Bio 235 Midterm 1
Which is prominent in physiology, especially homeostasis?
Negative feedback
________ is an amino acid at excitatory synapses whereas ________ is an amino acid at inhibitory synapses. a) Gamma-aminobutyric acid : glutamate b) Gamma-aminobutyric acid : glycine c) Glycine : aspartate d) Aspartate : glycine e) Glutamate : aspartate
d) Aspartate : glycine
Define reflex
- specific - involuntary - unpremeditated - unlearned - built-in RESPONSE
Match! 1.) Endocrine 2.) Paracrine 3.) Autocrine ---- a.) signal reaches neighboring cells via the ISF b.) signal affects the cell that synthesized the signal c.) signal reaches often - distant targets after transport in blood-hormones
1.) C 2.) A 3.) B
What are the 3 types of chemical messengers?
1.) Endocrine 2.) Paracrine 3.) Autocrine
The process of maintaining the internal environment in a state compatible for life is called ________, and it occurs primarily through ________. A) intrinsic control : homeostasis B) negative feedback : intrinsic control C) homeostasis : negative feedback D) intrinsic control : negative feedback E) positive feedback : intrinsic control
C) homeostasis : negative feedback
Which of the following descriptions INCORRECTLY describes the tissue type? A) Muscle tissue is specialized for contraction and generation of force. B) Epithelial tissue forms glands. C) Nervous tissue is specialized for transmission of electrical impulses. D) Connective tissue is specialized for exchange between the internal and external environments. E) Epithelial tissue lines the lumen of internal organs.
D) Connective tissue is specialized for exchange between the internal
What are the 3 types of muscle cells?
Skeletal (voluntary) Cardiac (involuntary) Smooth (involuntary)
The chemical force for which of the following ions is directed out of the cell? a) K+ only b) Na+ c) Ca2+ only d) K+ and Na+ e) Na+ and Ca2+ only
a) K+ only
Positive feedback
When a deviation from triggers events that reinforce the deviation.
Negative feedback
When a system's response opposes or reverses a deviation
Given a cation with an equilibrium potential of -55 mV. If the plasma membrane of the cell is permeable only to this ion, then which of the following best describes the resting membrane potential? a) -55 mV b) +55 mV c) -70 mV d) More negative than -55 mV e) More positive than -55 mV
a) -55 mV
An increase in the extracellular concentration of K+ a) Depolarization of resting nerve cells b) Hyperpolarization of resting nerve cells c) No change in the resting membrane potential
a) Depolarization of resting nerve cells
Heart rate is affected by the release of epinephrine by the adrenal medulla into the bloodstream. This is an example of a) Endocrine control b) Exocrine control c) Paracrine control d) Direct neural control e) None of the choices are correct
a) Endocrine control
The diffusion potential for Na+ a) Favors its movement into the cell at resting potential b) Favors its movement out of the cell at resting potential c) Is equal and opposite to the electrical potential acting on sodium at resting potential d) Is in the same direction as the diffusion potential for potassium e) Both favors its movement into the cell at resting potential and is equal and opposite to the electrical potential acting on sodium at resting potential are correct across a nerve cell membrane
a) Favors its movement into the cell at resting potential
Which of the following is an example of negative feedback? a) If blood pressure increases above normal, baroreceptors in major arteries detect the change and send signals to the brain. Certain areas of the brain then send signals to the nerves that control the heart and blood vessels to make the heart beat slower and the blood vessels increase in diameter, which in turn reduce the blood pressure. b) During a blood clot, platelets release ADP, which stimulates platelet aggregation, causing platelets to release more ADP. c) During an infection, the body temperature set point is increased. The hypothalamus communicates to skeletal muscles to shiver and to blood vessels to decrease blood flow to the skin, causing a rise in body temperature. d) At the time of birth, uterine contractions push the baby toward the cervix. Receptors in the cervix detect the pressure caused by the baby and cause the release of a hormone called oxytocin. This hormone stimulates stronger uterine contractions, which push more on the baby, causing an increase in pressure and another increase in oxytocin. The cycle continues until the baby is delivered from the mother. e) Consumption of caffeine increases urine output, causing dehydration.
a) If blood pressure increases above normal, baroreceptors in major arteries detect the change and send signals to the brain. Certain areas of the brain then send signals to the nerves that control the heart and blood vessels to make the heart beat slower and the blood vessels increase in diameter, which in turn reduce the blood pressure.
