phys lab midterm
What are the two extracellular fluid compartments in the body?
Interstitial fluid and plasma
Bulk transport: exocytosis and endocytosis
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Cerebral Cortex microscope
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osmosis
1.Water molecules do not carry a charge, so they can pass through the plasma membrane slowly. 2.This is the diffusion of solvent instead of solute, it is unique. a.Given a special name - osmosis b.Aided by channels in the membrane called aquaporins c.Many aquaporins are found in the kidneys, eyes, lungs, salivary glands, and the braindoc 3.Requirements of Osmosis a.There must be a solute concentration difference on either side of a membrane permeable to water. b.The membrane must be impermeable to the solute, or the concentration difference will not be maintained. Solutes that cannot cross and permit osmosis are called osmotically active. 4.Water Movement in Osmosis a.The net movement of water is from the side with more water (more dilute) to the side with less water (less dilute). b.However, when osmosis is discussed, we say that water moves from the area of low solute concentration to the area of high solute concentration. (water moves toward the side with the higher solute concentration) 5.Osmotic Pressure a.Osmotic pressure is the force surrounding a cell required to stop osmosis. b.Can be used to describe the osmotic pull of a solution. A higher solute concentration would require a higher osmotic pressure. Pure water has an osmotic pressure of zero. doc 6.Molarity and Molality a.Moles 1)A mole of a compound can be measured as its molecular weight in grams. 2)The number of atoms in 1 mole is always the same no matter the substance:6.02 X 1023 particles 3)You can make molar solutions (1M) or molal solutions (1m).doc b.Molarity - Moles Solute/Liter Solution 1)Glucose has a mol. wt. of 180. For a 1 molar solution of glucose, dissolve 180 g glucose in water to make 1 L solution. 2)NaCl has a mol wt of 58.5. For a 1 molar solution of NaCl, dissolve 58.5 g NaCl in water to make 1 L solution. 3)Not useful for a discussion of osmosis, since the solute concentration is different depending on the solute. More water is used to make the 1 molar solution of NaCl. c.Molality - Moles Solute/Liter Solvent 1)1 molal solutions take the mol wt in grams dissolved in exactly 1 L water. 2)The amount of water never changes, so you can compare solute concentrations to predict the direction of osmosis. 3)Does not depend on the chemistry of the solute, but on how many particles are present in the solution 7.Osmolality a.Osmolality is the total molality of a solution when you combine all of the molecules within it. b.A 360 g (2m) glucose solution would have the same osmolality as 180 g glucose (1m) + 180 g fructose (1m) solution. c.These are both 2 Osm solutions. d. Electrolytes that dissociate in water have to be assessed differently. They have a dissociation factor. 1)NaCl dissociates into Na+ and Cl- in water and must be counted as separate particles.NaCl à Na+(aq) + Cl-(aq) 2)A 1m NaCl solution would actually be a 2 Osm solution. 8.Tonicity a.Tonicity is the effect of a solute concentration on the osmosis of water.If a membrane separates a 0.3m glucose solution and a 0.15m NaCl solution, there will be no net movement of water = isotonic. b. Tonicity takes into account the permeability (penetrating or non-penetrating nature) of the membrane to the solutes. If the solutes can cross the membrane, the tonicity will change. -The fate of red blood cells in isotonic, hypotonic, and hypertonic solutions -Isotonic solutions include 0.3m glucose or a 0.15m NaCl solution. 5% Dextrose solution, 0.9% NaCl or normal saline, both are isotonic.doc
Levels of organization
Atom: Carbon Molecule: Carbon Dioxide Cell: Stomach Cell Tissue: Epithelial Tissue Organ :Stomach Organ System: Digestive System Organism: YOU smaller than a cell: atom and molecule larger than a cell: tissue, organ, organ system, organism doc
Active Versus Passive Transport
Body fluids are solutions of water and dissolved solutes (ions, glucose, amino acids, etc.) that surround our cells. The plasma membrane is a selectively permeable barrier that allows some ions and molecules to pass through but prevents the passage of many molecules. The passage of some of these molecules through the semipermeable plasma membrane is essential for life. Active transport and passive transport are two mechanisms responsible for moving these necessary substances across the plasma membrane.
Jaw muscle contraction (masseter spasm) is one of the key physical findings seen in David's case of malignant hyperthermia. Explain how calcium functions to cause contraction of a skeletal muscle cell.
Calcium is released from the sarcoplasmic reticulum and bound to troponin on actin filaments. This binding allows myosin heads to form a cross-bridge because tropomyosin has been displaced, which ultimately results in contraction.
Grading
Changes in the strength of muscle contraction or the extent of contraction in proportion to the load on the muscle. Grading is responsible for the smooth movements like swimming, walking etc..
Predict at least three factors that could account for the difference between the individual with the fastest average reaction time and the individual with the slowest average reaction time in your group. (What factors can increase or decrease reaction time?)
Computer sensitivity Muscle memory for clicking (video games) Amount of distractions
Fluorescence labeling of cells and tissues
Fluorescence labeling allows for the detection of the presence of certain molecules and measures the number of molecules in that specific sample. When fluorescent dyes absorb light, it raises their energy to an excited state. Then as they come down from this excited state, they emit the fluorescent light we can detect
Glycemic Load
Glycemic Load (GL) takes into account both quality and quantity of carbohydrates in food. GLFood = (GIFood x amount (g) of available carbohydrateFood per serving)/100 For a typical serving of a food, GL would be considered high if GL≥20, intermediate if GL is11-19, and low if GL≤10. Dietary GL is the sum of the GLs for all foods consumed in the diet. Example: Mean GI of watermelon is 76, same as that of a doughnut, but one serving of watermelon provides 11g of available carbohydrate, while a medium doughnut has 23g of available carbohydrate. One serving of watermelon has a GL of 8, while a medium-sized doughnut has a GL of 17.
Negative feedback loops contain three functional components that are necessary for regulating a variable (note that in this case the variable is not considered a functional component of the loop).
Variable-room temp, blood pressure-item/value/variable that the loop controls sensor (receptor)-thermometer, pressure receptors-detects the change or the stimuli integrator-thermostat, brainstem-processes received stimuli, compares it to the set point, and determines an appropriate response effector-furnace, heart,-carries out the change to return to the set point value
Western blot
Western Blot is a protein analysis using protein denaturation followed by gel electrophoresis to detect specific proteins from a sample of extract or tissue. Gel electrophoresis allows for the mixture of proteins to be separated based on molecular weight to then discover what they are. The purpose is to find out the size of the protein of interest and measure the amount of protein expression.
Choose one stimulus from Q. 3, and describe in a complete sentence how the stimulus would travel to the central nervous system (CNS).
When you see something, the retina (as receptor) receives the stimulus and relays it to the occipital lobe (integrating center) via action potentials where the sight stimulus is processed and then the signals are sent via the optic nerve to other parts of the brain allowing the full processing of the image.
Is it possible to have a medical term with multiple roots?
Yes- electrocardiogram
Which tissue or organs produce hormones?
adrenal gland, thyroid gland, testes, ovaries, endocrine glands
What is an endocrine gland and how is it different from an exocrine gland?
an endocrine gland is a ductless gland and an exocrine gland has ducts.
