binds, and it releases the actin. When ATP is absent, the muscles can't release the actin and stiffen (rigor mortis)
The drug lidocaine is a local anesthetic that prevents pain transmission by binding to specific ion channels in nerve fibers. At low concentrations it decreases the rate of rise of the AP upstroke, and at high concentrations it completely prevents the AP. Which channel is blocked? The K+ leak channel. The voltage-gated Na+ channel. The voltage-gated K+ channel. The Cl- hyperpolarizing channel.
The voltage-gated Na+ channel.
Glutamate and GABA are very similar chemically, only differing by one carboxyl group, and many neurons have enzymes to convert back and forth between the two neurotransmitters. Given this, why do they produce vastly different effects, with glutamate typically being excitatory and GABA typically being inhibitory? They bind to different ionotropic receptors that are permeable to different ions (Cl- for GABA, mainly Na+ for glutamate). They bind to different active sites of the same ionotropic receptor, modulating the relative permeablity to different ions. The bind to different metabotropic receptors that converge on the same ion channel, stimulating channel opening. They bind to different ionotropic receptors that are permeable to different ions (Cl- for glutamate, mainly Na+ for GABA).
They bind to different ionotropic receptors that are permeable to different ions (Cl- for GABA, mainly Na+ for glutamate). They bind to different receptors which permit the flux of different ions (Cl- for GABA, mainly Na+ for glutamate).
Certain nutrients are considered "essential" in an animal's diet because
They cannot be synthesized by the animal and must be provided by food.
What does a gram stain indicate?
Thickness of wall through the presence of peptidoglycan
True or False: A slight change in primary structure can affect a protein's structure and ability to function
True
True or False: All mammals have an inverted retina
True
In all cells, the process where DNA is used to create mRNA is known as
Transcription
What are the roles of troponin and tropomyosin? How is their interaction with actin controlled?
Tropomyosin and troponin block the myosin binding sites, and stops myosin-actin interaction, allowing the muscle to relax. When calcium binds to troponin, it moves to expose binding sites on the actin.
Fill in: Calcium ions bind to regulatory proteins called ________ which results in tropomyosin uncovering myosin-binding sites
Troponin Compelx
True or False: A heart attack causes ischemia (death) of cardiac muscle cells, but a stroke refers specifically to a blockage or rupture of arteries in the head, resulting in the death of nervous tissue in the brain.
True
True or False: A skeletal muscle consits of a bundle of long fibers, each a single cell, running parallel t the length of the muscle.
True
True or False: In order for a specific hormone to effect a cell, the cell needs to have a receptor for that specific hormone.
True
True or False: Lipids do not form polymers
True
True or False: Prokaryotic cells have a cytoplasm bound by a plasma membrane
True
True or False: Someone with hyperthyroidism may appear thin, have difficulty regulating temperature, and have an overactive metbolism
True
True or False: Starch (storage polysaccharide of plants) consists of entirely of glucose monomers
True
True or False: Steroids are made from cholesterol, therefore they are lipid-soluble and bind with receptors in cytoplasm
True
True or False: a Skeletal muscle fiber contracts only when stimulated by a motor neuron
True
True or False: dehydration reaction synthesizes a polymer while hydrolysis (+ water) breaks a bond
True
True or false: Insects can see "in color"
True
True or False: Most ganglion cell axons lead to the geniculate nuclei
True (See figure 50.20 in ppt (or book))
True or False: Epinephrine requires a receptor at the surface of the cell
True (therefore, a 2nd messenger is needed)
True or False: The hemoglobin in the choroid layer is why a rat with albinism has red eyes
True - Choroid layer contains capillaries to supply eye structures with nutrients,
True or False: signals from the NS initiate and regulate endocrine signals
True - NS sends info to hypothalamus and initiates responses through endocrine system.
True or False: The brain controls what information in captured (visual information)
True - Think about how the brain "ignores" certain things you are looking at
True or False: Cholesterol can increase membrane fluidity depending on temperature
True - can also make it less fluid
True or False: Fats separate from water because water molecules form hydrogen bonds with each other and exclude the fats
True - they are nonpolar and hydrophobic
True or False: Target cells are cells with a receptor for a specific hormone and therefore are the cells that can respond to that specific hormone
True: Target cell for insulin has insulin receptors and can bind to insulin. Cannot respond to a hormone it does not have receptors for
Fill in: Phospholipid = two ______ and a ______ are attached to
Two fatty acids and a phosphate group attached to glycerol 2 fatty acid tails = hydrophobic Phosphate group and its attachment = hydrophilic head
Which of the following types of blood vessels contain(s) one-way valves?
Veins
"hot" peppers taste this way because of capsaicin. it is said to taste hot because it
activates the same receptors as something heated
At point D
Voltage gated potassium channels are open The membrane potential is depolarized
Which of the following is a direct result of depolarizing the presynaptic membrane of an axon terminal?
Voltage-gated calcium channels in the membrane open
In lab, you make a "Fake Cell" using a special balloon that is permeable to the water but not to sucrose. The ballon is filled with 20% sucrose and 80% water. You then place the balloon in a beaker containing a solution of 40% sucrose and 60% water. Which of the following will occur?
Water will leave the balloon.
In lab you use an "artificial cell" with a membrane that is permeable to water but not to sucrose. You fill the "cell" with a solution containing 20% sucrose and 80% water, and you place it in a beaker containing 40% sucrose and 60% water. Which of the following will occur?
Water will leave the cell
Describe two mechanisms by which a neurotransmitter affects the postsynaptic cell.
When a neurotransmitter binds to a ligand-gated ion channel, the channel opens and allows a flow of ions. Some bind to receptors that activate enzymes for production of a second messenger.
Write in: How does a stimulus depolarizing the membrane impact Na+ Channels?
When a stimulus depolarizes the membrane, Na+ channels open, allowing Na+ to diffuse in the cell increasing depolarization, which then makes even more Na+ channels open. With a strong enough stimulus, a great enough depolarization can result in a massive change in membrane voltage called an action potential
How is a person able to partially contract a muscle (such as the bicep), when the fibers of a motor unit completely contract when stimulated by a motor neuron? How is this related to recruitment?
When fewer muscle cells contract, the muscle contracts less. Slow fibers contract slowly because they hydrolyze ATP slow. Vice versa for Fast fibers,
What is the most important factor limiting the maximum size a single cell can attain? Explain why this factor limits the size
When the surface to volume ratio becomes too small due to the volume increasing much faster than the surface, the metabolic processes create too much toxins then can be transferred by the smaller surface area and not enough nutrients can be absorbed this environment rapidly becomes one that cannot sustain cell life.
What are the following parts of the sarcomere
Z line, A band, I band, H zone
signal transduction cascade
a chain of events that is activated by cAMP
holometabolous
a "complete" metamorphosis transition in some insects
which of the following could be associated with peristalsis?
a b and c
hormone
a chemical signal that circulates through body fluids and affects distant target cells
hormone
a chemical signal that circulates thru body fluids and affects distant target cells
steroids
a class of chemicals that can act as a hormone - a family of lipids distinguished by a four-ring structure
peptides and polypeptides
a class of chemicals that can act as a hormone - chains of amino acids linked together by peptide bonds
amino acid derivatives
a class of chemicals that can act as a hormone - substance that is synthesized from an amino acid
endocrine system
a collection of organs and cells that secrete chemical signals into the bloodstream
electrical potential / voltage
a difference in charge between any two points
nerve net
a diffuse network of neurons that conducts impulses in all directions from a point of stimulus --> found in jellyfish, hydra, anenomes, etc.
immunoglobulins (Ig)
a family of proteins that are crucial to the adaptive immune response BCR and antibodies produced by B cells are Ig's
node of Ranvier
a gap in the myelin sheath, have a lot of voltage-gated Na+ and K+ channels, generate new action potentials here, the action potentials "jump" from node to node down a myelin sheath
severe combined immunodeficiency (SCID)
a genetic disorder where the person lacks a normal immune system and are unable to fight off infections
compliment system
a group of proteins that are activated by antibodies that are bound to pathogens, circulate in the bloodstream and assemble at antigen-antibody complexes, when activated they punch deadly holes in the plasma membranes of pathogens
adrenaline (epinephrine)
a hormone produced by the adrenal glands that plays an important role in the fight-or-flight response by increasing blood flow to muscles, output of the heart, pupil dilation, and blood sugar synthesized from the amino acid tyrosine
cortisol
a hormone produced by the adrenal glands, that is released in response to stress and low blood-glucose concentration synthesized from the steroid cholesterol
melatonin
a hormone produced the pineal gland that relays photoperiodic information to the hypothalamus
aldosterone
a hormone released by the adrenal cortex when the sodium concentration in body fluids is low, increases reabsorption of sodium ions in the distal tubules of the kidney saves sodium
luteinizing hormone (LH) and follicle-stimulating hormone (FSH)
a hormone released by the anterior pituitary gland that enters the blood stream and stimulates the testes and ovaries to secrete testosterone and estradiol
gonadotropin-releasing hormone (GnRH)
a hormone released by the hypothalamus that begins puberty by stimulating the anterior pituitary gland to release LH and FSH
thyroid-stimulating hormone (TSH)
a hormone secreted by the pituitary gland that is caused by a signal from the brain, which stimulates the thyroid gland to produce T4 (thyroxin), which is then converted to T3 (triiodothyronine) at target tissues
growth hormone (GH)
a hormone that stimulates growth, cell reproduction, and cell regeneration in humans and other animals
macrophages
a large phagocytic cell that releases cytokines that recruit other cells to the wound site and stimulate other activities secrete chemokines kills invading cells by phagocytosis
Acetylcholine released into the junction between a motor neuron and a skeletal muscle binds to a sodium channel and opens it. This is an example of _____.
a ligand-gated sodium channel
muscle fiber
a long, thin muscle cell
self molecule
a molecule belonging to the host
adrenocorticotropic hormone (ACTH) - a.k.a. corticotropin
a molecule from the pituitary gland that stimulates adrenal glands to secrete glucocorticoids a.k.a. cortisol - released in response to the release of CRH - which is released by the hypothalamus
norepinephrine
a molecule released by some sympathetic nerves directly onto target cells that acts to increase the force of skeletal muscle contraction and the rate and force of contraction of the heart is a catecholamine
second messenger
a molecule that binds at the surface
cyclic AMP (cAMP)
a molecule that is the key ingredient in the activation of phosphorylase
menstrual cycle
a monthly reproductive cycle in the human female ovaries
inflammatory response
a multistep, innate immune response observed in an array of animals
striated muscle
a muscle tissue that has a banded appearance --> when there are sarcomeres in the muscles
how do myosin and actin interact?
a myosin molecule has a group of "tails" that are coiled around each other, and they have a group of "heads" that are bent to the side, these "heads" can each bind to an ACTIN molecule
which of the following is a sensation and not a perception?
a nerve impulse induced by sugar stimulating sweet receptors on the tongue
List some other possible neurotransmitters
acetylcholine dopamine serotonin glutamate
second messenger
a nonprotein signaling molecule that increases in concentration inside of a cell in response to a signaling molecule that binds at the surface
Müllerian inhibitory substance
a polypeptide hormone produced by the testes that prevents the development of the female reproductive tract
vaccine - act = vaccination
a preparation containing antigens from a weakened or altered pathogen, mimicking an infection and priming the body's immune system to effectively fight off a later encounter with the unaltered pathogen
phagocytosis
a process of phagocytes in which they destroy invading cells by engulfing (eating) them
human immunodeficiency virus (HIV)
a progressive failure of the immune system, it infects and kills macrophages and CD4 T-cells
B-cell receptor (BCR)
a protein on the surface of B cells that are specific to certain antigens, and produce specific antibodies
T-cell receptors (TCR)
a protein on the surface of T cells that use other cells to bind to antigens
ion channel
a protein that forms a pore in the membrane through which specific ions can diffuse
action potential
a rapid, temporary change in a membrane potential --> happens when neurons are stimulated, allows them to communicate with neurons, muscles, or glands
How is high-energy phosphate stored in the muscle
a reserve of high-energy phosphate is stored in muscle as phosphocreatine, adenosine triphosphate and glucose 6-phosphate
immunity
a resistance to or protection against a disease-causing pathogen
which of the following would be expected to expend the greatest amount of energy for locomotion per unit mass?