The resting membrane potential a) Requires very few ions to be distributed unevenly b) Is the same in all cells c) Is oriented so that the cell's interior is positive with respect to the extracellular fluid d) Occurs only in nerve and muscle cells e) None of the choices are correct
a) Requires very few ions to be distributed unevenly
In Alzheimer's disease, cholinergic neurons are lost in the CNS. Which glial cells are thought to participate in the removal of the degenerating cholinergic neurons and release inflammatory chemicals that further degenerate the cholinergic neurons? a) astrocytes and microglia b) astrocytes and ependymal cells c) ependymal cells and microglia d) astrocytes and Schwann cells e) oligodendrocytes and Schwann cells
a) astrocytes and microglia
As the amplitude of the excitatory postsynaptic potential increases above threshold, the time between each action potential will ________, thereby increasing the ________ of the action potentials. a) decrease : frequency b) decrease : amplitude c) increase : frequency d) increase : amplitude e) not be altered : amplitude
a) decrease : frequency
What tissue type lines internal hollow organs and external surfaces of the body, providing a barrier between the internal and external environment? a) epithelial tissue b) muscle tissue c) nervous tissue d) connective tissue e) reticular tissue
a) epithelial tissue
A change in the postsynaptic potential that brings membrane potential closer to threshold is called a(n) ________. a) excitatory postsynaptic potential b) inhibitory postsynaptic potential c) suprathreshold postsynaptic potential d) hyperpolarizing postsynaptic potential e) inhibitory presynaptic potential
a) excitatory postsynaptic potential
At a synapse, the binding of a neurotransmitter to its receptor results in the opening of chloride channels. In this synapse, the chloride equilibrium potential equals the resting membrane potential. This synapse would be ________ because opening chloride channels ________. a) inhibitory : increases the "leak" conductance b) inhibitory : hyperpolarizes the membrane c) inhibitory : depolarizes the membrane d) excitatory : increases the "leak" conductance e) excitatory : hyperpolarizes the membrane
a) inhibitory : increases the "leak" conductance
The fluid compartment with a high sodium concentration that contains only trace amounts of protein is called ________. a) interstitial fluid b) plasma c) intracellular fluid d) extracellular fluid e) intracellular and extracellular fluids
a) interstitial fluid
Extracellular fluid is composed of ________. a) interstitial fluid and plasma b) plasma and intracellular fluid c) interstitial fluid only d) plasma only e) intracellular fluid only
a) interstitial fluid and plasma
The electrochemical gradient for sodium across a membrane at rest is such that the net flux of sodium will be ________, thereby causing the cell's membrane potential to become more ________. a) inward : positive b) inward : negative c) outward : positive d) outward : negative e) at equilibrium : positive
a) inward : positive
The tissue type that generates mechanical force and movement, and whose activity is controlled both on a voluntary and involuntary level, is ________. a) muscle tissue b) epithelial tissue c) connective tissue d) nervous tissue e) skeletal tissue
a) muscle tissue
The binding of a neurotransmitter to its receptor at an inhibitory synapse can lead to the ________ of ________channels. a) opening : potassium b) closure : potassium c) opening : sodium d) opening : chloride e) opening : calcium
a) opening : potassium
The chemical synapse is bounded by the ________ neuron, from which neurotransmitters are released across the synaptic cleft, to the ________ neuron, where the receptors for that neurotransmitter are located. a) presynaptic : postsynaptic b) postsynaptic : presynaptic c) parasynaptic : postsynaptic d) presynaptic : parasynaptic e) terminal : presynaptic
a) presynaptic : postsynaptic
Neurotransmitters can be reused through the process of ________, where neurotransmitters are transported across the presynaptic membrane. a) reuptake b) regeneration c) recycling d) resynthesis e) receptor binding
a) reuptake
Metabotropic receptor-induced gating of ion channels requires more time to occur because ________. a) their gating is linked to a G protein b) the channels are slower to open c) intracellular calcium must increase before those channels will open d) ion channels linked to metabotropic receptors must move to the membrane before gating e) metabolic byproducts are required to open those channels
a) their gating is linked to a G protein
At rest, what is the relative contribution of the sympathetic and parasympathetic nervous systems to the regulation of homeostasis? a) Only the sympathetic system is active. b) Both systems are active but the parasympathetic predominates. c) Only the parasympathetic system is active. d) Both systems are active but the sympathetic predominates. e) Neither system is active.
b) Both systems are active but the parasympathetic predominates.