Levels of Organization
atoms molecules cells tissues organs organ systems organisms population of one species ecosystem of different species biosphere doc
In addition to blood pressure, what other variables in the human body are controlled by homeostatic feedback loops? List two examples:
blood glucose levels and body temperature
What are two examples from the list above that can be found inside a cell?
carbon and carbon dioxide
Concept Map to Understand the principles of Endocrine Regulation
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Cortex silver stain high power
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Diagnosing Diabetes: Oral Glucose Tolerance Test
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Hypothalamus is the Master Regulatory Tissue
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Neuron : Functional Unit of the Nervous System
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Neuron: The functional Unit of the Nervous System
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Pituitary Gland
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Reaction Versus Reflex
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Spinal cord, low power
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adrenal gland
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adrenal gland histology
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Name the two divisions of the peripheral nervous system (PNS), and give the primary function of each.
he Sensory Division and the Motor Division
If blood pressure is too low,
low profusion (low oxygen transport to the tissues) and the brain would normally tell the heart to beat faster to compensate for the change.
insula lobe
memory; sensory (principally pain) and visceral integration
What gland in the brain is a major organizing center of hormone release?
pituitary gland
active transport
the high concentration would be on the bottom of the diagram how do solutes move along their concentration gradient? They move against the gradient (low to high) active transport moves solutes _up_ a concentration gradient. Active transport processes use ATP because energy is required to move substances against their concentration gradient.
Epidemiological Studies
•Prospective vs. Retrospective studies -Enrolls and follows a group of individuals (cohort) over time -Looks backwards at a cohort, often to identify risk factors •Case-Control -Matches sick population with healthy controls •Longitudinal studies vs. Cross-sectional studies -Individuals repeatedly sampled over time -Study conducted at a single point in time •Meta-analysis -Is a quantitative approach to reviewing literature in a specific area. Integrates data from related studies; attempts to resolve differences. -Often correlative, not mechanistic
Experimental Physiology
A branch of physiology where the various body functions are studied in a laboratory setting commonly with animals but sometimes with human subjects.
Cranial Nerves
1.Part of the PNS 2.Nerves that arise directly from nuclei in the brain 3.Twelve pairs 4.Most are mixed nerves with both sensory and motor neurons (somatic and parasympathetic) 5.Those associated with vision, olfaction, and hearing are sensory only and have their cell bodies in ganglia located near the sensory organ.
Electromyography
The detection, amplification, and recording of changes in skin voltage produced by underlying skeletal muscle contraction is electromyography. Motor unit activation causes muscle fibers to generate and conduct electrical impulses resulting in contraction of the muscle fibers. Many fibers simultaneously conducting electrical signals induce voltage differences that can be measured by surface electrodes.
Is the goal of a homeostatic feedback loop to maintain a regulated variable at a constant value?
The goal would be to maintain the variable in question around a constant value or particular set point. For example, blood pH must be maintained between values of 7.35 and 7.45 in order for it to be compatible with life. One set value is not necessary but to cannot exceed certain limitations or boundaries.
diffusion through the plasma membrane
1.Small, nonpolar (or uncharged) lipid-soluble molecules pass easily through the lipid portion of the membrane. Examples: O2, CO2, and steroid hormones 2.Gas exchange: net diffusion of O2 into cells and CO2 out of cells due to concentration gradients. (Opposite in lungs.) 3.Water can pass through using special channels called aquaporins in a process called osmosis
Cerebral Cortex
1.The outer region of the cerebrum composed of 2 to 4 mm gray matter with underlying white matter. 2.Characterized by raised folds called gyri separated by depressed grooves called sulci; together called convolutions 3.Each hemisphere is divided by deep sulci or fissures into 4 lobes - Frontal, Parietal, Temporal, Occipital 4.Frontal and Parietal Lobes a.Separated by the central sulcus b.The precentral gyrus is located in the frontal lobe and is responsible for motor control; neurons called upper motor neurons c.The postcentral gyrus is in the parietal lobe and is responsible for somatesthetic sensation (coming from receptors in the skin, muscles, tendons, and joints); called the somatosensory cortex 5.Temporal, and Occipital Lobes a.Temporal lobe: auditory centers b.Occipital lobe: vision and coordination of eye movements c.Insula: encoding of memory and integration of sensory information with visceral responses; receives olfactory, gustatory, auditory, and pain information doc
Experimental Objectives reaction time
1.To become familiar with the procedures for recording the galvanic skin response 2.To observe and record changes in respiratory rate, heart rate, and skin resistance associated with somatic and special sensory stimuli. 3.To observe and record changes in respiratory rate, heart rate, and skin resistance associated with cognitive behavior and emotion. 4.To analyze a 3-channel polygram recorded under various experimental conditions to gain a better understanding of polygraphy and its potential for use and misuse. objectives: 1.Formulate a hypothesis regarding reaction times under various conditions 2.Test the hypothesis by making observations, compiling the results and drawing conclusions regarding the hypotheses.
Reflex Arc
1.Unconscious motor response to a sensory stimulus 2.Parts of an arc a.Sensory receptor b.Sensory neuron c.Association neuron in CNS d.Motor neuron e.Effector - muscle or gland that responds 3.Types of arcs a.Somatic reflex - effectors are skeletal muscles b.Autonomic reflex - effectors are smooth muscle, cardiac muscle, or glands doc
etymology
A) Cardiology: discipline of study pertaining to the heart B) Bradycardia: state of a slow heart C) Myocyte: muscle cell A) The study of diseases- pathology B) An irregular, fast heart rate- tachycardia A) Myocyte O is the connecting vowel B) cardiology I is the connecting vowel C) cardiomyocyte I and O are connecting vowels A) cardiology - "cardio" means heart. B) Pulmonologist- "pulmo" means lung C) Uerologist- "uero" means urine D) Neurologist- "Nuero" means nerve *Electroencephalogra*phy: detecting and displaying electric activity in the brain *Pneumonoultramicroscopi*csilicovolcano*con*iosis: lung illness caused by small particles in the lungs, possibly caused by dust from volcanic eruptions
What are some other diseases that may be related to MS?
Acute Disseminated Encephalomyelitis (ADEM), Balo's disease, HTLV-I Associated Myelopathy (HAM), Neuromyelitis Optica (NMO), Schilder's Disease, Transverse Myelitis.
Animal Studies
Advantages: -Short gestation -Short lifespan -Genetic manipulations -introduce human disease gene -knock-in, knock-out, transgenic -Many conserved genes -Tightly controlled conditions Disadvantages: -Not human -Difficult to assess 'human' traits, i.e. cognition and emotion -Don't spontaneously develop human diseases -Species specific isoforms -Inbreeding
Define digital health technology.
Digital health technology are electronic tools, systems, and devices that measure the data of the health of an individual or many people.