a robin
which of the following is perceived as umami?
a savory complex cheese
epitope
a selected region of an antigen where antibodies, BCRs, and TCRs bind
mucus
a slimy mix of glycoproteins and water that traps pathogens and sloughs off
amplification of hormone signal
a small number of hormone molecules produces a large change in the activity of target cells and tissues
what do the responses of epinephrine (adrenaline) lead to?
a state of heightened alertness and increased energy use that prepares the body for rapid and intense action such as fighting or fleeing
what is the structure diagrammed in figure 50.1?
a statocyst
corpus luteum
a structure that forms from the ruptured follicle and degenerates if fertilization does not occur
toll-like receptors (TLRs)
a subset of a larger group of proteins called pattern-recognition receptors which serve as sentinels to signal the presence of molecules associates with pathogens
Toll-like receptors (TLRs)
a subset of pattern-recognition receptors
Define neuromodulator, and describe how it may affect nerve transmission
a substance other than a neurotransmitter that is released by a neuron and transmits into to other neurons
bone marrow
a tissue that fills the internal cavities in bones
patch clamping
a way to study individual ion channels, done by touching a tiny patch of axon membrane with a fine tipped micro electrode and applying suction to capture a single ion channel w/ the electrode's tip
mast cells
a white blood cell that releases histamine, and other signals that increase blood flow to the wound area
How many centrosomes are in the cell at the beginning of G1? a. 1 b. 2
a. 1
What contributes to the negative charge within the neuron? a. Anions b. Cations c. Potassium d. Sodium
a. Anions - any of these trapped in the cell = contribute to negative charge. Anion = negatively charged ion
What is true regarding epinephrine a. Behaves like a protein/peptide hormone b. Behaves like a steroid c. Does not require a second messenger d. Can pass through the cell membrane e. A, C & D only f. B, C, & D only
a. Behaves like a protein/peptide hormone Therefore, cannot pass through cell membrane and requires a second messenger.
Where and when are peptide bonds formed? a. Between amino acids during protein synthesis on the ribosomes b. Between the R groups during protein folding in the Golgi c. Between the α carbons during protein synthesis on ribosomes d. Between the R groups during protein synthesis on ribosomes e. None of the above
a. Between amino acids during protein synthesis on the ribosomes
If you are seeing color, then what part of the retina is responsible? a. Central b. Peripheral c. Right side d. None of the above
a. Central (where the cones are concentrated)
The ion channels in the plasma membrane converts______ potential to _______ potential a. Chemical; electrical b. electrical; chemical c. Electrical; physical d. Chemical; physical
a. Chemical; electrical Chemical Potential Energy = Concentration gradients of K+ and Na+ across plasma membrane (maintained by sodium-potassium pumps using ATP energy)
What proteins mediate the cohesion of sister chromatids during mitosis a. Cohesins b. Myosin c. Actin d. Microtubules
a. Cohesins
What is false about DNA a. DNA directly controls protein synthesis b. DNA provides directions for its own replication c. DNA directs synthesis of messenger RNA (mRNA) d. Protein synthesis occurs in ribosomes
a. DNA directly controls protein synthesis DNA directs synthesis of mRNA, and through mRNA, controls protein synthesis
Signals that must travel through the blood describes what signaling system? a. Endocrine b. Paracrine c. Exocrine d. Autocrine
a. Endocrine
What binds to receptors on the plasma membrane of liver cells which then triggers the release of messenger molecules that activates enzymes and result in the release of glucose into the bloodstream? a. Epinephrine b. Amylase c. Glucagon d. Insulin
a. Epinephrine
Insulin is released using a. Exocytosis b. Endocytosis c. Pinocytosis d. None of the above
a. Exocytosis - protein hormones are synthesized by pancreatic beta cells, packaged into vesicles which fuse with plasma membrane, insulin is then released.
What accounts for cohesion and all the other properties of water? a. Hydrogen bonding b. Polar covalent bonds between oxygen and hydrogen c. nonpolar covalent bonds between oxygen and hydrogen d. None of the above
a. Hydrogen bonding
What process breaks a bond a. Hydrolisis b. dehydration c. Exocytosis d. Pinocytosis
a. Hydrolisis
Select all that apply: Which are endocrine glands? a. Hypothalamus b. Pineal gland c. Pituitary Gland d. Thyroid Glands e. Parathyroid glands f. Adrenal Glands g. Pancreas h. Kidney i. Heart
a. Hypothalamus b. Pineal gland c. Pituitary Gland d. Thyroid Glands e. Parathyroid glands f. Adrenal Glands g. Pancreas h. Kidney (also an organ containing endocrine cells)
What happens to living plant cells when exposed to salt solution? a. Lose water b. Gain Water c. Become more turgid d. Both B & C
a. Lose water
Which neurons activate skeletal muscles to respond? a. Motor b. Inter c. Skeletal d. Sensory
a. Motor
Where does acetylcholine stimulate skeletal muscle (aka striated muscle)? a. Motor nerve plate b. Osteon c. Tendon d. Sarcoplasmic reticulum
a. Motor nerve plate
When a muscle is at rest a. Myosin-binding sites on thin filament are blocked by tropomyosin b. Myosin-binding sites on the thick filament are blocked by tropomyosin c. Myosin is bound to actin d. Thin filaments are closer to the center of the sarcomere
a. Myosin-binding sites on thin filament are blocked by tropomyosin
Transcription (making messenger RNA from genes in the DNA takes place in the a. Nucleus b. Centromere c. Cytoplasm d. None of the above
a. Nucleus
What meets at the optic chiasm near the cerebral cortex? a. Optic Nerves b. Axons of photoreceptors c. Rods & Cones d. Bipolar Cells
a. Optic Nerves
_____ in the eye carry out the signal transduction necessary for vision. a. Photoreceptors b. Suspensory Ligaments c. Capillaries d. Crystalline Protein
a. Photoreceptors Key words = signal transduction
The ulna and radius connect at what type of joint? a. Pivot joint b. Ball-and-socket joint c. Hinge joint d. None of the above
a. Pivot joint Hinge example = humerus-ulna; ball & socket example = humerus-scapula
Glycosidic linkages are found in a. Polysaccharides b. Polypeptides c. Lipids d. Nucleic Acids
a. Polysaccharides
Which structure of a protein is its unique sequence of amino acids? a. Primary b. Secondary c. Tertiary d. Quaternary
a. Primary
Saltatory Conduction a. Process where action potentials in myelinated axons jump between the nodes of Ranvier b. Process where action potentials jump between myelin sheaths c. Process where action potentials steadily travel down the axon (do not jump) d. None of the above
a. Process where action potentials in myelinated axons jump between the nodes of Ranvier
_____ have a 6-membered ring and _____ have a 6-membered ring fused to a 5-membered ring a. Pyrimidines; purines b. Purines; Pyrimidines
a. Pyrimidines; purines
What rapidly terminates rigor? a. Rapid binding of ATP b. Rapid removal of ATP
a. Rapid binding of ATP
The neurons sodium/potassium ATPase a. Requires ATP b. Moves molecules across the plasma membrane along its concentration gradient b. Can work in the absence of ATP d. Directly stimulates muscle contraction
a. Requires ATP - moves molecules AGAINST their concentration gradient.
What has the maximum number of hydrogen atoms possible and no double bonds? a. Saturated fatty acids b. Triglyceride c. Unsaturated fatty acids d. All of the above
a. Saturated fatty acids
autocrine signals
act on the same cell that secretes them
what are the two types of protein found in sarcomeres?
actin and myosin
cyclic AMP (cAMP)
activates phosphorylase
Insulin is a large, charged, hydrophilic protein. Therefore, what is NOT true a. Second messengers are not needed to invoke a change in cell b. Insulin cannot pass through the phospholipid bilayer membrane. c. The hormone-receptor binding event occurs at the cell surface d. Signal transduction can only occur after insulin binds to a receptor.
a. Second messengers are not needed to invoke a change in cell Insulin is unable to pass through the phospholipid bilayer membrane (so B is true) and this means insulin requires a hormone receptor to be at the cell surface in order to complete the hormone-receptor binding even (so C is true). Since insulin cannot get through, a second messenger is needed to relay the signal into the cell nucleus. D is true for EVERY hormone stimulated cell change!
What is true about squid eyes a. Squid no not have an inverted retina b. Like humans, squid eyes begin development from brain and then makes contact with epidermal layer c Squid have an inverted retina d. A & B only e. B & C only
a. Squid no not have an inverted retina
Mitosis a. The process of chromosome segregation b. Consists of interphase, prophase, metaphase, anaphase and telophase. c. Results in Gametes and genetic change d. Both A & B only
a. The process of chromosome segregation
What is not true about graded potentials? a. They are brief all-or-nothing depolarization of a neuron's plasma membrane b. They are changes in polarization where magnitude of the charge varies with the strength of the stimulus. c. Summation of graded potentials can lead to an action potential d. Can depolarize or hyper-polarize the membrane
a. They are brief all-or-nothing depolarization of a neuron's plasma membrane
Stem cells that can become anything an embryo needs (aka become anything in the body), INCLUDING umbilical cord cells are what type of stem cell? a. Totipotent b. Multipotent c. Pluripotent d. Omnipotent
a. Totipotent
____ are liquid at room temperature and ____ are solid at room temperature a. Unsaturated fatty acids vs. Saturated fatty acids b. Saturated fatty acids vs. Unsaturated fatty acids
a. Unsaturated fatty acids vs. Saturated fatty acids
What is not true about oxytocin a. Uses negative feedback to regulate its hormonal pathway b. Induces uterine contractions and release of milk c. Is stimulated by suckling (suckling sends info to hypothalamus via NS) d. Oxytocin further stimulates milk glands
a. Uses negative feedback to regulate its hormonal pathway It's a positive feedback. Sucking = stimulus that releases oxytocin. Oxytocin is another stimulus that stimulates hypothalamus to tell posterior pituitary to releases more oxytocin.
The Na+/K+ ATPase pump a. Works at all phases of the action potential b. It sends 3 K+ ions outside and 2 Na+ ions inside the = c. Is a passive process d. Works only during the falling phase of an action potential
a. Works at all phases of the action potential B is wrong because it sends 3Na+ out and 2 K+ in C is wrong, it needs ATP to move Na+ and K+ against their concentration gradients D is wrong, it is ALWAYS working.