Physiology is the study of a) How two organisms interact b) How organisms function c) The spread of diseases d) The structure of the body
b) How organisms function
A burn patient ingests 100 grams of protein per day but is losing 110 grams of protein per day by various means. This patient is in a) Positive protein balance b) Negative protein balance c) Stable balance d) A state that can't be determined
b) Negative protein balance
Which of the following statements about synapses is FALSE? a) Communication across electrical synapses is bi-directional. b) Neurotransmitters move from one cell to another through gap junctions at an electrical synapse. c) Communication at chemical synapses is slower than at electrical synapses. d) Electrical synapses can be gated. e) Most synapses in the nervous system are chemical synapses.
b) Neurotransmitters move from one cell to another through gap junctions at an electrical synapse.
Which is not a connective tissue cell? a) Bone cells b) Skeletal muscle cells c) Blood cells d) Fat cells e) Both skeletal muscle cells and blood cells are correct
b) Skeletal muscle cells
The four broad categories of cells include those specialized for each of the following functions except a) Movement b) Synthesis of complex molecules c) Secretion d) Support e) Conduction of electrical impulses
b) Synthesis of complex molecules
Which of the following statements about homeostasis is FALSE? a) The extracellular fluid is maintained in a state compatible for life. b) The primary mechanism to maintain homeostasis is positive feedback. c) The organ systems work together to maintain homeostasis. d) Illness can result if homeostasis is disrupted. e) Homeostasis is the maintenance of the internal environment.
b) The primary mechanism to maintain homeostasis is positive feedback.
The movement of an electrical charge across a membrane describes ________. a) a resistance b) a current c) a potential difference d) a transistor e) a capacitance
b) a current
Tissue type that functions in the transport of specific molecules from one body compartment to another. a) muscle tissue b) epithelial tissue c) connective tissue d) nervous tissue e) reticular tissue
b) epithelial tissue
Nitric oxide is a ________ that functions as a neurotransmitter. a) catecholamine b) gas c) neuroactive peptide d) biogenic amine e) amino acid
b) gas
The ________ determines the extent of the error signal in a feedback loop, in order to initiate the appropriate response. a) sensor b) integrator c) effector d) set point e) regulated variable
b) integrator
Which of the following statements applies to autocrine regulation? a) Chemical regulators are released directly into blood vessels b) Chemical regulators released by cells affect the functional status of different kinds of cells in the vicinity of the secretory cell c) Chemical regulators affect the same cell that produced it d) Chemical regulators reach their site of action through a duct e) Chemical regulators are continuously released in constant amounts by the cell
c) Chemical regulators affect the same cell that produced it
Homeostasis a) Depends upon control systems that use primarily positive feedback b) Involves adjusting to the external environment in a process called acclimatization c) Depends upon the interaction of receptors, integrating centers and effectors d) Both depends upon control systems that use primarily positive feedback and involves adjusting to the external environment in a process called acclimatization are correct e) Is described by none of the choices
c) Depends upon the interaction of receptors, integrating centers and effectors
Epithelial cells a) Include fat-storing cells b) Act as anchors for body structures c) Form boundaries between body compartments d) Both include fat-storing cells and act as anchors for body structures are correct e) Include all of the choices are correct
c) Form boundaries between body compartments
Which of the following is not true about axon transport? a) It refers to the passage of materials from the cell body of a neuron to the axon terminals b) It refers to the passage of materials from axon terminals to the cell body of a neuron c) It refers to the transport of materials across the axonal membrane d) It is especially important for maintaining the integrity of neurons with long axons
c) It refers to the transport of materials across the axonal membrane
________ is a reflection of the unequal distribution of positive and negative ions across the plasma membrane. a) Chemical gradient b) Extracellular potential c) Membrane potential d) Chemical driving force e) Electrochemical driving force
c) Membrane potential
Which of the following best describes the electrochemical forces acting on sodium and potassium ions at the resting membrane potential of a typical neuron? a) Forces on both sodium and potassium ions are to move into the cell. b) Forces on both sodium and potassium ions are to move out of the cell. c) The force on sodium ions is to move into the cell, and the force on potassium ions is to move out of the cell. d) The force on sodium ions is to move out of the cell, and the force on potassium ions is to move into the cell. e) There is no force on either ion to move.
c) The force on sodium ions is to move into the cell, and the force on potassium ions is to move out of the cell.