Skeletal Muscle Structure
Each skeletal muscle contains numerous muscle fibers -Each muscle fiber encloses a bundle of 4 to 20 elongated structures called myofibrils -Each myofibril in turn is composed of thick and thin myofilaments doc
homeostasis
Homeostasis refers to a process of dynamic constancy that regulates internal environments around a particular set point consistent/compatible with life regardless of external conditions, utilizes energy and typically occurs through self-limiting negative feedback loops
Metabolic Syndrome Links Diabetes and Cardiovascular Disease
Metabolic syndrome is a group of risk factors that occur together and increase the risk for coronary artery disease, stroke, and type 2 diabetes. It is becoming increasingly common in the US. Metabolic syndrome : Three out of the following five criteria -Visceral obesity - blood pressure ≥ 130/85 - fasting plasma glucose ≥ 110 mg/dL -Elevated fasting plasma triglycerides - low plasma HDL-C levels
Is it possible to have a medical term without a root?
No, it is not possible, unless you consider a "cough" or "cold" as medical terminology.
Northern Blot
Northern Blot is an RNA analysis using gel electrophoresis to detect specific RNA fragments from a sample of extract or tissue. The purpose is to measure the RNA expression of particular genes.
Basic Steps of Scientific Method
Observation (and/or study of prior knowledge)-> Hypothesis-> Experimentation-> Collection and analysis of data (can you replicate results?)-> Conclusion: reject or accept (-> theory) hypothesis
osmosis pogil
Osmosis is the diffusion of water through a semipermeable membrane to maintain equilibrium of solutes on both sides of the membrane. A solute imbalance causes water to move across the plasma membrane. The saying goes, "Water follows salt (solute)." a) How does water move relative to its own concentration gradient? Water moves down it's own concentration gradient b)How does water move relative to the solute concentration gradient? Water moves up relative to the solute concentration gradient (to where there is more salt) What causes an imbalance in water concentration or solute concentration that leads to osmosis? A change in the external environment (hyper, hypo, or isotonic solution) or change in water levels outside the cell Osmosis is the diffusion of water through a semipermeable membrane to maintain equilibrium of solutes on both sides of the membrane.
3 Types of Muscle
Primary function of muscle: Conversion of chemical energy into mechanical energy •Skeletal -"Voluntary"; striated, attached to the skeleton -Locomotion, heat -Contracts in response to somatic motor neuron only •Cardiac -Involuntary; striated -Only in heart -Autonomic control -Endocrine modulation •Smooth -Involuntary; no striations -Internal organs: stomach, bladder, blood vessels -Autonomic control -Endocrine modulation doc
Use the completed table and the autopsy data provided below for each of the 'virtual rats' in this experiment to help you determine which of the rats was treated with which of the four hormones (TRH, TSH, ACTH, or Cortisol). Except for the control, each rat was treated with only one hormone. Use the values obtained for the control rat as a comparison. To be considered significant, any change observed between the control rat and the experimental rat should be >20% or more. If a change is less than 20%, it is attributed to normal biological differences between individuals or to errors in measurement due to calibration limitations of the measuring equipment.
Rat 1 was most likely treated with: ACTH Pituitary: 10.1 mg decrease from control Thyroid: 245 mg same from control Thymus: 250 mg decrease from control Adrenals: 100 mg increase from control Body weight: 200 g decrease from control Rat 2 was most likely treated with: TRH Pituitary: 25 mg increase from control Thyroid: 490 mg increase from control Thymus: 462 mg same from control Adrenals: 39 mg same from control Body weight: 160 g decrease from control Rat 3 was most likely treated with: cortisol Pituitary: 9.8mg decrease from control Thyroid: 245 mg same from control Thymus: 150 mg decrease from control Adrenals: 30 mg decrease from control Body weight: 150 g decrease from control Rat 4 was most likely treated with: TSH Pituitary: 8 mg decrease from control Thyroid: 500 mg increase from control Thymus: 455 mg same from control Adrenals: 37 mg same from control Body weight: 152 g decrease from control
Hypothalamus and Pituitary Gland
Regulation of the Pituitary Gland 1)ADH and oxytocin are transported along the hypothalamo-hypophyseal tract to the posterior pituitary gland, where they are stored until needed. 2)The hypothalamus also produces releasing hormones and inhibiting hormones that are transported along the hypothalamo-hypophyseal portal system to regulate the secretion of pituitary hormones.
What are the 'scleroses' in Multiple Sclerosis and where do they occur? How does this influence nerve transmission?
Scleroses are scars present on the myelin sheaths of the neurons axons of the brain and the spinal cord. Multiple sclerosis is an autoimmune disease that results in the damaging or destruction of the myelin sheath along the neurons, in a process called demyelination. Messages that travel along a demyelinated axon are often delayed or blocked
SUMMARY atoms-biosphere
Sequence DNA Quantify RNA Quantify Protein Localize RNA Localize Protein Cell Culture (in vitro) DNA Cloning Overexpression Knock-down Animal models Transgenic Animals Human subjects Population Studies
Why did steroids help alleviate Molly's symptoms?
Steroids help relieve MS flares because they reduce the nerve inflammation that is caused by a flare. Steroids can help relieve the effect and severity of Molly's symptoms and alleviate symptoms such as balance issues, difficulty breathing, severe muscle spasms and cramps, severe weakness, and visual disturbances.
History of Physiology : Ancient times
Susruta : 600 BC - 200 AD. "Susruta Samhita Hippocrates : Before 350 BC. "The Nature of Man" Aristotle : (384 - 322 BC). Correlation between structure and function. Galen : c. 130-200 AD Led to a lot of misconceptions.
1.Provide an overview of the various parts of the nervous system. Include CNS, PNS, Afferent and efferent pathways, and any other relevant details.
The CNS includes the brain and spinal cord, while the PNS includes nerves, and carries sensory information to the CNS, and through nerves away to various parts of the body. The afferent pathway involves the sensory neurons that bring information to the CNS. The efferent pathway carries information from the CNS to muscles and glands and is made up of the somatic and autonomic nervous systems. Somatic controls voluntary skeletal muscles and autonomic controls smooth muscle, cardiac muscle, glands and involuntary movement, and is crucial for maintaining homeostasis. The autonomic is made up of the sympathetic division (fight or flight) and the parasympathetic division (rest or digest).
Describe in 1-2 complete sentences how the motor commands from the CNS would travel to the effector target organ or tissue. Tell if the motor command will travel via the somatic or autonomic nervous system; explain why.
The CNS is the integrating center which contains the brain and spinal cord and through action potentials sends information to the effector organ or tissue. A motor command would travel through the somatic motor system if the effector organ or tissue is under voluntary control, such as skeletal muscle. It would travel through the autonomic nervous system if the effector organ or tissue is under involuntary control, such as smooth and cardiac muscle.
A patient was in a serious accident that caused a lot of blood loss. In an attempt to replenish body fluids, a volume of distilled water with a pH of 7.0 equal to that of the blood lost is transferred directly into the patients' veins. What will be the most probable impact on the persons red blood cells from this transfusion?
The distilled water can be considered a hypotonic solution, so water would enter the cells of the patient.
Which of your body structures was the sensory receptor in the reaction time test? What was the stimulus?
The eyes were the sensory receptors and the green color on the screen was the stimulus.