Thyroid Hormone is not a steroid, but behaves like one. Therefore a. it does not require a second messenger to exert its effects b. Requires a second messenger to exert its effects c. it is primarily responsible for all secondary male and female sex characteristics d. Is Hydrophilic
a. it does not require a second messenger to exert its effects
allergies
abnormal immune responses to antigens
List some other possible neurotransmitters.
acetylcholine Dopamine Serotonin Glutamate
epinephrine
adrenal glands adjacent to the kidneys release the is hormone also called adrenaline...inhibit contraction of muscle in the stomach and intestine... also known as adrenaline
mineralocorticoids
adrenal hormones that play a key role in homeostasis with respect to electrolyte concentrations and overall volume of body fluids
The middle ear converts _____.
air pressure waves to fluid pressure waves
peripheral nervous system
all neurons and other components of the nervous system outside of the CNS
peripheral nervous system (PNS)
all neurons and other components of the nervous system that are outside the CNS
lymphatic system
all of the ducts and organs involved in the production, maturation, and activation of lymphocytes
The all-or-none principle states that: all stimuli will produce identical action potentials. all stimuli great enough to bring the membrane to threshold will produce action potentials of identical magnitude. the greater the magnitude of the stimuli, the greater the intensity of the action potential. only sensory stimuli can activate action potentials. only motor stimuli can activate action potentials.
all stimuli great enough to bring the membrane to threshold will produce action potentials of identical magnitude.
heterotherms
allow body temp to rise or fall depending on conditions
voltage clamping
allows researchers to hold the voltage of a cell's plasma membrane at any desired value and record the electrical currents that occur at the voltage
sarcomeres
alternating light-dark units that repeat along the length of a myofibril
sarcomeres
alternation light-dark unites which repeat along the length of a myofibril
how does clonal expansion work in T cells?
an activated T cell divides repeatedly to produce genetically identical daughter needed because it leads to a large population of lymphocytes capable of responding specifically to the antigen that has entered the body
lysozyme
an antibacterial enzyme in your tears, they digest bacterial cell walls
multiple sclerosis (MS)
an autoimmune disease where the immune system targets oligodendrocytes, which destroys myelin sheaths in the CNS -- more damage causes the electrical signals to be impaired, dramatically affecting coordination and muscle strength
phosphorylase
an enzyme that catalyzes a reaction that cleaves glucose molecules off glycogen
adenylyl cyclase
an enzyme that is activated by a G-protein, role is to catalyze a reaction that converts ATP to cAMP
posterior pituitary
an extension of the brain - specifically the hypothalamus
exoskeleton
an exterior skeleton that encloses and protects an animal's body
autoimmunity
an immune response directed against molecules or cells that normally exist in the host these reactions often result in a disease due to the destruction of the body's own cells and structures multiple sclerosis (MS) - myelin sheath rheumatoid arthrititis - joints type 1 diabetes - insulin secreting cells
reflex
an involuntary response to an environmental stimulus
thymus
an organ located in the upper part of the chest in vertebrates
spleen
an organ located near the stomach in the abdominal cavity responsible for destroying old blood cells
gland
an organ that secretes specific molecules or solutions such as hormones or enzymes
pathogens
any disease causing bacteria, viruses, parasitic worms, fungi, and protists
antigen
any foreign molecule that can initiate an immune system response
why are differences in solubility of hormones important?
because steroids and thyroid hormones cross plasma membranes much more readily than do other types of hormones
intermediate muscle fibers
appear PINK or RED, between slow and fast fibers because they derive ATP from both glycolysis and aerobic respiration
slow muscle fibers
appear RED, high concentration of myoglobin, contract slowly because the myosin hydrolyzes ATP at a slow rate, fatigue slowly because many mitochondria specialized for endurance
fast muscle fibers
appear WHITE, low concentration of myoglobin, contract rapidly because the myosin hydrolyzes ATP at a rapid rate, fatigue quickly because few mitochondria specialized for bursts of activity
helper T cells
assist with the activation of other cells in the immune response
when an organism dies, its muscles remain in a contracted state termed "rigor mortis" for a brief period of time. which of the following most directly contributes to this phenomenon?
atp to break bonds between the thick and thin filaments
What is/are most concentrated in the fovea a. Rods b. Cones c. crystalline proteins d. A & B only
b. Cones
the axons of rods and cones synapse with
bipolar cells
Action potentials are primarily associated with the membranes of: dendrites only. cell bodies only. axons only. dendrites and axons. cell bodies and axons.
axons only.
A major function of glycoproteins in the cell's plasma membrane is to - incorrect a. Glue cells together to form tissues b. Allow cells in an embryo to recognize "like" cells so that they can sort themselves into tissues and organs c. Attach the cell membrane to the cytoskeleton d. Allow the cell to resist swelling e. Help maintain cell shape.
b. Allow cells in an embryo to recognize "like" cells so that they can sort themselves into tissues and organs
TTX: a. Blocks voltage-gated potassium channels b. Blocks voltage-gated sodium channels c. Increases frequency of action potentials to a dangerous level d. Both A & B
b. Blocks voltage-gated sodium channels (by binding to them!) Therefore, prevents depolarization and action potentials. No action potentials = nerves cannot send information to muscles which results in paralysis. Paralysis of respiratory tract can lead to respiratory arrest and death.
How are myosin-binding sites exposed? a. Ca++ binds to Tropomyosin b. Ca++ binds to Troponin complex c. The energy from ATP allows myosin to move tropomyosin d. None of the above
b. Ca++ binds to Troponin complex Troponin complex holds tropomypsin onto the myosin-binding sites. Once Ca++ binds to troponin,, the tropomyosin moves, exposing the myosin-binding sites.
What is the first and primary source of energy for living things? a. Lipids b. Carbohydrates c. Proteins e. Nucleic Acids
b. Carbohydrates
Where are sister chromatids attached? a. Centriole b. Centromere c. Centrosome d. None of the above
b. Centromere
What are responsible for the perception of color a. Rods b. Cones c. The photoreceptors located on the periphery of the retina e. All of the above f. A & C only
b. Cones
Pancreatic enzymes moving from the pancreas to the stomach uses what kind of signaling system? a. Autocrine b. Exocrine c. Paracrine d. Endocrine
b. Exocrine - the enzymes travel through a duct. Another example is bile traveling to stomach through duct.
When bicep relaxes and triceps contract: a. Forearm flexes b. Forearm extends
b. Forearm extends
Most neurons are nourished or insulated by cells called a. Golgi b. Glia c. Nodes of Ranvier d. None of the above
b. Glia
Which neurons put information together in brain? a. Motor b. Inter c. Cerebral d. Sensory
b. Inter
Eukaryotes, but not prokaryotes, have: a. DNA b. Internal membranes that divide the cell into different local environments which facilitates specific metabolic functions b. Cell membrane c. Ribosomes d. None of the above. These are true for BOTH eukaryotes and prokaryotes
b. Internal membranes that divide the cell into different local environments which facilitates specific metabolic functions
What is not true when you are looking at an object in the distance? a. Ciliary muscles relax and border of choroid moves away from lens b. Lens becomes thicker and rounder c. Suspensory ligaments pull against lens d. All of the above are true
b. Lens becomes thicker and rounder Lens becomes flatter when focusing on distant objects.
Neuron communication occurs as a. Long distance electrical signals; long distance chemical signals b. Long distance electrical signals; short distance chemical signals c. Short distance electrical signals; long distance chemical signals d. Short distance electrical signals; short distance chemical signals
b. Long distance electrical signals; short distance chemical signals
Stem cells that are partially differentiated are what type of stem cell? a. Totipotent b. Multipotent c. Pluripotent d. Omnipotent
b. Multipotent examples = stem cells in bone marrow. Have differentiated in that they will have something to do with blood, but can be RBC, WBC, Platelet, etc
A cell secreting a chemical signal to induce changes in nearby cells refers to which signaling system? a. Endocrine b. Paracrine c. Exocrine d. Autocrine
b. Paracrine cell stimulating surrounding cells at the cell-to-cell level****
Genes code for which macromolecule(s)? a. Polysaccharides b. Proteins c. nucleic acids d. All of the above
b. Proteins
Which structure (found in most proteins) consists of coils and folds in the polypeptide chain? a. Primary b. Secondary c. Tertiary d. Quaternary
b. Secondary
a single amino acid substitution in the protein hemoglobin can result in a. TaySachs b. Sickle-cell c. Parkinson d. MS
b. Sickle-cell
What is the storage polysaccharide of plants that consists entirely of glucose monomers? a. Glycogen b. Starch c. Sucrose d. Glucose
b. Starch Glycogen is the storage polysaccharide in animals - humans + other vertebrates store glycogen mainly in liver and muscle cells
Myosin molecule is attached to an actin filament in the a. The presence of ATP or ADP b. The absence of ATP or ADP
b. The absence of ATP or ADP The short-lived rigor state
What is NOT true about the lens a. Consists of crystalline protein b. The shape is controlled by the iris c. Becomes less flexible as we age d. Elongates or shortens depending on how far an object is
b. The shape is controlled by the iris Suspensory Ligaments and Ciliary Body are responsible for altering the lens shape.
In a mammalian neuron what is not true about resting potential a. The concentration of K+ is greater inside the cell b. There is a higher concentration of positive charge inside the membrane than outside the membrane of the neuron c. The inside of the cell is more negative than the outside Currents of K+ and Na+ are equal and opposite
b. There is a higher concentration of positive charge inside the membrane than outside the membrane of the neuron According to question 17 on Dr. Preston-Berlin's practice, a higher concentration of negative charge inside the membrane than outside the membrane is also false, but I want to check this! C is correct and allows the resting potential across the membrane to remain steady
What gland is critical in controlling the metabolism a. Goiter b. Thyroid c. Adrenal d. Pineal
b. Thyroid
why is summation so important?
because neurons receive input from many synapses, and because EPSPs and IPSPs sum up, information in the form of electrical signals is modified at the postsynaptic neuron before being passed on --> the action potential depends on the information the neuron receives from a wide array of other neurons
how can tiny amounts of hormones have such huge effects on an individual?
because of amplification through a signal transduction cascade
An abnormal shape in the lens or cornea results in a. optic chiasm b. astigmatism c. presbyopia d. amblyopia
b. astigmatism
regulation homeostasis
based on mechanisms that adjust the internal state to keep within limits that can be tolerated, no matter the external conditions
why would a blood transfusion with a different type of blood than the host not work?
because the host has different glycoproteins, and the glycoproteins of the new blood will be recognized by the immune system as an antigen, and will attack it
why does rigor mortis occur when an animal dies?
because the myosin and actin lock shortly after the animal dies, and ATP is needed to release the two molecules from each other, and no ATP is available in dead tissue, so they stay locked
luteal phase
begins with ovulation, and lasts an average of about 14 days 2nd part of the menstrual cycle
class 2
bind antigens inside endosomes
class 1
bind antigens inside the ER
what is the role of calcium in muscle contractions?
bind to the troponin complex, which leads to the exposure of the myosin-binding sites
During the contraction of a vertebrate skeletal muscle fiber, calcium ions _____.
bind with troponin, changing its shape so that the myosin-binding sites on actin are exposed
during the contraction of a vertebrate skeletal muscle fiber, calcium ions
bind with troponin, changing its shape so that the myosin-binding sites on actin are exposed
Uncontrolled diabetes can cause a person's blood to become very acidic. As a response to this acidity, the person would
breathe more quickly
endoskeletons
rigid structures that occur within the body, composed of rigid levers (bones) separated by joints
what is the most effective way for an animal to avoid getting an infection?
by preventing pathogens from entering their bodies in the first place
Which neurons receive information from sensors for external stimuli or internal conditions? a. Interneurons b. Motor Neurons c. Sensory Neurons d. Ganglia
c. Sensory Neurons
What is NOT true regarding motor neurons a. Each branched muscle fiber is innervated by one motor neuron b. Each motor neuron may synapse with multiple muscle fibers c. A motor unit consists of one muscle fiber and all of the motor neurons it is controlled by d. None of the above. All of the above are true regarding motor neurons
c. A motor unit consists of one muscle fiber and all of the motor neurons it is controlled by Motor unit consists of one motor neuron and all of the muscle fibers it controls
The myofibrils are composed of what two finds of filaments? a. Myosin (thin) and Actin (thick) b. Myosin (thick) and Laminn (thin) c. Actin (thin) and Myosin (thick) d. Actin (thin) and Desmin (thick)
c. Actin (thin) and Myosin (thick)
In Eukaryotic cells, the cytoskeleton consists of a. Microfilaments b. Microtubules c. All of the above d. None of the above
c. All of the above
Why are carrier transport proteins more like a ferry rather than a bridge? a. The conformation of the carrier transport does not change when solute molecule binds to it. b. Can let in more ions than channel proteins c. Carrier transport significantly changes conformation when a solute molecule binds to it. d. Can allow bigger molecules in like glucose
c. Carrier transport significantly changes conformation when a solute molecule binds to it. Like how ferries have a piece that allows cars to drive on. That piece is moved while ferry is on water and is replaced when it is time to unload ferry.