In a resting neuron, a) The plasma membrane is freely permeable to sodium ion b) The concentration of sodium ion is greater inside the cell than outside c) The permeability of the plasma membrane to potassium ion is about 25 times greater than its permeability to sodium ion d) The plasma membrane is completely impermeable to sodium ion e) None of the choices are true
c) The permeability of the plasma membrane to potassium ion is about 25 times greater than its permeability to sodium ion
Which of the following is a functional classification of neurons that carry information from the peripheral axon to the central axon? a) interneurons b) efferent neurons c) afferent neurons d) bipolar cells e) multipolar cells
c) afferent neurons
The chemical force for which of the following ions is directed into the cell? a) potassium only b) sodium only c) calcium only d) both potassium and sodium e) both sodium and calcium
c) calcium only
The lumen of which of the following systems is part of the INTERNAL environment? a) gastrointestinal system b) respiratory system c) cardiovascular system d) urinary system e) gastrointestinal and urinary systems
c) cardiovascular system
What type of glial cell acts locally to maintain normal electrolyte composition of the cerebrospinal fluid? a) astrocytes b) oligodendrocytes c) ependymal cells d) microglia e) Schwann cells
c) ependymal cells
The concentration of sodium is greater in the extracellular fluid compared to the intracellular fluid. If the membrane potential was equal to the equilibrium potential for sodium, then what would be the direction of the electrochemical force acting on sodium? a) inward b) outward c) no force d) varies by cell e) varies based on concentration of potassium in the intracellular and extracellular fluids
c) no force
The ability of the sympathetic nervous system to produce widespread responses within the body is driven by the structural relationship between pre- and postganglionic neurons where ________. a) multiple preganglionic neurons innervate each ganglion, sending out individual postganglionic neurons b) one postganglionic neuron branches into many collaterals that affect multiple organs c) one preganglionic neuron sends collaterals to multiple ganglia, affecting multiple postganglionic neurons d) one preganglionic neuron can activate only one postganglionic neuron e) several preganglionic neurons activate a single postganglionic neuron
c) one preganglionic neuron sends collaterals to multiple ganglia, affecting multiple postganglionic neurons
At the resting membrane potential in a neuron, the membrane is most permeable to ________, which movesn________ the cell due to its electrochemical gradient. a) sodium : into b) potassium : into c) potassium : out of d) sodium : out of e) calcium : into
c) potassium : out of
Which of the following statements about sodium is FALSE? a) There is a chemical force driving sodium ions into the cell. b) At the resting membrane potential, there is an electrical force driving sodium ions into the cell. c) At the sodium equilibrium potential, there is an electrical force driving sodium ions out of the cell. d) At the potassium equilibrium potential, there is an electrical force driving sodium ions out of the cell. e) At the sodium equilibrium potential, the electrochemical force for sodium movement across the plasma membrane is zero.
d) At the potassium equilibrium potential, there is an electrical force driving sodium ions out of the cell.
Circadian rhythms a) Are entrained by light: dark cycles b) Allow homeostatic set points to be changed appropriately for the overall physiological circumstance (e.g., being awake or asleep) c) Are important for helping to avoid jet lag d) Both are entrained by light: dark cycles and allow homeostatic set points to be changed appropriately for the overall physiological circumstance (e.g., being awake or asleep) are correct e) Both allow homeostatic set points to be changed appropriately for the overall physiological circumstance (e.g., being awake or asleep) and are important for helping to avoid jet lag are correct
d) Both are entrained by light: dark cycles and allow homeostatic set points to be changed appropriately for the overall physiological circumstance (e.g., being awake or asleep) are correct
The concept of homeostasis a) Includes the concept of an error signal b) Refers to maintaining physiological functions in a stable condition c) Refers only to the regulation of body temperature d) Both includes the concept of an error signal and refers to maintaining physiological functions in a stable condition are correct e) Both refers to maintaining physiological functions in a stable condition and refers only to the regulation of body temperature are correct
d) Both includes the concept of an error signal and refers to maintaining physiological functions in a stable condition are correct
Which of the following descriptions INCORRECTLY describes the tissue type? a) Muscle tissue is specialized for contraction and generation of force. b) Epithelial tissue forms glands. c) Nervous tissue is specialized for transmission of electrical impulses. d) Connective tissue is specialized for exchange between the internal and external environments. e) Epithelial tissue lines the lumen of internal organs.