Glycemic Index
The glycemic index (GI) is a ranking of carbohydrates on a scale from 0 to 100 according to the extent to which they raise blood sugar levels after eating. High GI Foods : Rapidly digested and absorbed, causing fluctuations in blood glucose levels. Low GI Foods : Slow digestion and absorption, resulting in gradual increases in blood glucose and insulin levels. Low GI foods can help reduce the incidences of coronary heart disease, diabetes and obesity.
Which of your body structures was the effector in the reaction time test? What was your motor response?
The muscle in our finger to click on the mousepad was the effector. The motor response was clicking.
Electromyogram
The reading obtained from electromyography.
How many sarcomeres do you think are in a muscle cell found in your quadriceps?
Thousands of sarcomeres are found in a muscle cell of my quadriceps.
Is tonicity due to a solution containing a permeable or impermeable solute?
Tonicity depends on the impermeable solute. An impermeable solute cannot cross and therefore cannot establish equilibrium, so the water must be what establishes the equilibrium by moving into or out of the cell.
frontal lobe
Voluntary motor control of skeletal muscles; personality; higher intellectual processes (for example, concentration, planning, and decision making); verbal communication
What happens when a negative feedback loop is damaged or interrupted?
When a negative feedback loop is damaged or interrupted the stimuli cannot be corrected for by the loop, thus allowing the change to impact the body. Homeostasis cannot be maintained thus leading to conditions inconsistent with the life of the organism in question that can lead to disease or death. With regard to blood pressure, if the value is too low, then the body will receive insufficient quantities of oxygen and the person will pass out and potentially die if not corrected.
transport
Which process(es) involve transport directly through the phospholipid membrane? Simple diffusion Which process(es) require protein channel/carrier for transport? Facilitated diffusion and active transport Are solutes transported by simple diffusion permeable or impermeable to the plasma membrane? Permeable Are solutes transported by facilitated diffusion permeable or impermeable to the plasma membrane? Impermeable
Malignant hyperthermia causes a hypermetabolic state in skeletal muscle, which is triggered by high demands for ATP during uncontrolled muscle contractions.
a. What is the role of ATP in cross bridge cycling? In cross bridge cycling ATP binds to myosin, moves it to a high energy state, and removes it from the actin active site. The attachment of ATP to the myosin allows the cross bridge to form. b. What is the role of ATP in generating a resting membrane potential? The potassium/sodium ATPase pump generates a resting membrane potential. c. What is the role of ATP in maintaining calcium concentration gradients? ATP maintains calcium concentration gradients by reabsorbing calcium into the sarcoplasmic reticulum
Cellular Effects of Insulin
- Constantly recycled transporters; insulin maintains the cycle and GLUT4 transporter numbers are high in the plasma membrane - In many T2DM patients the response of pancreatic beta cells to glucose is impaired
diagnosis of diabetes mellitus
-classic symptoms of diabetes mellitus (polyuria, polydipsia, polyphagia, and weight loss and random plasma glucose greater than/equal to 200 mg/dL -fasting plasma glucose greater than 126 mg.dL -two hour post glucose load (75g) plasma glucose greater than 200 mg/dL, and confirmed by repeat test fasting: no caloric intake for at least 8 hr plasma glucose obtained in a sodium fluroide (gray top) tube
What are the Types of Hormones?
1. Amines, derived from tyrosine and tryptophan: Behave similar to steroid hormones Examples: hormones from the adrenal medulla, thyroid, and pineal glands 2. Polypeptides and proteins: Majority of hormones. Polar, cannot diffuse into cells. Examples: antidiuretic hormone, insulin, and growth hormone 3.Steroid hormones are lipids derived from cholesterol. Can diffuse through the plasma membrane and enter target cells a.Examples: testosterone, estradiol, progesterone, cortisol, aldosterone
plasma membrane transport
1. Plasma membrane permeability a.The plasma membrane is selectively permeable, meaning that it allows some materials to cross but not others. b.Generally not permeable to proteins, nucleic acids, or other large molecules c.Generally permeable to ions, nutrients, and wastes 2. Categories of Membrane Transport a.non carrier-mediated -simple diffusion of lipid-soluble molecules -simple diffusion of ions through nonspecific channels -simple diffusion of water= osmosis b. carrier-mediated -facilitated diffusion -active transport 3. energy involvement in membrane transport a. passive transport: molecules move from higher to lower conc without using metabolic energy b. active transport: molecules move from lower to higher conc using ATP and specific carrier pumps doc
body fluids
1.67% of our water is within cells in the intracellular compartment. 2.33% is in the extracellular compartment. Of this: a.20% is in blood plasma. b.80% makes up what is called tissue fluid, or interstitial fluid; connects the intracellular compartment with the blood plasma.
Ascending and Descending Tracts
1.Ascending tracts convey sensory information from cutaneous receptors, proprioceptors, and visceral receptors. 2.Most of the sensory information from the right side of the body crosses over to the left side of the brain. Similarly, information from the left side of the body arrives at the right side of the brain. This process, known as decussation, can happen in the spinal cord or in the medulla. 3.The descending fibers can be corticospinal, or pyramidal and the extrapyramidal tracts. 4.Corticospinal or pyramidal tracts are the main way for the left hemisphere to control the right side of the body and vice versa. 5.The extrapyramidal pathways originate in the brain stem and are controlled by structures in the brain that regulate motor circuits. Parkinson's disease symptoms referred to as extrapyramidal.
Spinal Cord
1.Connection between the brain and the body. 2.Sensory information from most of the body is communicated to the brain via the ascending tracts of the spinal cord 3.Motor signals from the brain are directed to the rest of the body via descending tracts of the spinal cord. 4.Protected by the vertebral column. 5.Spinal cord starts at the foramen magnum of the skull and extends until the first lumbar vertebra.