Chemical signals traveling through ducts describes what signaling system? a. Endocrine b. Paracrine c. Exocrine d. Autocrine
c. Exocrine
Charged, polar molecules are a. Hydrophobic b. Non soluble in water c. Hydrophilic d. Fat Soluble e. A, B & E Only
c. Hydrophilic - water-soluble
An increase in magnitude of the membrane potential is called a. Hypo-polarization b. Depolarization c. Hyper-polarization d.None of the above
c. Hyper-polarization
What does maintenance of resting potential depend on in neurons? a. Ligand-gated channels b. Voltage-gated channels c. Ionic Gradient d. All of the above
c. Ionic Gradient Ligand- and voltage-gated channels are responsible for generating an action potential
What allows an action potential to travel long distances? a. The size of action potential b. The frequency of an action potential c. It regenerates itself along the axon d. All of the above
c. It regenerates itself along the axon
What is the correct path of light in an inverted retina (aka a mammals retina)? a. Light encounters the rods and cones first and signal is then sent to optic nerves b. Light encounters Bipolar cells first, then ganglion cells, then rods and cones and signal is sent back to the optic nerve c. Light encounters optic nerve fibers first, then passes through ganglion cells, then bipolar cells, and then hits rods and cones and signal is then sent back to optic nerves. d. None of the above
c. Light encounters optic nerve fibers first, then passes through ganglion cells, then bipolar cells, and then hits rods and cones and signal is then sent back to optic nerves. Rods and Cones are at the very back of the retina. The first "layer" of the retina is actually the optic nerve fibers, then ganglion cells, then bipolar (and horizontal cells), then rods and cones (and then pigmented epithelium (the dark color of the retina)). This means light encounters optic nerves, ganglion cells, and bipolar cells before finally reaching the rods and cones and then signal is sent back through bipolar cells, ganglion cells, and finally optic nerve cells. If confused, this video was helpful https://www.youtube.com/watch?v=Pe14yECopOk
What signaling system is being described?: Neurotransmitters send local signal through a synapse a. paracrine b. Autocrine c. Nervous System d. Cell-Cell Contact Dependent e. Endocrine
c. Nervous System
What is the functional unit of the nervous system? a. Nephron b. Soma c. Neuron d. Nerve
c. Neuron
The enzyme responsible for ATP synthesis in cellular respiration is built into the mitochondrial membrane which shows how: a. Organelle membranes participate indirectly in cell metabolism b. Organelle membranes are not related to cell metabolism c. Organelle membranes participate directly in eukaryotic cell metabolism d. None of the above
c. Organelle membranes participate directly in eukaryotic cell metabolism - because many enzymes are build right into the membrane!
Which of the following would have the easiest time crossing the plasma membrane without the use of a transport protein? - incorrect. First thought was the right one. a. Insulin (C257H383N65O77S6) b. Hexacyanoferrate(II) ([Fe(CN)6]4+) c. Oxygen (O2) d. Potassium (K+) e. Glucose (C6H12O6)
c. Oxygen (O2)
Stem cells that can become anything an embryo needs (aka become anything in the body), NOT including umbilical cord cells are what type of stem cell? a. Totipotent b. Multipotent c. Pluripotent d. Omnipotent
c. Pluripotent
Which statement is not true a. Sensations from the left visual field of both eyes are transmitted to the right side of the brain b. Sensations from the right visual field of both eyes are transmitted to the left side of the brain c. Sensations from the left eye are transmitted to the right side of the brain only and sensations from the right eye are transmitted to the left side of the brain only d. The brain turns an image "right side up".
c. Sensations from the left eye are transmitted to the right side of the brain only and sensations from the right eye are transmitted to the left side of the brain only
Muscles are attached to bones by a. Ligaments b. Suspensory ligaments c. Tendons d. Osteons
c. Tendons
Which structure of a protein is determined by interactions among various side chains (R groups?) a. Primary b. Secondary c. Tertiary d. Quaternary
c. Tertiary
The name given to the arrangement of chromosomes at synapsis a. Karyotype b. Chromatids c. Tetrad d. None of the above
c. Tetrad
The strength of a stimulus can influence: a. The size of an action potential b. The duration of a single action potential c. The frequency of an action potential d. All of the above
c. The frequency of an action potential A bigger stimulus (e.g., smelling perfume in the glass vs. spraying it and letting it diffuse a bit) results in MORE action potentials. The stimulus does not impact the size of the action potential, just how many there are.
When your BGL (blood glucose level) falls low what happens? a. This stimulates beta cells of pancreas to release insulin b. This stimulates beta cells in pancreas to release glycogen c. This stimulates alpha cells of pancreas to release glucagon d. This stimulates alpha cells of pancreas to release glycogen
c. This stimulates alpha cells of pancreas to release glucagon
Rods allow for the perception of a. color b. the color red only c. black and white e. color and black and white
c. black and white
Correct order for sensory transduction in the eye: a. light induces conversion of trans-retinal to cis-retinal, cis-retinal activates rhodopsin, which activates G-protein, which leads to hydrolysis of cyclic GMP b. light induces conversion of trans-retinal to cis-retinal, cis-retinal activates rhodopsin, which leads to hydrolysis of cyclic GMP, which activates G-protein c. light induces conversion of cis-retinal to trans-retinal, trans-retinal activates rhodopsin, which activates G-protein, which leads to hydrolysis of cyclic GMP d. None of the above
c. light induces conversion of cis-retinal to trans-retinal (straightens retinal out (aka changes conformation)), trans-retinal activates rhodopsin (changes rhodopsin shape aka changes conformation), which activates G-protein, which leads to hydrolysis of cyclic GMP Great video: https://www.khanacademy.org/science/health-and-medicine/nervous-system-and-sensory-infor/sight-vision/v/phototransduction-cascade
What determines the primary structure of a protein a. size of a protein b. type of amino acids c. sequence of amino acids d. None of the above
c. sequence of amino acids
voluntary muscles
can contract in response to conscious thought, and are stimulated by neurons in the somatic division of the PNS
efferent division
carries commands from the CNS to the body
efferent division
carries commands from the CNS to the rest of the body, these neurons carry signals that allow the body to respond to changes in conditions in an appropriate way
phosphorylase
catalyzes a reaction that cleaves glucose molecules off glycogen
repolarization
changes the membrane potential back to negative, very rapid -occurs when the membrane potential reaches about +40 mV
cardiac muscle
cells contain sarcomeres and are striated, they have a unique branched structure and are directly connected end-to-end to intercalated discs makes up the walls of the heart, responsible for pumping blood throughout the body INVOLUNTARY --> parasympathetic (rest) and sympathetic (active) neurons
interneurons
cells in the CNS, pass signals from one neuron to another --> these integrate information from sensory neurons to the CNS
innate immunity
cells that are always ready inherent in ALL animals
adaptive immunity
cells that must first be selectively activated to tailor their response to a specific pathogen occurs in vertebrates and humans (6 months old and on)
follicle
cells that surround each developing egg in the ovaries -- surrounding cells
skeletal muscle
cells with exceptionally long, unbranched muscle fibers, enormous compared to other cells, they are packed with myofibrils, each having thousands of sarcomeres, giving it the STRIATED appearance exerts a pulling force on the skeleton, making it move VOLUNTARY --> somatic motor neurons cause them to contract
excitatory postsynaptic potentials (EPSP)
changes in postsynaptic cell that brings the membrane potential closer to threshold.
inhibitory postsynaptic potentials (IPSP)
changes in postsynaptic cell that makes the membrane potential more negative.
inhibitory postsynaptic potentials (IPSPs)
changes in the membrane potential of a postsynaptic cell that make the cell LESS LIKELY to produce an action potential
excitatory postsynaptic potentials (EPSPs)
changes in the membrane potential of a postsynaptic cell that make the cell MORE LIKELY to produce an action potential
excitatory postsynaptic potentials (EPSPs)
changes in the postsynaptic cell that bring the membrane potential closer to threshold
inhibitory postsynaptic potential (IPSPs)
changes in the postsynaptic cell that make the membrane potential more negative
repolarization
changes membrane potential back to negative
neurotransmitters
chemical messengers that transmit info from one neuron to another, or from a neuron to a target cell in a muscle/gland
neurotransmitters
chemical messengers that transmit information from one neuron to another neuron, or from a neuron to a target cell in a muscle or gland
second messengers
chemical signals produced inside a cell in response to a chemical signal that arrives at the cell surface
endocrine disruptor
chemicals that interfere with normal hormonal signaling
When moving from the back of the eye toward the front, the next layer immediately inside of the sclera is the
choroid
Ion channel inactivation is: closing of the channel in response to decrease in the stimulus. closing of the channel even when the stimulus continues. any type of channel closing None of the answers are correct.
closing of the channel even when the stimulus continues.
dendrites
collect chemical signals
endocrine system
collection of organs and cells that secrete chemical signals into the bloodstream
thick filament
composed of multiple strands of MYOSIN, they are the center of the sarcomere and both ends are free to interact with thin filaments
thin filament
composed of two coiled chains of ACTIN, one end is anchored to the Z-disc (the end wall of the sarcomere), then the other end is free to interact with thick filaments
which of the following is a correct statement about the cells of he human retina?
cone cells can detect color, but rod cells cannot
involuntary muscles
contract only in response to unconscious electrical activity and are stimulated and inhibited by neurons in the autonomic division of the PNS
BCR protein
consists of 2 polypeptides- a smaller light chain and a larger heavy chain
hydrostatic skeletons
constructed of an extensible body wall in tension surrounding a fluid or deformable tissue under compression
Motor neurons release the neurotransmitter acetylcholine (ACh) and acetylcholinesterase degrades ACh in the synapse. If a neurophysiologist applies onchidal (a naturally occurring acetylcholinesterase inhibitor produced by the mollusc Onchidella binneyi) to a synapse, what would you expect to happen?
convulsions due to constant muscle stimulation
Some persons with MS find that immersing their legs in a water bath increases their ability to walk for a while afterward. This is because the change in temperature improves action potential propagation along the axons. Would you expect a warming bath or cooling bath to improve signaling in MS patients with partially demyelinated axons? Warming Cooling
cooling. it prolongs the sodium current.
glucocorticoid
cortisol - referred to this because of its importance in regulating blood glucose concentration
glucocorticoid
cortisol... regulates blood glucose
The main function of most types of mammalian epithelial tissue is
covering body surfaces that are subject to mechanical injury, pathogens and fluid loss
What is considered a calcium storehouse? a) Haversian Canal b) Myosin-binding sites c) Lacunae d) Sarcoplasmic Reticulum
d) Sarcoplasmic Reticulum
Nervous System Signals can activate a. A gland b. Another neuron c. A muscle d. All of the above e. A & B only f. B & C only
d. All of the above
Skeletons function in a. Protection b. Movement c. Support d. All of the above e. A & C only
d. All of the above
What is NOT a role of the plasma membrane? a. Allows passage of oxygen b. Allows passage of nutrients c. Allows passage of waste d. All of the above
d. All of the above
What is true about GPCR's a. Mediate responses to a diversity of signaling molecules b. All have a similar structure c. Each is specific for a particular set of receptors and target enzymes d. All of the above e. A & C only
d. All of the above
What is true about chemical reactions a. Make and break bonds b. Starting molecules of a chem reaction = reactants c. final molecules of a chem reaction = products d. All of the above
d. All of the above
What is true about movement of water into/out of cell a. Movement is considered diffusion b. Facilitated by aquaporin protein channels c. Cannot pass through the fatty tails of the membrane without help because it is polar d. All of the above
d. All of the above
What brain structures play an important role in water reabsorption in kidneys and stimulating milk glands a. Hypothalamus b. Posterior Pituitary c. Anterior Pituitary d. All of the above
d. All of the above Hypothalamus makes the hormones and stores them in posterior pituitary. Hypothalamus regulates synthesis of hormones in anterior pituitary and secretion of hormones in posterior pituitary and anterior pituitary.
Each nucleotide consists of a a. Nitrogenous base b. Pentose Sugar c. Phosphate group d. All of the above e. A & C only
d. All of the above The portion of the nucleotide WITHOUT the phosphate group is called a nucleoside (so the nitrogenous base + sugar) SO Nucleotide = mucleoside = phosphate group
Contractions in smooth muscles a. Are relatively slow b. May be initiated by the muscles themselves c. May be stimulated by neurons in ANS d. All of the above are true e. None of the above are true
d. All of the above are true
What is not true about channel proteins a. Allows hydrophilic ions to pass through a membrane b. Almost specifically for ions c. Has ion specificity (one channel does not let in any kind of ion) d. Always open for passage e. Do not significantly transform shape to allow ion into membrane
d. Always open for passage Can be blocked to stop entry (by "tolls"). Once the toll is paid, TOLL CHANGES SHAPE and allows ion into channel protein.