d) Connective tissue is specialized for exchange between the internal and external environments.
Which is not true of myelin? a) Is a fatty membranous sheath b) Is formed by glial cells c) Influences the rate of conduction of the electrical signal down an axon d) Myelin covers all parts of the neuron: axon, cell body and dendrites e) None of the choices are true
d) Myelin covers all parts of the neuron: axon, cell body and dendrites
The total body balance of a chemical substance depends upon a) The net gain of a substance b) The net loss of a substance c) The size of the chemical pool in the body d) The net gain of a substance and the net loss of a substance e) All of the choices are correct
d) The net gain of a substance and the net loss of a substance
Which of the following statements concerning the permeability of a typical nerve cell membrane at rest is true? a) The permeability to Na ion is very much greater than the permeability to K ion b) All of the K ion channels in the membrane are open c) The voltage-gated Na ion channels are inactivated d) The voltage-gated Na ion channels are closed e) None of the choices are true
d) The voltage-gated Na ion channels are closed
The potassium equilibrium potential is -94 mV. What does this mean? a) at the resting membrane potential of neurons, potassium is at equilibrium b) at -94 mV, the chemical force for potassium movement is zero c) at -94 mV, the electrical force for potassium movement is zero d) at -94 mV, the chemical force for potassium movement is opposed exactly by the electrical force e) at -94 mV, potassium movement is opposed exactly by sodium movement
d) at -94 mV, the chemical force for potassium movement is opposed exactly by the electrical force
What type of glial cell contributes to neurodegenerative diseases, such as Alzheimer's disease? a) astrocytes only b) ependymal cells only c) microglia only d) both astrocytes and microglia e) both ependymal cells and microglia
d) both astrocytes and microglia
The inverse of resistance is ________. a) voltage b) current c) impedance d) conductance e) flux
d) conductance
The membrane potential at which there is no net flux of an ion across the membrane is called that ion's ________. a) potential difference b) action potential c) resting membrane potential d) equilibrium potential e) graded potential
d) equilibrium potential
Which of the following physiological responses are associated with elevated sympathetic nervous system activity? a) enhanced digestion b) enhanced absorption of nutrients c) decreased heart rate d) increased contractile force of the heart e) inhibition of cardiovascular function
d) increased contractile force of the heart
What are the two extracellular fluid compartments of the body? a) intracellular fluid and interstitial fluid b) intracellular fluid and plasma c) intracellular fluid and blood d) interstitial fluid and plasma e) interstitial fluid and blood
d) interstitial fluid and plasma
The opening of ion channels that are stimulated by the binding of a neurotransmitter to its receptor on a neighboring neuron, and the subsequent movement of ions across that membrane, describes the development of a(n) ________. a) action potential b) presynaptic potential c) neurogenic potential d) postsynaptic potential e) cleft potential
d) postsynaptic potential
Closure of an ion channel will increase a cell membrane's ________, whereas ________ will decrease. a) permeability : resistance b) permeability : conductance c) electrical current : permeability d) resistance : conductance e) conductance : resistance
d) resistance : conductance
Which of the following factors does NOT directly affect the direction or magnitude of the electrical driving force? a) the sign of the membrane potential b) an ion's charge c) the amplitude of membrane potential d) the molecular weight of an ion e) the quantity of charge carried by an ion
d) the molecular weight of an ion
Hormones a) Are chemical regulators that are conveyed from one organ to another via the blood stream b) May be secreted by endocrine cells c) May be secreted by nerve cells d) Both are chemical regulators that are conveyed from one organ to another via the blood stream and may be secreted by endocrine cells are correct e) All of the choices are correct
e) All of the choices are correct
Shivering in response to a cold draft is an example of a) A homeostatic mechanism b) Negative feedback c) A physiological reflex d) A homeostatic mechanism and negative feedback e) All of the choices are correct
e) All of the choices are correct