Regulation of Blood Osmolality
1.Constant osmolality must be maintained, or neurons will be damaged. 2.Osmoreceptors in the hypothalamus detect increases in osmolality (due to dehydration). This triggers: a.Thirst b.Decreased excretion of water in urine through release of antidiuretic hormone (ADH) which is also known as vasopressin. 3.With a lower plasma osmolality, osmoreceptors are not stimulated, so more water is excreted in urine. doc
extracellular matrix
1.Contains protein fibers of collagen and elastin, and a gel-like ground substance. a.Protein fibers provide structural support. b.Ground substance is composed of glycoproteins (composed of proteins and sugars) and proteoglycans (composed of polysaccharides). c.Integrins are glycoproteins that extend from the cell cytoskeleton and bind to the extracellular matrix. 2.Functions of Integrins a.Impart polarity to cells b.Affect adhesion and motility c.Affect proliferation
Brain
1.Gray matter forms the cortex and deep nuclei; white matter is deep forming tracts 2.The adult brain has 100 billion neurons. 3.It weighs about 1.5 kg (3 to 3.5 pounds). 4.It receives 15% of the total blood flow to the body per minute. 5.Scientists have demonstrated neurogenesis (the formation of new brain cells from neural stem cells) in adult brains within the hippocampus and the lateral ventricles
Hypothalamus
1.Hypothalamus a.Very important for maintaining homeostasis and regulating the autonomic system. Contains centers for: 1)Hunger/satiety and thirst 2)Regulation of body temperature 3)Regulation of sleep and wakefulness 4)Sexual arousal and performance 5)Emotions of fear, anger, pain, and pleasure 6)Control of the endocrine system 7)Controls hormone secretion from the pituitary gland
carrier-mediated transport
1.Large or polar molecules cannot diffuse through the membrane. E.g.: amino acids, glucose, and other organic molecules. 2.Carrier proteins within the plasma membrane move these molecules across. 3.Characteristics of the carriers a.They are specific to a given molecule. b.There may be competition for similar carriers or molecules. c.Saturation - number of carriers is limited 4. Transport rates increase with increased molecule concentration until saturation is met; this is the transport maximum (Tm) where all carriers are in use. doc
Cerebrum
1.Largest portion of the brain - 80% of the mass 2.Responsible for higher mental functions 3.Consists of a right and left cerebral hemisphere connected internally by the corpus callosum doc
Basal Nuclei
1.Masses of gray matter located deep in the white matter of the cerebrum 2.Degeneration of dopaminergic neurons from the substantia nigra to the corpus striatum causes Parkinson's disease 3.Involved in maintaining the balance between excitatory and inhibitory motor circuits doc
Measuring Glycemic Index
1.Measured amounts of food with 10 - 50 grams of carbohydrates are fed to 10 healthy volunteers after an overnight fast. 2.Finger-prick blood glucose measurements are taken every 15 - 30 minutes. 3.A blood sugar response curve is plotted and the area under the curve (AUC) is calculated to reflect the total amount of rise in blood glucose levels. 4.GI rating (%) is calculated by dividing the AUC of test food by AUC of same amount of glucose.
rate of diffusion
1.Measured by the number of diffusing particles per unit of time 2.Depends on: a.Magnitude of concentration difference - the driving force for diffusion b.Permeability of the membrane to the molecules c.Temperature of the solution; higher temperature increases the rate d.Surface area of the membrane; increased by microvilli
Spinal Nerves
1.Part of the PNS 2.Nerves that arise directly from the spinal cord 3.31 pairs: 8 cervical, 12 thoracic, 5 lumbar, 5 sacral, 1 coccygeal 4.All are mixed nerves that separate near the spinal cord into a dorsal root carrying sensory fibers and a ventral root carrying motor fibers. a.The dorsal root ganglion houses the sensory neuron cell bodies. b.Motor neuron cell bodies are in the ventral gray horns
Diencephalon
1.Part of the forebrain that includes the epithalamus, thalamus, hypothalamus, part of the pituitary gland, and the third ventricle 2.Surrounded by the cerebral hemispheres doc
Diffusion and Osmosis
1.Solution: consists of a solvent (water) and a solute (molecules dissolved in water) a.Molecules in a solution are in a constant state of motion. b.If there is a concentration difference between two regions, random motion will establish equilibrium via diffusion. c.Obeys the 2nd Law of Thermodynamics - diffusion increases entropy 2.Diffusion will occur without a physical separation or across a permeable membrane. 3.Net diffusion - due to random movement, the net direction of diffusion is from high to low solute concentration. 4.Mean diffusion time - the average time it takes for a solute to diffuse. a.Increases with the square of the distance the solute must travel (less distance, faster) b.Distances beyond 100 µm, diffusion time is too long to be effective doc
Thalamus and Epithalamus
1.Thalamus a.Paired masses of gray matter b.Relay center through which all sensory information, except smell, is passed to the cerebrum c.Considered to be important for focus and concentration 2.Epithalamus a.Contains the choroid plexus over the third ventricle where cerebrospinal fluid is produced b.Also contains the pineal gland, which secretes the hormone melatonin that helps regulate circadian rhythms
extracellular environment
1.The extracellular environment includes everything located outside the cells. 2.Cells receive nourishment from and release wastes into the extracellular environment. 3.Cells communicate with each other by secreting chemical regulators into the extracellular environment. doc
What is the total number of people that have been infected worldwide with SARS-CoV2 so far and how many have died from it? (Report the data with the date)
109 million have been infected worldwide with SARs-CoV2 so far. 2.41 million worldwide have died from it so far. (02-16-2021).
try to name 3 organs that are shared by two or more body systems, and identify those body systems.
1: Organ: Penis What two systems? Excretory and Reproductive 2: Organ: Spine What two systems? Skeletal and Nervous 3: Organ: Throat What two systems? Digestive and Respiratory
What is the total number of people that have been infected in the US with SARS-CoV2 so far and how many have died from it? (Report the data with the date)
27.7 million have been infected in the US so far and 486K have died from it in the US. (02-16-2021).
bands
A band- stacked thick and thin myofilaments: extends the length of the thick filament including a portion of the thin filament, dark bands, I band- consists only of thin myofilaments, light bands, divided into two halves by a disc of protein called the Z line, area between the ends of thick filaments. H zone- center of the A band, consisting of thick bands only, area between the ends of thin filaments Z disc- disc of protein, vertical line at each end of sarcomere that divides I bands into two halves M line- is the attachment site for thick filaments and is in the center of the A band (center of the sarcomere
Skeletal Muscle Structure bands
A bands = Stacked thick & thin myofilaments -Dark bands H bands = Center of the A band, consisting of thick bands only I bands = Consist only of thin myofilaments -Light bands -Divided into two halves by a disc of protein called the Z line Sarcomere = Distance between two Z lines -Smallest subunit of muscle contraction
Galvanic skin response- basic principles
A change in the emotional state of a person often results in a change in autonomic responses occurring in skin and subcutaneous tissues. This is due to the sympathetic branch of the autonomic nervous system Ohm's Law states that I (Amps) = E (volts) / R (Ohms) It is possible to measure the bioelectrical response of the human skin. Galvanic Skin Resistance : When a weak electric current is applied to electrodes placed about an inch apart on the skin, and the electrical resistance (Galvanic skin resistance) between them is measured, it varies with the emotional state of the subject. Galvanic Skin Potential : When the voltage between the two electrodes placed on the skin (Galvanic skin potential) is measured without any current being applied, it will vary with the emotional state of the subject. The combined changes in Galvanic skin resistance and Galvanic skin potential is called the Galvanic Skin Response (GSR).
feedback system
A feedback system involves the reception or detection of a stimuli that triggers a feedback response to bring the system as a whole back to the set point value.