Binding of a hormone to its receptor initiates a signal transduction which leads to a response in a. The cytoplasm b. Enzyme activation c. Change in gene expression d. Any of the above
d. Any of the above
When a cell stimulates itself, what signaling system is being used? a. Endocrine b. Paracrine c. Exocrine d. Autocrine
d. Autocrine Cell makes and secretes a chemical signal that binds to autocrine receptors on that same cell itself! Auto = self (like autopilot = self-driving car)
Which is part of the peripheral nervous system (PNS) a. Sensory input b. Motor Output c. Integration in the brain d. Both A & B
d. Both A & B (see figure 48-3 in action potential ppt.)
What generates the ATP needed to sustain muscle contraction a. Nitrogen fixation b. Glycolysis c. Aerobic Respiration d. Both B & C
d. Both B & C
What is NOT true about enzymes a. They are proteins made on ribosomes b. Have a precise tertiary conformation c. Lower the energy of activation for a reaction d. Can bind to any substrate
d. Can bind to any substrate - enzymes have strict substrate specificity
What signaling system is used when one cell binds to another to send a signal. a. paracrine b. Autocrine c. Exocrine d. Cell-Cell Contact Dependent e. Endocrine
d. Cell-Cell Contact Dependent Example: Helper T cells binding to B cells to get info on shape of antigen.
The similarities between human eyes and insects eyes supports what? a. Divergent Evolution b. We have evolved from insects c. Humans and Insects are closely related. d. Convergent Evolution
d. Convergent Evolution
What process forms a new bond a. Rehydration b. Hydrolisis c. Exocytosis d. Dehydration
d. Dehydration - lead to polymer or larger polymer
If you experimentally reduce the concentration of K+ in the extracellular fluid surrounding hair cells in the inner ear, the result would be like which of the following?
decreasing the volume of sound reaching the hair cells
The stomach lining produces a digestive enzyme known as pepsinogen. This enzyme must be secreted into the lumen of the stomach where it can be hydrolyzed into its active form, pepsin. Which of the following processes is responsible for the secretion of pepsinogen into the stomach lumen? - correct a. Endocytosis b. Pinocytosis c. Diffusion d. Exocytosis e. It could be either B or D
d. Exocytosis Endocytosis = taking in of matter by a living cell y invagination of its membrane to form a vacuole Pinocytosis = ingestion of LIQUID into a cell by the budding of small vesicles from the ell membrane Diffusion: movement of particles down their concentration gradient Exocytosis = cell transports secretory products thru the cytoplasm to the plasma membrane. Secretory products are packaged into transport vesicles
The location in the retina where central and color vision is at its highest acuity is the: a. Optic Disk b. Optic Chiasm c. Tapetum d. Fovea Centralis
d. Fovea Centralis
Alpha cells of Islets of Langerhans in pancreas produce _____ and beta cells produce _____ a. Glycogen; Insulin b. Insulin; Glucagon c. Insulin; Glycogen d. Glucagon; Insulin
d. Glucagon; Insulin
Muscle fiber contracts with concentration of calcium is _______ and muscle fiber contraction relaxes when calcium is ______ a. Low; High b. Low; Low c. High; High d. High; Low
d. High; Low
What is not true regarding hormones a. Require hormone-receptor binding for signal transduction b. Will bind either to receptors on the surface of cell or in the cytoplasm c. Travel through the blood (aka the endocrine signal system) d. Hormones will have the same effect on a cell if the cell as long as the cell has a receptor for that protein
d. Hormones will have the same effect on a cell if the cell as long as the cell has a receptor for that protein The type of cell depends on the effect. Example: Acetylcholine works at the surface of the cell and is secreted from the vagus nerve, different cell types have receptors for Acetylcholine: a. Can act on AV node and results in slowed heart rate. b. Can stimulate cell in salivary gland resulting in the secretion of amylase c. Can stimulate a skeletal muscle resulting in rapid contraction. Same hormone, but different effect based on the type of cell where the receptor is.
Tubulin is a ______ and microtubule is a ______ a. Monomer; monomer b. Polymer; polymer c. Polymer; monomer d. Monomer, Polymer
d. Monomer, Polymer
What is NOT true regarding steroids? a. They are lipid-soluble b. They do not require second messengers c. They bind to receptors in the cytoplasm which then allows them to change shape and "slip" into the nucleus where they can tell DNA to express different genes d. No statement is false. They are all true about steroids.
d. No statement is false. They are all true about steroids.
What is the point at which optic nerve fibers cross in the brain to ensure the images from the right and left eyes are sent to both the right and left side of brain. a. Optic Disk b. Fovea c. Corpus callosum d. None of the above
d. None of the above Correct answer is "optic Chiasm"
Leaky potassium channel is an ion channel therefore a. It undergoes a significant change in shape to let out potassium b. Requires ATP c. Brings potassium into the cell d. None of the above
d. None of the above Does not undergo a significant change, diffusion of potassium of of the cell is passive diffusion (no ATP needed)
At _____ the electrical current flows from one neuron to another neuron a. Chemical Synapses b. Neurotransmitter Synapses c. Only chemical current flows from one neuron to another neuron d. None of the above
d. None of the above This occurs at electrical synapses ALTHOUGH, most synapses are chemical synapses.
What is a 3-carbon alcohol with a hydroxyl group attached to each carbon? a. Glycogen b. Fatty Acid c. Glucagon d. None of the above
d. None of the above - this is describing glycerol Fatty acids . carboxyl group attached to a long carbon skeleton
During Hyper-polarization, gated potassium channels open, potassium diffuse _____ making the inside of the cell more ____. a. In; Positive b. In; Negative c. Out; Positive d. Out; Negative
d. Out; Negative
Movement of the chromosomes during anaphase would be most affected by a drug that a. Prevents elongation of microfilaments b. Prevents shortening of microfilaments c. Prevents elongation of microtubules d. Prevents shortening of microtubules e. Both A and D
d. Prevents shortening of microtubules
Which structure results when a protein consists of multiple polypeptide chains? a. Primary b. Secondary c. Tertiary d. Quaternary
d. Quaternary
Which part of the amino acid determines everything about the 3D structure of the protein? a. Amino group b. Carboxyl Group c. alpha carbon d. R group
d. R group
Which neurons send information to the brain? a. Motor b. Inter c. Cerebral d. Sensory
d. Sensory
What is a membrane potential? a. The voltage of a neuron not sending signals b. The voltage threshold for an action potential c. Increase magnitude of voltage d. The difference in charge (voltage) across its plasma membrane
d. The difference in charge (voltage) across its plasma membrane
What is the order of signal transduction in an endocrine signal a. Hormone, signal transduction, receptor binding, cell response b. receptor binding, hormone, signal transduction, cell response c. hormone signal, signal transduction, cell response, receptor binding d. hormone signal, receptor binding, signal transduction, cell response
d. hormone signal, receptor binding, signal transduction, cell response
DNA is a a. polypeptide b. amino acid c. Monopeptide d. nucleic acid
d. nucleic acid
inactivated viruses
damaged by chemical treatments hepatitis A and polio
helper T-cells
daughter cells of activated CD4 T-cells, these cells assist with the activation of other cells involved in the immune system
cytotoxic T-cells a.k.a. CTLs or killer T cells
daughter cells of activated CD8 T-cells, these cells kill cells that are infected with an intracellular pathogen
exocrine glands
deliver their secretions through outlets called ducts into a space other than the circulatory system
exocrine glands
deliver their secretions thru outlets called ducts into a space other than the circulatory system
acquired immune deficiency syndrome (AIDS)
developed from having previously being infected by HIV, people will succumb to illnesses that physicians almost never see in people with healthy immune systems
anterior pituitary
develops from cells in an embryo's mouth and throat lining
are epitopes for BCRs and TCRs on an antigen the same or are they different?
different - BCRs and antibodies bind to epitopes that are a part of the intact antigen, whereas TCRs bind to epitopes that have been processed and presented by other cells
pathogens
different disease causing bacteria,viruses, worms, fungi, protists, etc
neural signals
diffuse a short distance between neurons
paracrine signals
diffuse locally and act on nearby cells
What roles do polysaccharides have? a. Storage b. Structural c. Transport d. Defense against foreign substances e. A & B only f. A, B & C only
e. A & B only determined by its sugar monomers and positions of glycosidic linkages.
D-segments
diversity segments in the heavy chain, join later with J and V segments
What is the role of tubulin? a. Gives cells shape b. Allow for intracellular transport c. Blocks myosin-binding sites d. All oft he above e. A & B only
e. A & B only
Where are hormone-receptor binding events? a. Cytoplasm b. Cell Surface c. Out side of cell d. All of the above e. A & B only
e. A & B only
What can happen to a neurotransmitter (NT) that is released due to an action potential? a. NT may be degraded by enzymes b. NT may be taken up by surrounding cells c. NT may diffuse out of the synaptic cleft d. A & B only e. A, B & C
e. A, B & C
What is true when looking at an object that is near a. Ciliary muscles contract, pulling border of choroid toward lens b. Suspensory ligaments relax c. Lens becomes thicker and rounder d. A & B only e. A, B, and C
e. A, B, and C
What is true about nervous control of muscle tension> a. Contraction of a whole muscle is graded b. Extent and strength of contraction can be voluntarily altered c. NS can vary the # of muscle fibers that contract d. NS can vary the rate at which fibers are stimulated e. All of the above f. None of the above
e. All of the above
What do all cells have in common? a. They receive signals all of the time b. Survive c. Divide d. Differentiate e. All of the above f. C & D only
e. All of the above FYI: signals are what tells a cell to divide, differentiate, die. Therefore, all cells need to receive signals.
What are Myelin Sheaths made by? a. Nodes of Ranvier b. Glia-Oligodendrocytes c. Schwann Cells d. A & C only e. B & C only
e. B & C only
What occurs if gated Na+ Channels open and Na+ diffuse into the cell a. Reduction in the magnitude of the membrane potential b. Depolarization c. Hyper-polarization d.An increase in magnitude of the membrane potential e. Both A & B f. Both A & C g. Both B & D h. Both A & D
e. Both A & B Depolarization: charge is becoming less negative so getting closer to the 0mV charge outside of the cell
Which of these statements is false? a. Non-disjunction describes the event where chromosomes fail to separate during metaphase. b. Non-disjunction can lead to conditions such as Down's Syndrome c. A sperm missing chromosome 3 fusing with a normal egg would result in monosomy 3. d. An egg with two copies of chromosome 22 fusing with a normal sperm would result in trisomy 22. e. None of the above
e. None of the above
Interneurons a. Detect external stimuli b. Detect internal conditions (e.g., blood pressure) c. Leave brain or ganglia d. Trigger muscle activity e. None of the above
e. None of the above Interneurons integrate the info.
At the end of an action potential: a. The membrane depolarizes b. Stops right at the resting potential c. K+ are fast to close d. Na+ charged channels close e. None of the above
e. None of the above The neuron hyperpolarizes (undershoots). This is because K+ are SLOW to close (there's a delay). (Na+ charged channels close at the peak of the action potential which is why the potential only moves in one direction.)
Estrogen a. is charged b. is polar c. is Hydrophilic d. All of the above e. None of the above f. A & B only
e. None of the above Estrogen (and testosterone) = uncharged, non-polar, hydrophobic. Therefore, binds with receptors in the cytoplasm and then hormone-receptor complex moves into nucleus, binds to DNA and directly alters gene expression.