Which of the following statements about biological rhythms is correct? a) Menstrual cycles are examples of circadian rhythms b) Circadian rhythms are driven by pacemakers entrained by light and dark cycles c) Jet lag is a result of desynchronization of the internal clock from external time cues d) Both menstrual cycles are examples of circadian rhythms and circadian rhythms are driven by pacemakers entrained by light and dark cycles are correct e) Both circadian rhythms are driven by pacemakers entrained by light and dark cycles and jet lag is a result of desynchronization of the internal clock from external time cues are correct
e) Both circadian rhythms are driven by pacemakers entrained by light and dark cycles and jet lag is a result of desynchronization of the internal clock from external time cues are correct
Feedforward regulatory processes a) Work in anticipation of changes in regulated variables b) Work in conjunction with negative feedback processes c) Lead to instability of the regulated variable d) Maximize fluctuations in the regulated variable e) Both work in anticipation of changes in regulated variables and work in conjunction with negative feedback processes are correct
e) Both work in anticipation of changes in regulated variables and work in conjunction with negative feedback processes are correct
As a membrane's permeability to a particular ion increases, membrane potential will move ________ that ion's ________. a) away from : electrical gradient b) away from : electrochemical gradient c) away from : equilibrium potential d) closer to : electrochemical gradient e) closer to : equilibrium potential
e) closer to : equilibrium potential
The opening of an ion channel increases a cell membrane's ________, whereas ________ will decrease. a) resistance : permeability b) permeability : conductance c) permeability : electrical current d) resistance : conductance e) conductance : resistance
e) conductance : resistance
Tight junctions between capillary endothelial cells in the central nervous system create the blood-brain barrier, thereby restricting what type of movement of molecules into the brain? a) active transport of lipophilic b) passive diffusion of hydrophobic c) facilitated diffusion of hydrophobic d) diffusion of lipophilic e) diffusion of hydrophilic
e) diffusion of hydrophilic
What separates the internal environment of the body from the external environment? a) skin b) walls of blood vessels c) membranes of blood cells d) plasma membrane of all body cells e) epithelium
e) epithelium
A ________ is a subthreshold change in membrane potential that decays as it travels away from its point of origin. a) polarization b) hyperpolarization c) depolarization d) action potential e) graded potential
e) graded potential
A ________ is a subthreshold change in membrane potential within the cell body that decays as it travels away from its point of origin. a) polarization b) hyperpolarization c) depolarization d) action potential e) graded potential
e) graded potential
At the resting membrane potential, the neuronal membrane is most permeable to ________, which moves ________ the cell due to its electrochemical gradient. a) sodium : into b) sodium : out of c) chloride : into d) potassium : into e) potassium : out of
e) potassium : out of
The repolarization phase of action potentials in neurons is due primarily to ________. a) increased activity of the Na+ b) sodium flow out of the cell c) sodium flow into the cell d) potassium flow into the cell e) potassium flow out of the cell /K+
e) potassium flow out of the cell /K+
The myelin sheath that coats an axon acts to ________. a) decrease ion permeability in the nodes of Ranvier b) increase leakage of ions across the membrane c) decrease axonal conduction velocity d) increase a membrane's ion permeability e) reduce a membrane's ion permeability
e) reduce a membrane's ion permeability
In chemical communication between cells, a ________ cell secretes a chemical messenger that binds to ________ on the ________ cell. a) gap : connexons : secretory b) secretory : connexons : gap c) secretory : connexons : target d) target : receptors : secretory e) secretory : receptors : target
e) secretory : receptors : target
The direction of change in the resting membrane potential, in response to a stimulus that initiates a graded potential, is dependent upon ________. a) that membrane's threshold potential b) the gating of potassium channels only c) the gating of sodium channels only d) the changes in ion concentration across the membrane e) the ion channels that are opened or closed
e) the ion channels that are opened or closed
What are the 4 types of cells
neuronal, muscle, epithelial, and connective tissue
Which two cells are excitable?
neurons and muscle cells