Microarray
A microarray is used to detect the variation and expression of many genes. DNA microarrays are bound to glass chips. DNA molecules attached to each chip is like a probe used to detect gene expression. The DNA molecules are compared to a normal DNA sample to see what is missing or extra
electromyography- time to fatigue
A motor neuron and all of the skeletal muscle fibers that it stimulates to contract is called a motor unit. Each muscle has many motor units. These can vary in number from only a few muscle fibers to several hundred muscle fibers. Motor unit recruitment is the addition of motor units to increase the overall contraction strength of a muscle. Electromyography (EMG) measures the number and frequency of motor units active in a muscle. An electromyogram (EMG) is the recording of the voltage produced by skeletal muscle contraction and is a measure of the active motor units in a muscle. As contraction strength decreases so does the electrical activity recorded by the EMG. As a skeletal muscle contracts, either continuously or repeatedly, the chemical environment inside the muscle fibers begins to become less favorable for contraction. This leads to a weakening of the muscle contraction called muscle fatigue. The exact mechanism of the phenomenon is not known. In this simulation, you will squeeze with 100% grip strength clench and maintain full force as long as possible. You will measure the force and number of active motor units. The purpose of this experiment is to examine muscle fatigue. Time to fatigue is defined as the amount of time it takes for a muscle contraction to decrease to 50% maximum strength. Both force and motor unit recruitment will decrease over time while maintaining maximum grip strength. I will start with maximum grip strength and hold it as long as possible while measuring the force and the number of motor units that are active at regular intervals. Force decreases over time due to a decrease in motor units
Skeletal Muscle
A motor unit consists of a motor neuron and all of the muscle fibers it innervates -All fibers contract together when the motor neuron produces impulses Muscles that require precise control have smaller motor units Muscles that require less precise control but exert more force, have larger motor units Recruitment is the cumulative increase in motor unit number and size leading to a stronger contraction doc
graded potential and action potential
A multipolar neuron is composed of a cell body, an axon, and hundreds of dendrites. Each neuron receives numerous inputs at the receptive region, which includes both the dendrites and cell body. Neurons send signals down the axon toward the synaptic knob. Resting neurons require a membrane potential in order to send or receive electrical signals. A typical neuronal resting membrane potential is -70 mV, indicating that the inside of the plasma membrane is more negative relative to the outside. The resting membrane potential is established by the Na+/K+ pump and by the sodium and potassium leakage channels. The leakage channels allow for ions to diffuse down their electrochemical gradients, while the Na+/K+ pump moves ions against their gradients. The Na+/K+ pump establishes the K+ and Na+ gradients, which drive the diffusion of these ions through leakage channels. Although both Na+ and K+ diffusion play a role in establishing the resting membrane potential, potassium diffusion is more important. Normally, sodium and potassium leakage channels differ because sodium ions diffuse through leakage channels into the cell, but potassium ions diffuse through leakage channels out of the cell A resting membrane potential of -70 mV indicates that the charges lining the inside of the plasma membrane are negative compared to the charges lining the outside Changes of the membrane potential are necessary for electrical signals to be carried along a neuron's membrane. Within the receptive region, neurotransmitters bind to specific membrane receptors triggering the opening of ligand-gated ion channels. This results in the production of localized graded potentials called postsynaptic potentials, which alter the membrane potential. Postsynaptic potentials spread multidirectionally along the membrane and decrease in strength with time and distance. Graded potentials are produced within the receptive segment of a neuron Graded potentials result from the opening of ligand-gated channels An inhibitory postsynaptic potential results from the opening of potassium and/or chloride channel excitatory postsynaptic potential: doc Summation is the cumulative effect of multiple excitatory and inhibitory postsynaptic potentials (PSPs) that converge in the dendrites and cell body of the postsynaptic neuron. If these PSPs cause the initial segment (also called the axon hillock) to depolarize to threshold, then an action potential occurs. Since an action potential is an all-or-none event, any subthreshold depolarizing stimuli do not result in the development of an action potential. Likewise, once threshold has been met, further depolarization has no effect on the action potential. Indicate the summative effect that brings the initial segment closest to threshold -Two EPSPs in proximity to each other
Skeletal Muscle Contraction
A muscle contracts and shortens because the myofibrils contract and shorten -Myofilaments themselves do not shorten -Instead, the thick and thin filaments slide relative to each other -Sliding filament mechanism -Z lines move closer together, as the I and H bands become shorter -A band does not change in size doc
Define a 'prospective observational cohort study. Describe the study design. How long was the study and how many subjects participated? What was the compliance rate?
A prospective observation cohort study observes a group of people after being exposed to a certain factor in order to investigate the outcome. Two hundred and ninety-seven participants were enrolled between April 29th and September 29th, 2020. The medium duration of follow-up was 42 days (range 0-152 days). A median of 28 HRV samples (range 1-129) were obtained per participant. Study compliance over the follow-up period was 70.4%.
Osmosis: movement of water
A selectively permeable (semipermeable) membrane only allows certain molecules through and blocks others. Osmotic pressure is influenced by changes in nonpermeable solute concentration. Higher nonpermeable solute concentration increases the amount of water that will cross the membrane. You will place different solutions in thistle tubes and beakers, and then record changes in the volume of water moved by osmosis -more water is drawn up into the thistle tube with higher concentrations of corn syrup
Motor Unit
A single motor neuron and all of the muscle fibers it controls is a motor unit. Motor unit recruitment: The increase in the number of simultaneously active motor units within a muscle based on demand. Control of skeletal muscle contraction - the number of motor units within a muscle that are activated - the frequency of motor neuron impulses in each motor unit doc
How so an MRI and spinal tap help confirm the diagnosis of Multiple Sclerosis?
A spinal tap helps confirm the diagnosis of MS because it shows if the amount of protein, white blood cells, and myelin in the spinal fluid is too high. An MRI can detect the scars used by MS which are known as lesions.
Dead language
A) What is a "dead" language? Historical evidence about a language that existed, but no one can speak it anymore B) Why is "modern" medical terminology based on "dead" languages? Despite the different meaning of modern words, using roots of dead languages suggests the overall meaning of a word
Skeletal Muscle Contraction thick and thin
A thick filament is composed of several myosin subunits packed together -Myosin consists of two polypeptide chains wrapped around each other -Each chain ends with a globular head A thin filament is composed of two chains of actin proteins twisted together in a helix doc
Diagnosing Diabetes
A1C: Measure of glycated Hb in blood; measures the average blood glucose for the past 2-3 months. FPG: Fasting Plasma Glucose after an overnight fast OGTT: After an overnight fast, a solution with a known amount of glucose is given, and blood samples taken 2 hours after drinking the solution. doc
Diabetes is a Worldwide Epidemic
Affects 425 million people worldwide. Expected to reach 629 million by 2045. (source International Diabetes Federation) About 23.1 million(7.2 %) Americans affected in 2015 (source CDC, National Diabetes Statistics Report 2017) About 5% are estimated to have type 1 diabetes mellitus (T1DM) (Source CDC 2017)
Risk factors for Type 2 Diabetes
Age> 45 Weight> 120% of desirable body weight family history of diabetes in a first degree relative, eg: sibling, parent hispanic, native american, african american, asian, or pacific islander descent history of previous impaired glucose tolerance (IGT) or impaired fasting glucose (IFG) hypertension (140/90), or dyslipidemia (HDL<40mg/dL or triglycerides>150 mg/dL history of gestational diabetes or of delivering a baby weighing >9lb polycystic ovarian syndrome
Midbrain
Also called the mesencephalon. Includes: -Sites of visual reflexes, auditory reflexes; connects the cerebrum and cerebellum; involved in motor coordination -Substantia nigra: important part of the motor circuit; part of the dopaminergic nigrostriatal system -Involved in the behavioral reward system and has been implicated in addiction and psychiatric disturbances The positive reinforcement from abused drugs involves the release of dopamine by axons of the mesolimbic dopamine system. These axons arise in the midbrain and terminate in the nucleus accumbens of the forebrain. Nicotine, opioids (heroin and morphine), cannabinoids (from marijuana), benzodiazepines(Valium and zolpidem), cocaine, and amphetamines are examples of drugs that affect the dopamine systems.
stimulus.