What holds water molecules together? a. Hydrogen bonding between hydrogens b. nonpolar covalent bonds between oxygen and hydrogen c. ionic bonds d. weak chemical bonds e. None of the above
e. None of the above - The polar covalent bond between hydrogen and oxygen hold water molecules together. Covalent bonds are STRONG
The area where axons of rods and cones come out of the retina to form the optic nerve is called the: a. Fovea Centralis b. Optic Chiasm c. Tapetum d. Ciliary Body e. None of the above
e. None of the above - this is the blind spot aka optic disk
Which is NOT found in both Eukaryotes and Prokaryotes a. Plasma membrane b. Ribosomes c. Chromosomes d. Cytosol e. None of the above. They are all found in both cell types
e. None of the above. They are all found in both cell types
where are endocrine signals produced?
either in glands, or in cells that are spread among the cells of another organ
what do hearing, touch, and a full stomach have in common?
electrical energy is transduced to form an action potential
what are animals with hydrostatic skeletons able to do that animals without exoskeletons or internal skeletons cannot do?
elongate
The absolute refractory period of an action potential: only ensures one-way travel down an axon. only allows a neuron to ignore a second signal sent that closely follows the first. only prevents summation of action potentials. ensures one-way travel down an axon and allows a neuron to ignore a second signal sent that closely follows the first. ensures one-way travel down an axon, allows a neuron to ignore a second signal sent that closely follows the first, and prevents summation of action potentials.
ensures one-way travel down an axon, allows a neuron to ignore a second signal sent that closely follows the first, and prevents summation of action potential
A skeletal muscle deprived of adequate ATP supplies will _____.
enter a state where actin and myosin are unable to separate
equilibrium potential
example with K+, when there is no longer a net movement of K+ inside or outside the cell
what do steroid and thyroid hormones tend to do? (summary)
exert their effects through changes in gene expression
why are there V regions of antibodies, BCR, and TCR?
explains why each of these proteins binds to a unique epitome
which of the following could you find in the lumen of a transverse tubule?
extracellular fluid
Which organ contains endocrine cells? a. Kidney b. Heart c. Small Intestine d. Stomach e A, C & D only f. A, B, C & D
f. A, B, C & D
What are the parts of an amino acid? a. R group b. α carbon c. carboxyl ends d. amino ends e. beta carbon f. A, B, C, & D only g. A, C, D, & E only e. A, C, & D only
f. A, B, C, & D only
In neurons, what can be signals that can cause changes in membrane potentials a. Chemicals b. Sound c. Blood levels of carbon dioxide d. Light e. A and C only f. A, B, C, D
f. A, B, C, D
What type of hormones require the hormone-receptor binding event to occur at the cell surface? a. Hydrophobic hormones b. Peptides/proteins (hydrophilic) c. Hydrophilic hormones d. Uncharged hormones e. A & B only f. B & C only g. B, C & D only
f. B & C only Cell-Surface = protein/peptides, hydrophilic, charged. Hydrophilic = water-soluble (they love water)
What are the receptors that cause fast, short responses at the postsynaptic neuron and the receptors that cause slow, longer-lasting responses? fast: ionotropic; slow: channel-unlinked fast: metabotropic; slow: ionotropic fast: ionotropic; slow: metabotropic fast: metabotropic; slow: channel-unlinked
fast: ionotropic; slow: metabotropic
glucocorticoids have:
feedback inhibition... they suppress their own production
somatic hypermutation
fine-tunes the immune response
A muscle that swings two long bones in an arc toward each other is a ______, and an example is the ______.
flexor; hamstring muscle Flexors pull bones closer together, as the hamstring muscle in the leg contracts to articulate the tibia with the femur.
xenoestrogens
foreign chemicals that bind to estrogen receptors and induce estrogen-like effects
hypothalamic-pituitary axis
form two anatomically distinct systems because of the two segments of the pituitary gland: anterior and posterior pituitary
synaptic vesicles
found on the ends of axons, multiple sac-like structures, hypothesized to be storage sites for neurotransmitters
catecholamines
function as neurotransmitters as well as hormones
what is a muscle spindle?
groups of dendrite-encircled muscle fibers
what hormone stimulates the growth surge of puberty?
growth hormone (GH) produced by the pituitary gland
During an auditory transduction, ion flow varies across the _____.
hair cell membrane
the pathway leading to the perception of sound by mammals begins with the
hair cells of the organ of corti, which rests on the basilar membrane, coming in contract with the tectorial membrane
estrous cycle
happens in most mammals, where the lining of the uterus is reabsorbed if pregnancy does not occur
puberty
happens when humans reach early adolescence, surges of sex hormones that lead to the physical and emotional changes
signal transduction
happens with water-soluble messengers - must bind to receptors on the cell surface, so they never enter the target cell, so the message they carry must be changed (transduced) into a form that is active inside the cell
insulin
has the role of LOWERING glucose levels
glucagon
has the role of RAISING glucose levels
do action potentials greatly vary between species?
have the same general characteristics in all species and in all types of neurons
Hydra do not need a circulatory system because they
have thin body walls composed of only two layers
oxytocin
helps induce labor and milk release in female mammals
How does homeostasis relate to positive and negative feedback?
homeostasis is based on negative feedback; effectors reduce or oppose the change in internal conditions.
endocrine signals
hormones carried between cells by blood or other body fluids
neurohormones
hormones that are released fro neurons neuroendocrine signals
Which of the following is a muscular hydrostat?
human tongue The structure and function of the human tongue rely on pressurized internal fluid.
when light strikes the rhodopsin in a rod, retinal isomerises, initiating a signal transduction pathway that
hyperpolarises the rod, reducing its release of glutamate, which excites some bipolar cells and inhibits others
neurosecretory cells
hypothalamic neurons that synthesize and release neurohormones
lymphocytes are normally in a resting or inactive state
if it does not encounter an epitope that it is programmed to respond to, the cell eventually dies
secondary immune response
if the same antigen enters the body a second time, memory cells recognize certain epitopes of the antigen and trigger a second adaptive response
Tetrodotoxin blocks voltage-gated sodium channels and ouabain blocks sodium-potassium pumps. If you added both tetrodotoxin and ouabain to a solution containing neural tissue, what responses would you expect?
immediate loss of action potential with gradual loss of resting potential
Neural transmission across a mammalian synapse is accomplished by _____.
impulses causing the release of a chemical signal and its diffusion across the synapse
oligodendrocytes
in CNS, the specialized accessory cells that support neurons... called glia... form myelin sheath
where are all lymphocytes produces?
in bone marrow
estradiol
in females, the ovaries produce this steroid hormone that is in the family of molecules called estrogens... required for further development of reproductive tract
lysozyme
in tears, protection of eyes... acts as antibiotic by digesting bacterial cell walls
when does maximum melatonin secretion occur?
in the dark, which means stimulation of the pineal gland REDUCES melatonin secretion
what are the structural differences between inactive and active B cells?
inactive - large nucleus, little cytoplasm, few mitochondria, ruffled plasma membrane active - lots of rough ER and a lot of mitochondria need more rough ER to manufacture and secrete antibodies
central nervous system
includes large numbers of neurons aggregated into clusters called ganglia... includes brain and brainstem
photoperiod
increase in day length, important in stimulating the release of sex hormones in seasonally reproducing mammals, lizards, and birds... send signals to hypothalamus
Exercise and emergency reactions include _____.
increased activity in the sympathetic, and decreased activity in the parasympathetic divisions
what is puberty directed by?
increased levels of testosterone in boys and estradiol in girls
amplification
increases signal
How do sharks sense magnetic fields?
indirectly via electric fields Sharks have highly sensitive electroreception that researchers believe permits them to detect and orient to Earth's magnetic fields.
neurons
individual nerve cells, responsible for the working of the brain and the rest of the body -send electrical signals as fast as 270 mph
what are sensillae?
insect taste receptors found on feet and mouthparts
what ions are found inside and outside neurons?
inside: K+ ions --> want to go out because there is a lower concentration outside: Na+ and Cl- --> want to go inside cell because lower concentration
what are two major paracrine signals created by the pancreas, and where in the pancreas?
insulin and glucagon -- the islets of Langerhans
T cells
involved in graft rejection alone with an array of other immune functions including recognizing and killing host cells that are infected with a virus... mature in the thymus
follicle-stimulating hormone (FSH) and luteinizing hormone (LH)
involved in stimulating the gonads to produce sex hormone and gametes produced by the anterior pituitary
Thyroid hormone
is all of the below is lipid soluble Can freely pass through cell membranes controls the metabolic rate of the body
Bone
is mineralized by calcium and phosphate
subunit vaccines
isolated viral proteins hepatitis B and influenza
why is myelination (use of myelin sheaths on axons) such an important adaption?
it allows for rapid transmission of electrical signals possible in axons that have small diameters can increase speed by 15x
what does tetrodotoxin do to neurons?
it blocks the voltage-gated Na+ channel, making action potentials wiped out
what is the big fallback of long-term stress on the body?
loss of muscle mass -- causing severe weakness
Connective tissue is different from the other three major tissue groups because
it contains cells that are more sparsely scattered through a matrix of collagen fibers.
pituitary gland
it is located at the base of the brain, and produces a chemical signal that promotes cell division and other aspects of growth
why are membrane potentials usually negative?
it is measured in terms of inside relative to outside, and outside is 0 mV, so because there are usually more negatively charged ions and fewer positively charged ions on the inside surface relative to the outside
Where is calcium stored in the muscle
it is stored in the endoplasmic reticulum in NON-muscle cells
J-segments
joining segments of BCRs, TCRs, and antibodies
Red-green color blindness is caused by ______.
lack of a functional allele for one or more types of opsin molecules These M and L opsin molecules are found in M and L cones, either or both of which are lacking in color-blind individuals.
triglyceride is an effective energy-storage molecule because:
large amounts of ATP can be generated when its three fatty-acid subunits are oxidized... most stored in adipocytes
central nervous system (CNS)
large numbers of neurons grouped in clusters called ganglia
how does axon diameter affect speed?
larger diameters allow for cations moving down it to move quicker, with less resistance --> charge therefore spreads along the membrane quicker
which of the following contains mechanoreceptors that react to low frequency waves in much the same manner as our inner ear?
lateral line systems
neutrophils
leucocytes that move out of dialated blood vessels and migrate to the sight of infection, kill invading cells by phagocytosis
dendritic cells
leukocytes that gobble up antigens and debris via phagocytosis like messengers that collect information from the battle scene and then report to the lymph nodes, which then report to T cells
what do regulatory T cells do?
limit the intensity of normal responses by suppressing certain parts of the immune system also may help inhibit and self-reactive cells that slip through the self-educating system
steroids
lipid soluble, bind to receptors inside target cell
pituitary gland
locates at the base of the brain, directly connected to the hypothalamus = basis of connection between the CNS and endocrine system divided into anterior and posterior pituitary
nerves
long strands of nervous tissue made up of motor and sensory neurons
muscle fiber
long, thin muscle cell
what does low glucose and high glucose do to the body?
low - the brain does not have enough fuel to function high - toxic to neurons and blood vessels - can result in organ failure and amputation of extremeties
homeotherms
maintain constant heat; humans, birds, mammals
voltage-gated channels
membrane proteins that open and close in response to changes in membrane voltage
what is the difference between the menstrual cycle and the estrous cycle?
menstrual - the lining of the uterus is shed, goes OUT of the body estrous - the lining of the uterus is REABSORBED into the body
The "threshold" potential of a membrane is the _____.
minimum depolarization needed to operate the voltage-gated sodium and potassium channels
lymph
mix of fluid and lymphocytes
allergens
molecules that trigger allergic reactions
sensory cells
monitor conditions BOTH inside and outside the body
sensory cells
monitor conditions both inside and outside the body
amino acid derivatives
most not lipid soluble, bind to receptors on surface of target cell
muscle cells are stimulated by neurotransmitters released from the synaptic terminal of
motor neuron axons
The Na+/K+ pump
moves two potassium ions into cell
Multinucleate muscle cells vs. Uninucleate muscle cells
muscle cells may have one OR many nuclei depending on the size of the cells
which function associated with muscle would be most directly affected by low levels of calcium?
muscle contraction
what is the progression from a muscle down to its smallest component?
muscles, muscle tissue, bundle of muscle fibers, muscle fiber, myofibril, sarcomeres
trade off for being large
must find new ways to absorb nutrients must find ways to excrete waste
which of the following does not form part of the thin filaments of a muscle cell?