An outside factor that triggers a reaction by the systems and causes a deviation from the set point that is compatible with life.
Regulation of Homeostasis
Analogous to the maintenance of home ambient temperature. Homeostasis uses _________ feedback to maintain optimal conditions. Hormones use ____________ to maintain homeostasis doc
What is an example of other information that might determine the set point that the brainstem uses?
Anxiety would be an example of other information that could determine the set point that the brain uses.
Conduction of the Action Potential
Axons are the only region of a neuron that may be myelinated. Schwann cells are the specific glial cells within the peripheral nervous system that form myelin. These cells form individual myelin sheaths that wrap tightly around the axon in regular intervals. Adjacent to the segments of myelin are exposed regions of the axon referred to as the nodes of Ranvier. Saltatory conduction in myelinated neurons is much faster than continuous conduction, which occurs in unmyelinated neurons. Myelination acts as an insulator along the axon, preventing the leakage of charge across the membrane. This allows the local currents to be maintained and transferred from one node of Ranvier to another. In contrast, the local currents do not travel as far and take longer to reach threshold in unmyelinated neurons. High concentrations of voltage-gated sodium channels are localized within the nodes of Ranvier and are generally lacking within the myelinated regions. This arrangement leads to detrimental consequences in individuals suffering from demyelinating diseases, which include any disorder that causes damage of the myelin sheath. In these diseases, an action potential does not propagate down the axon because the voltage-gated sodium channels are too far apart. Charge will leak across the membrane where the myelin once was, and the nodes of Ranvier containing the voltage-gated sodium channels will not reach threshold. Multiple sclerosis is the most common demyelinating disease. The immune system of individuals suffering from this disease attacks the myelin sheaths found in the central nervous system. This progressive disease is more common in women and is typically diagnosed between ages 20 and 40. Guillain-Barré syndrome is a rare condition in which the myelin sheaths in the peripheral nervous system are attacked by the immune system. Symptoms of this disease range from slight tingling and weakness of the legs to fluctuation in heart rate and blood pressure, which can be life-threatening. Death may occur if the nerves leading to the respiratory muscles become damaged and asphyxiation results. action potentials occur in the unmyelinated regions of an axon Demyelinating diseases cause a(n) decrease in the conduction velocity of action potentials If demyelination occurs, why don't action potentials occur at regions of the axon that were previously myelinated? -These regions lack the appropriate concentration of voltage-gated sodium channels
2.Which components of the nervous system are involved in physical sensation? How do sensory impulses move throughout the body?
Both the CNS and the PNS are involved in physical sensation along with the brain and spinal cord. The CNS sends information to the PNS, whose somatic motor division causes the control of skeletal muscles, and their contraction pulls tendons that are attached to the bones. Overall, this process is responsible for the movement of the body. The somatosensory cortex is present in the brain to process sensory information, and receives information from receptors such as nociceptors and thermoreceptors for pain and temperature respectively. Sensory neurons receive impulses and carry them to the spinal cord or the brain. There, interneurons interpret the signal and provide a connection between sensory and motor neurons. Motor neurons carry impulses from the brain and spinal cord to the muscles.
Dr. Hodges notes that David's exhaled carbon dioxide levels are elevated. List all the metabolic pathways that function to synthesize ATP for skeletal muscle contraction. Which of these pathways produces carbon dioxide as a by-product?
Cellular respiration synthesizes ATP for skeletal muscle contractions. The specific processes within respiration that produce ATP are glycolysis, Citric Acid Cycle, and the Electron Transport Chain, however, the Citric Acid Cycle produces the most ATP. This aerobic respiration produces carbon dioxide as a byproduct.
Name the two major divisions of the nervous system; list the organs/tissues found in each.
Central nervous system: made of the brain and spinal cord, and peripheral nervous system: made of neural tissue outside of the CNS, like motor and sensory neurons.
A cell uses valuable energy to run active transport. Why does a cell need active transport?
Certain molecules that the cell needs (ex: glucose) cannot freely diffuse through the plasma membrane into the cell and therefore need a carrier and energy to enter. The Na+/K+ pump is another example in which energy is required to move ions through the membrane
History of Physiology : Physiology based on Chemical, Physical and Anatomical Methods
Claude Bernard : 19th century. Believed that theories must be tested by experimentation. Recognized cells as functional units of life and discussed "internal environment". Very influential. Michael Foster: 19th century. Established a course on Practical Physiology at the University College in London. Influenced the teaching of Physiology in the US.
What are the different types of MS?
Clinically Isolated Syndrome (CIS) is a first episode of neurologic sympatoms caused by inflammation and demyelination in the CNS. CIS is a characteristic of MS but those who have it may or may not go on to develop MS. RRMS is clearly defined attacks of new or increasing neurologic symptoms and followed by remissions. SPMS follows an initial relapsing-remitting course and those who are diagnosed will eventually transition to a secondary progressive course which involves the worsening of neurologic function. PPMS is characterized by worsening neurologic function from the onset of symptoms, without early relapses or remissions.
Hindbrain
Composed of pons, cerebellum, and medulla oblangata Has cardiovascular and respiratory control centers The pons houses sensory and motor tracts heading from/to the spinal cord. 1)The trigeminal, abducens, facial, and vestibulocochlear nerves arise from the pons 2)Respiratory control centers are found here 3)Surface fibers connect to the cerebellum Cerebellum 1)Second largest brain structure; gray matter outside, white matter inside 2)Receives input from proprioceptors in joints, tendons, and muscles 3)Works with the basal nuclei and motor cortex to coordinate movement 4)Important for memory, motor learning, emotion and higher functions Medulla oblangata All ascending and descending tracts between the brain and spinal cord pass through the medulla
conclusion
Conclusion: The data supports our hypothesis because we had a slower average time, 390.8 ms, drinking water than our undistracted time of 300.6 ms. Some individual changes were greater than others, though all of our reaction times were slower compared to the undistracted time. Individual differences in reaction time can occur due to the method in which each individual drank water, for example the degree to which each person was able to see the green light on the screen, which indicates a difference in the activity of our sensory receptors. When drinking water, our sensory receptors were focused on both drinking, involving taste and feel, and on completing the task, involving vision. This caused slower reaction times as our sensory receptors had to respond to many stimuli. Ultimately, because all of our reaction times were slower than when we did not drink water, this shows that drinking water has a significant effect on reaction times and overall ability to focus on other tasks.
How does Copaxone work as treatment for MS? How do other types of medication differ?