myosin
Where are actin and myosin located in the sarcomere
myosin is the prototype of a moecular motor- a protein that converts chemical energy in the form of ATP to mechanical energy IE muscle contraction. The actin cytoskeleton is responsible for the crawling movements of cells across a surface
motor neurons
nerve cells that send signals to effector cells in glands/muscles
motor neurons
nerve cells that send signals to the effector cells in glands or muscles
glia
nervous system cells that support neurons Ex. - Schwann cells and oligodendrocytes
excitable membranes
neurons are capable of generating action potentials that propagate rapidly along the length of their axons
electrical signaling
neurons transmit electrical signals, muscles can respond to signals from neurons by contracting
neural signals
neurotransmitters, diffuse across a short distance between neurons
peptides and polypeptides
not lipid soluble, bind to receptors on surface of target cell
cones
not sensitive to faint light, but stimulated by different wavelengths (color)
what portion of the brain has neurons that receive action potentials from chemoreceptor cells in the nose?
olfactory bulb
Olfaction occurs when airborne molecules trigger _______ in the nose, which send signals to regions in the olfactory bulb called _______.
olfactory neurons; glomeruli Each of the nose's chemosensory neurons has one type of odor receptor protein; neurons with the same type of receptor are linked to glomeruli in the olfactory bulb.
which of the following sensory receptors is incorrectly paired with its category?
olfactory receptor to electromagnetic receptor
which of the following is a good example of sensory adaptation?
olfactory receptors ceasing to produce receptor potentials when triggered by the smell of the second batch of cookies you are baking
refractory state
once Na+ sodium channels have opened and closed, they are less likely to open again for a short period
diurnal species
one that is active during the day
Two fundamental concepts about the ion channels of a "resting" neuron are that the channels _____.
open and close depending on stimuli, and are specific as to which ion can traverse them
how do sodium ion channels behave?
open quickly, for about a millisecond, when the membrane is depolarized, then close and remain inactive for 1 - 2 milliseconds
glands
organs that produce endocrine signals
endocrine glands
organs that secrete a hormone into the bloodstream
what impact would a nonfunctioning statocyst have on an earthworm? the earthworm would not be able to
orient with respect to gravity
which of the following receptors is incorrectly paired with the type of energy it transduces?
pain receptors to electricity
interneurons
pass signals from one neuron to another- integration
axon
passes chemical signals to dendrites of another cell of to an effector cell
The afferent and efferent axons together form the _____________. The brain and spinal cord together compose the ______________. central nervous system, peripheral nervous system. autonomic division system, somatic motor division of the nervous system. somatic motor division of the nervous system, central nervous system. peripheral nervous system, central nervous system. visceral nervous system, central nervous system.
peripheral nervous system, central nervous system.
A patient is transported to the ER after being trapped in a burning house. there are no burns on the patient's skin, but you want to make sure that the patient did not inhale any hot particles. You insert a bronchoscope into the patient's throat and you see two holes; one hole leads to the esophagus and the other leads to the trachea. because you are able to see both openings, you know the scope is located within the
pharynx
retinal
pigment that is associated with opsin
neurotoxins
poisons that affect neuron function
neurotoxins
poisons that affect neuron function - result in convulsions, paralysis, and unconsciousness
The hydrogen atoms of a water molecule are bonded to the oxygen atom by __________ bonds, while neighboring water molecules are held to together by __________ bonds.
polar covalent.....hydrogen
K+ leak channels
potassium channels that allow K+ to leak through the membrane, neurons have a relatively high amount of these
sympathetic nervous system
prepare organs for stressful "fight or flight" situations Ex. - speed up heart rate, stimulate the release of glucose from the liver, inhibit action by digestive organs
Sympathetic nervous system
prepares for fight or flight -speeds up heart rate, stimulates release of glucose from the liver, inhibits action by digestive organs
sympathetic nervous system
prepares for fight or flight; speed up heartrate, stimulate release of glucose from the liver, inhibit action by digestive organs
contraception
preventing unwanted pregnancies
which of the following structures is the last one that sensory information would encounter during visual processing?
primary visual cortex
B cells
produce antibodies... mature in bone marrow
growth hormone (GH)
produced in the pituitary gland... regulates growth factors which are signals that control the cell cycle... growth originates in the epiphyseal plate, a small piece of cartilage separating the shaft from the end at both extremities of long bones
endotherm
produces adequate heat to warm its own tissues because basal metabolic rate is high; the heat given off by chemical reactions warms the body
parasympathetic nervous system
promote "rest and digest" functions that conserve energy Ex. - slow down the heart, stimulate activity in the digestive tract
humoral response
promoted by Th2 cells and involves the production of antibodies and other proteins secreted into the blood and lymph
parasympathetic nervous system
promotes rest and digest -slow heart rate, increase digestion
parasympathetic nervous system
promotes rest-and-digest; slow heartrate, increase digestion
enteric nervous system
proposed 3rd division of the PNS, interacts with autonomic nerves but can also function independently, plays a major role in digestion
skeletal systems perform 4 main functions:
protection, maintenance of body posture, re-extension of shortened muscles, transfer of muscle forces
tropomyosin and troponin
proteins in thin filaments that work together to block the myosin binding sites on action
pattern-recognition receptors
proteins that serve as sentinels that signal the presence of molecules associated with pathogens include Toll-like proteins
memory cells
provide a surveillance service after the original infection has been cleared... remain in spleen and lymph nodes
what structural features contribute most to the diverse adaptation for animal movement?
skeletal and muscular systems
if a stimulus is to be perceived by the nervous system, which part of the sensory pathway must occur first?
reception
ligand-gated channels
receptors that are also ion channels, they have a binding site for a specific ligand on the part of the channel protein that faces the synaptic cleft
hypothalamus
region in the brain that produces ADH
hypothalamus
region in the brain that responds to changes in blood temperature and electrical signals
ACTH
regulatory hormone... the adrenal cortex secretes glucocorticoids in response to ACTH released from the pituitary
corticotropin-releasing hormone (CRH)
released by the hypothalamus that stimulates cells in the pituitary gland to secrete ACTH into the bloodstream
erythropoietin (EPO)
released by the kidneys and other tissues when blood oxygen levels fall, stimulate the production of red blood cells a crucial component in the homeostatic system for blood oxygen levels
ectotherm
relies on heat gained from the environment
immunity
resistance to or protection against a disease-causing pathogen
immune system
responsible for defending against pathogens
Inhibitory postsynaptic potentials (IPSPs): result in local depolarizations. result in local hyperpolarizations. increase membrane permeability to sodium ions. prevent the escape of potassium ions. prevent the escape of calcium ions.
result in local hyperpolarizations.
Untreated diabetes mellitus can cause damage to the eyes. IN particular, it can cause damage to the light-sensing rods and cones. therefore, the damage would be largely confined to the _____________.
retina
Sensory transduction of light in the vertebrate retina is accomplished by _____.
rods and cones
Which of the following structures shortens when a muscle contracts?
sarcomeres The sarcomere shortens as the filaments slide past one another.
aldosterone
saves sodium...released from the adrenal cortex when sodium concentration in body fluids is low... increases reabsorption of sodium ions in the distal tubules of kidneys.. plays role in electrolyte concentrations and overall volume of body fluids = mineralocorticoids
antidiuretic hormone (ADH)
saves water... released from the pituitary gland, increases permeability of the kidney's collecting ducts to water causing water to be reabsorbed from urine and saved
antibodies
secreted proteins that bind to a specific part of a specific antigen
pineal gland
secretes the hormone melatonin
epitope
selected region on the antigen
transmission
sends the signal to CNS
rods
sensitive to dim light but not to color
immediately after putting on a shirt, your skin feels itchy. however, the itching stops after a few minutes and you are unaware that you are wearing a shirt. why?
sensory adaptation has occured
how is sensory information processed by the body?
sensory information is transmitted from the PNS to the CNS, then the CNS transmits a response back to the PNS in specific parts of the body by motor neurons
Define reflex and describe the pathway of a simple spinal reflex
sensory neurons stimulate interneurons in the spinal cord that directly stimulate motor neurons
what happens to sarcomeres when muscles contract?
shorten, then lengthen when it relaxes and an external force stretches the muscle
chemokines
signaling molecules that recruit other cells to the site of infection secreted by macrophages
neuroendocrine signals
signals share a key attribute with endocrine signals: they act on distant cells hormones that are released from neurons
autocrine signals
signals that affect the same cell that releases them
endocrine signals
signals that are carried to distant cells by blood or other bodily fluids
paracrine signals
signals that diffuse locally and act on target cells that are near the source cell
histamine
signals that tell blood vessels slightly further from the wound to dilate and become more permeable secreted by mast cells
lymph nodes
small, oval organs located all around the body that filter the lymph passing through them
which of the major senses responds by means of a very large gene family?
smell
In the digestive system, peristalsis is _____.
smooth muscle contractions that move food along the esophagus
axon hillock
sodium channels that trigger action potentials in the postsynaptic cell are located near the start of the axon
The operation of the sodium-potassium "pump" moves _____.
sodium ions out of the cell and potassium ions into the cell
memory cells
specialized daughter cells of activated B and T cells that provide surveillance service after the original infection has been cleared remain in the spleen and lymph nodes until they are needed
hormone-response elements
specific sites in DNA that steroid hormone-receptor complexes bind to
homeostasis
stability in the chemical and physical conditions within an animal's cells, tissues, and organs
volt
standard unit of electrical potential
testosterone
steroid hormone that induces early development of the male reproductive tract
target cells respond to a particular hormone because they contain a receptor for the hormone
steroid hormone-receptor complexes bind to specific sites in DNA called hormone-responses elements
estrogens
steroid hormones that direct the development of female secondary sex characteristics in many animal species
what do many of the hormones produced by the anterior pituitary do?
stimulate the production of other hormones
adipocytes
stimulated by insulin in the blood, responsible for removing glucose from the bloodstream
prolactin
stimulates mammary gland growth and milk production in mammals produced by the anterior pituitary
Cardiac muscle cells are both _____.
striated and interconnected by intercalated disks
All skeletal muscle fibers are _____.
striated and under voluntary control
organ
structure that serves a specialized function and consists of several tissues
Which of the following graded potentials will be most likely to generate an action potential? hyperpolarizing potential an inhibitory potential subthreshold potential suprathreshold potential
suprathreshold potential
MHC proteins
surface proteins responsible for presenting epitopes
Describe the location and function of interstitial fluid.
surrounds the cells of multicellular animals
Among these choices, the most energetically efficient locomotion per unit mass is likely _____.
swimming by a 100-kilogram tuna (bony fish)
norepinephrine
sympathetic neurons release this neurotransmitter... inhibit contraction of muscle in the stomach and intestine
a sustained muscle contraction due to a lack of relaxation between successive stimuli is called
tetanus
where is integration done in most homeostatic systems in the body?
the CNS - brain and spinal cord
sex hormone production is regulated by the hypothalamic-pituitary axis
the GnRH treatment induced surges in LH and FSH followed by poverty onset
why are we able to differentiate tastes and smells?
the action potentials initiated by taste receptors are transmitted to a separate region of the brain than those initiated by receptors for smell
summation
the additive nature of postsynaptic potentials
the size of EPSP and IPSP depends on
the amount of neurotransmitter that is released at the synapse at a given time... higher=larger... these are short-lived b/c neurotransmitters do not bind irreversibly to channels
threshold potential
the amount the charge must change in order for an action potential to occur - -65 mV to -55 mV
cytokines
the best-studied autocrine signal, they amplify the response of a cell to a stimulus can also act as paracrine signals because they can trigger responses by other nearby cells of the immune system
When a neuron is at its resting membrane potential
the cell is "leaky" to K+
smooth muscle
the cells are unbranched, tapered at each end, and organized in thin sheets --> lack sarcomeres UNSTRIATED - why they are smooth found in lungs, blood vessels, digestive system, urinary bladder, and reproductive system regulated by autonomic motor neurons --> INVOLUNTARY
electrochemical gradient
the combination of an electrical gradient and a concentration gradient
refractory state
the condition of once an ion channel opens and closes, they are less likely to open again for a short period of time
immunization
the conferring of immunity to a particular disease
transduction
the conversion of an external stimulus to an internal signal in the form of action potentials along sensory neurons
what is the force exerted by a muscle determined by?
the cross-sectional area of the muscle -- number of sarcomeres lined up side by side exerting a pull in synchrony
apoptosis
the deterioration of an infected cell
resting potential
the difference in charge across a neurons membrane when its not communicating with other cells
resting potential
the difference in charge across its membrane when a neuron is not communication with other cells or tissues
gonads
the early development sex organs of a vertebrate embryo
cephalization
the evolution of a bilaterally symmetric body with structures for information gathering and processing located at the head end
menstruation
the expulsion (ridding) of the uterine lining
ovaries
the female sex organs
sliding-filament model
the filaments slide past one another during a contraction - so the sarcomere shortens but there is no actual change in the lengths of the thin and thick filaments
electric current
the flow of charge for ions moving from a region of like charge to the region of unlike charge --> because like charges repel and unlike charges attract
testosterone
the hormone that controls development of male reproductive anatomy and stimulates reproductive behavior
what regulates gonadal hormone production?
the hypothalamus-pituitary axis
mucosa-associated lymphoid tissue (MALT)
the immune system cells that are found in mucous-secreting tissues
primary immune response
the initial adaptive response - the first time the host meets with a pathogen
what are the physical signs of an infected wound the direct consequence of?
the innate immune response acting to contain and eliminate the infection
larvae
the juvenile form of a species that undergoes holometabolous
immunological memory
the launching of a secondary immune response by means of memory cells faster and more efficient than the primary response because the presence of memory T and B cells increases the number of lymphocytes that have the correct antigen receptors, decreasing lag
what is the length change of a muscle determined by?
the length of its muscle fibers -- how many sarcomeres are lined up in a row in each fiber
adaptive immune response
the leukocytes involved can customize their response to the particular invader
lymphocytes
the leukocytes that carry out the major features of the adaptive immune response
constant (C) region
the light chain region on a myeloma that is virtually identical among all myelomas
variable (V) region
the light change region on a myeloma that is unique to other myelomas
estrous cycle
the lining of the uterus is reabsorbed if pregnancy does not occur... called being 'in heat'
testes
the male sex organs
depolarization
the membrane becomes less polarized (when there is a difference in charges inside and outside the membrane) than before -highly negative --> crosses 0 --> goes briefly positive
Hair cells in the vertebrate ear are responsible for transducing sound pressure waves. Ion channels in the hair cell membrane open when _____.
the membrane is distorted mechanically
estradiol
the most important estrogen in humans and other mammals
locomotion
the movement of an organism or cell from place to place under its own power allows animals to avoid predators, obtain food, water, mates and shelter
presynaptic neuron
the neuron at a synapse that DOES contains the synaptic vesicles
postsynaptic cell
the neuron or cell at a synapse that DOES NOT contain the synaptic vesicles
antigen presentation
the process of an antigen needing to displayed by other cells of the immune system in order for the T-cells to bind to the antigen
metamorphosis
the process of changing from an immature, aquatic larva to a sexually mature, terrestrial frog, toad, or salamander happens in amphibians
positive feedback
the occurrence of an event makes the same event more likely to occur good example is Na+ channels because once depolarization begins, the channels open and allow Na+ into the membrane making it more likely to occur
positive feedback
the occurrence of an event makes the same event more likely to recur
skeletal fibers may be classified as either oxidative or glycolytic. which of the following muscles would be called glycolytic?
the ones most easily fatigued
photoperiod
the period of time each day during which an organism receives illumination; day length important in seasonally reproducing mammals, lizards, and birds
if a baseball player is hit in the back of the head, which part of his brain would be the most likely injured?
the primary visual cortex
biomechanics
the principles of physics and engineering are applied to questions about the mechanical structure and function of organisms
somatic hypermutation
the process of fully activated B-cells migrating to the germinal center in the lymph node where DNA sequences that code for immunoglobulins undergo rapid mutations that modify the variable region of the receptors responsible for fine-tuning the immune response can generate BCRs that bind more tightly to antigens than those produced by bone marrow
what causes an allergic reaction?
the production of IgE antibodies
Purkinje cells are neurons located within the cerebellum that release the neurotransmitter GABA. they are the largest neurons of the body. Note how extensive the dendrites are in this picture. why might purkinje cells need such an elaborate system of dendrites?
the purkinje cells receive information from many different sources
action potential
the rapid, temporary change in a membrane potential... consists of a strong inward flow of sodium ions followed by a strong outward flow of potassium ions
which of the following is controlled by the magnitude of a receptor potential?
the rate of production of an action potential
the perceived pitch of a sound depends on
the region of the basilar membrane where the signal originated
What does the Goldman-Hodgkin-Katz equation take into account that the Nernst equation does NOT? the electrical charges of the ions the relative permeabilities of the ions the solubilities of the ions the sizes of the ions the temperature
the relative permeabilities of the ions
the same hormone and receptor can give rise to different responses in different target cells
the same chemical messenger can trigger different responses in cells from different organs or in cells at different developmental stages
Membrane potenial
the separation of charges in the electrical potential of a cell; a form of potential energy
membrane potential
the separation of charges in the electrical potential of a cell; a form of potential energy
membrane potential
the separation of charges when an electrical potential exists across a plasma membrane -measured in millivolts
membrane potential
the separation of charges when an electrical potential exists across a plasma membrane... form of potential energy
fight-or-flight response
the short-term reaction to stress that is triggered by the sympathetic nervous system
major histocompatibility proteins (MHC)
the surface proteins responsible for presenting the epitopes to T cells 2 types: class I and class II -class I: bind to antigens inside the endoplasmic reticulum (ER) -class II: bind to antigens inside endosomes
myosin
the thick filaments of sarcomeres
actin
the thin filaments of sarcomeres
synaptic cleft
the tiny space between the membranes of axons that allow cells the communicate
when calcium ions bind to troponin
the troponin-tropomyosin complex moves in a way that exposes the myosin binding sites on actin
which of the following is an incorrect statement about the vertebrate eye?
the vitreous humor regulates the amount of light entering the pupil
myelin sheath
the wrapping of an axon made up of oligodendrocytes or Schwann cells, acts as a type of electrical insulation prevents ions from leaking back out across the plasma membrane of an axon
all or none
there is no such thing as a partial action potential, all action potentials for a give neuron are identical in magnitude and duration, action potentials are always propagated down the entire length of the axon
why does your arm feel cold when you reach inside the fridge to get a bag of milk?
thermoreceptors send signals to the posterior hypothalamus
what happens once steroids (or other hormones) reach the nucleus of a target cell?
they affect gene transcription after they bind to their receptors - causing dramatic changes in the amount or timing of mRNA production by a large number of genes
how do hormone-based contraceptive methods work?
they deliver synthetic versions of progesterone or progesterone and estradiol, suppressing the release
it is very difficult to sneak up on a grasshopper and catch it because
they have compound eyes with multiple ommatidia
how do potassium ion channels behave?
they open w/ a delay during depolarization, then continue to flip open and closed until repolarization, then they remain closed
which of the following are shared by skeletal, cardiac, and smooth muscle?
thick and thin filaments
what are the two types of filaments?
thin filaments and thick filaments - these overlapped in the dark bands of sarcomeres, but not in the light bands
myofibrils
threadlike, contractile filaments
myofibrils
threadlike, contractile structures found within each muscle cell
synapses
tiny spaces at the junctions of neurons
which of the following is an attachment site between sensory hairs that open ion channels when the hairs bend?
tip links
A new antibiotic is found to kill 99.9% of a pathogenic bacterial population. Based on our discussion of natural selection and adaptation, the next generation coming from the antibiotic-treated bacteria would be expected
to be more resistant to the antibiotic
what is cortisol's primary role in humans?
to ensure the continuing availability of glucose for use by the brain during long-term stress
what does the decline in melatonin levels tell the hypothalamus?
to stimulate the testes and ovaries to make sex hormones, readying the body for reproduction
what is the correct sequence of events that would lead to a person hearing a sound?
transduction, amplification, transmission, integration
opsin
transmembrane protein in membrane of rods/cones
afferent division
transmits sensory info to the CNS
afferent division
transmits sensory information to the CNS, these neurons monitor conditions inside and outside the body
what do polypeptide and most amino-acid-derived hormones tend to do? (summary)
trigger signal transduction cascades that activate existing proteins (usually by phosphorylation)
what are the two proteins on thin filaments that work together to block myosin binding sights on actin?
tropomyosin and troponin
Action potentials are normally carried in only one direction: from the axon hillock toward the axon terminals. If you experimentally depolarize the middle of the axon to threshold, using an electronic probe, then _____.
two action potentials will be initiated, one going toward the axon terminal and one going back toward the hillock
what are TCRs made of?
two protein chains -alpha chain -beta chain are immunoglobulins
how do neurons use electrochemical gradients of ions?
use them across their membranes to power the signals that allow neurons to communicate with one another and with other cells
node of Ranvier
unmyelinated section of the axon
what nerve is responsible for slowing the heart rate?
vagus nerve
antidiuretic hormone (ADH)
well-studied neuroendocrine signal -- produced by cells in the hypothalamus -- act on cells in the collecting duct in the kidney to help regulate water excretion
when do action potentials begin?
when Na+ flows into the neuron
follicular phase
when a follicle matures in the menstrual cycle, lasts about 14 days 1st part of the menstrual cycle
conformation homeostasis
when an animal adapts to constant environmental conditions and cannot function properly outside (rock cod needs to stay in cold water)
why is it less useful to think of a behaviour as a linear series of sensing, analysing, and acting than as a continuous cyclical process?
when an organism is acting it may also be sensing and analysing other stimulus
how does the troponin-tropomyosin complex unbind from the thin filament, making contraction possible?
when calcium ions bind to troponin
the transduction of sound waves into action potentials takes place
when hair cells are bent against the tectorial membrane, causing them to depolarise and release neurotransmitters that stimulates sensory neurons
The transduction of sound waves into action potentials takes place _____.
when hair cells are bent against the tectorial membrane, causing them to depolarize and release neurotransmitter that stimulates sensory neurons
depolarized
when ion flows cause the interior to become more positive (less negative)
hyperpolarized
when ions cause the cell interior to become more negative than the resting potential
adaptive immune response
when leucocytes have the ability to customize their response to particular invaders, whether it be different species or different strains of the same species
heat-shock proteins
when temperature spikes denature proteins, heat-shock proteins are activated to speed up the refolding of proteins
primary sex determination
when the gonads of a vertebrate embryo become either testes or ovaries
CRH
when the hypothalamus releases CRH, it stimulates cells in the anterior pituitary to secrete ACTH into the bloodstream
hyperpolarization
when the membrane is slightly more negative than the resting potential
hyperpolarization
when the membrane potential is slightly more negative than the resting potential
negative feedback / feedback inhibition
when the product of a process inhibits its production
positive feedback
when the product of a process stimulates its production
how do hormones know which tissues to bind to?
when they are broadcast throughout the body through the bloodstream, they only act on cells that express the appropriate receptor (target cells)
epiphyseal plates
where growth originates in the body, small pieces of cartilage separating the shaft from the end at both extremities of long bones growth stops when these plates are replaced by bone, making growth impossible
pineal gland
where mammals send signals from the photoreceptors in the retina, release the hormone melatonin also regulates sleep-wake cycles
axon hillock
where the axon emerges from the cell body, holds sodium channels that trigger action potentials in a neuron
radioimmunoassay
where the quantity of hormone in a blood sample can be estimated by adding a radioactively labeled version of that hormone to a sample - the labeled and unlabeled hormones will then compete with each other for binding to an antibody
Striated muscle cells vs. Unstriated muscle cells
whether the muscle tissue has a banded (striated) appearance
The perceived pitch of a sound depends on _____.
which region of the basilar membrane was set in motion
leukocytes
white blood cells, the cells that are responsible for triggering the body's first response to pathogens
do heavy chains have V and C regions in myelomas?
yes