Copaxone is a medication that is similar in structure to a protein found in myelin. This is helpful because MS is an autoimmune disease that attacks the myelin sheath that surrounds the neurons of her CNS. Other medications like corticosteroids can reduce nerve inflammation. Interferon beta medications can reduce the frequency and severity of relapses. Many other drugs are used to reduce the relapse rate.
Fatigue
Decrease in the muscle's ability to generate force. Reversible
Why is there a limit to the amount of shortening that can occur in a sarcomere during muscle contraction?
Depending on the length of the thin filament, it may limit the amount of overlapping that can occur between the thick and thin filaments. This can limit the amount of shortening that can occur in a sarcomere during a muscle contraction.
simple diffusion
Depends on 1. Membrane composition -thickness -cholesterol content -surface area of the membrane 2. Characteristics of the substance -lipid solubility -molecular weight -temperature 3. Energy gradient for the substance - chemical concentration difference - electrical potential
ELISA
ELISA technique is having an antigen immobilized to a solid surface and then paired with an antibody linked to an enzyme. Analysis of the enzyme allows for the detection and measurement of antigens, antibodies, proteins, peptides, and hormones.
Diffusion across a selectively permeable membrane
Diffusion is the net movement of a solute from an area of higher concentration to an area of lower concentration. Diffusion is the result of the random movement of molecules. A concentration gradient is present when there is a different concentration of solutes within a solution. The rate of diffusion may be influenced by density of media, concentration gradient, temperature, molecular size, and membrane permeability. You will place glucose and starch inside dialysis tubing and then place the tubing in a beaker containing iodine and water. You will then observe and record your observations after 10 minutes. Diffusion of these substances across the dialysis tubing will depend on molecular size. Smaller substances will diffuse across the artificial membrane made of dialysis tubing, while larger substances will not. In diffusion, molecules move from high concentration to low concentration. Iodine by itself is brown. When it interacts with starch, iodine turns dark purple The presence of glucose can be tested for by using glucose test strips. -iodine and glucose will be able to diffuse across the dialysis tubing membrane, but not starch due to its molecular size -i will place iodine on one side of the dialysis tubing and glucose and starch on the other. I will then test to determine if diffusion has occurred -diffusion occurred based on molecular size. Iodine and glucose are much smaller molecules than starch; therefore, they were able to diffuse
Explain possible reasons for differences in reaction times between Driver I and Driver II.
Driver I could be younger and therefore have a natural faster reaction time. Driver I could also be a more experienced driver and therefore their muscle memory grants them a faster reaction. Driver II could also have a preexisting condition that makes them have a slower reaction time.
Summarize the reaction times of Driver I at both speeds, comparing baseline reactions to alcohol impaired, reading a text, and texting reaction times:
Driver I had the faster reaction time compared to Driver II at both 35 mph and 70 mph. During the baseline reaction in 35 mph, Driver I had the fastest reaction time with the alcohol impaired reaction speed coming right after it. Texting had a longer reaction time of 0.52 seconds but reading a text message proved to be the slowest reaction time of Driver I in 35 mph. At 70 mph, Driver 1 had the fastest reaction time for the baseline but it was faster than the baseline time in 35 mph. Additionally, the alcohol impared and reading text reaction speeds were the slowest reaction rates in 70 mph, but still faster than those variables in the 35 mph zone.
Summarize the reaction times of Driver II at both speeds, comparing baseline reactions to alcohol impaired, reading a text, and texting reaction times:
Driver II had a faster reaction time for the baseline versus when alcohol impaired, reading a text message, and texting, at both 35 mph and 70 mph. At 70 mph, each individual reaction time was faster than each individual reaction time for 35 mph.
skeletal muscle- electrical stimulation
Electrical impulses from a data acquisition unit can trigger the action potentials generated by nerves that stimulate skeletal muscles in animals. The threshold stimulus is the minimum stimulus required to cause a skeletal muscle to contract. As the magnitude of stimulation increases, a skeletal muscle will contract with increased force due to an increased number of muscle fibers contracting. At maximal stimulus, skeletal muscle contracts at full force and will not contract with any more force even if a greater stimulus is applied. What effect does increasing the voltage have on the force generated? The higher the voltage, the stronger the contraction, up to a maximum force.
Treatment for diabetes
Exercise weight loss Healthy lifestyle Drugs have to do one or more of the following: 1.Stimulate beta-cell secretion of insulin 2.Slow the digestion or absorption of carbohydrates in the intestine 3.Inhibit hepatic glucose release 4.Make target tissues more responsive to insulin
feedback
Feedback involves a system's appropriate response to stimuli to bring a system back to a particular set point.
Organ and organ system
Femur- skeletal system heart- cardiovascular system brain- nervous system skin- integumentary system pituitary gland- endocrine system lungs- respiratory system stomach- digestive system spleen and appendix- lymphatic system uterus- reproductive system kidney-urinary system biceps brachii- muscular system
Do you think you would have more or fewer sarcomeres in an eye muscle?
Fewer sarcomeres compared to a quadricep because the eye muscle is much smaller muscle
What is described in Figures 1, 2, and 3?
Figure 1 shows a relationship between HRV circadian rhythm and COVID-19 status. Figure 2 shows the number of symptom days per participant when evaluating days when participants reported symptoms. Figure 3 shows the relationship between HRV circadian rhythm and symptom onset.
What is HRV and why is it important? How does the sympathetic nervous system affect the HRV versus parasympathetic nervous system?
Heart Rate Variability is a physiological measurement that provides insight into the relationship between the parasympathetic and sympathetic nervous system which controls cardiac contractility and causes variability in beat-to-beat intervals. Low HRV can indicate increased sympathetic balance.
What is Heart Rate Variability and why do the researchers want to study it?
Heart Rate Variability is a physiological measurement that provides insight into the relationship between the parasympathetic and sympathetic nervous system. Changes in the autonomic nervous system function can be characterized by HRV. Researchers want to study it because HRV can predict the onset of infection, something crucial to fighting COVID-19
predict the shape of each RBC after it has reached equilibrium with each solution.
Hypotonic: swell or lyse Isotonic: no change Hypertonic: shrivel
Based on your knowledge of osmosis (refer to model 2), predict the net water movement for each tonicity solution.
Hypotonic: water would move into the cell Isotonic: no movement Hypertonic: out of the cell
The Adrenal Cortex Secretes Mineralocorticoids, Glucocorticoids, and Sex Hormones
Histology of the adrenal gland doc
Does a homeostatic feedback loop only function when there is a change from the set point?
Homeostatic processes are constantly changing within the body and do not cease to operate because set points are always in fluctuation and conditions are always changing. The functioning of the feedback loop depends on how you define the system. If defined by the sensors, then the loops is always functioning. If defined by the effector, then the loop is only functioning when a response is triggered to combat a change outside of the tolerable range of the system.
Do you agree with the conclusions of the study?
I agree with the conclusion of the study, however, in order to confirm the results, I think much more research needs to be done. I agree that it is likely that differences in HRV had a relationship with whether or not someone had a SARS-CoV-2 infection.
What is the most significant table of data?
I think Table 2 is the most significant because it compares the HRV parameters in participants with and without COVID-19 diagnosed. This is what the study aimed to figure out, is there a difference in HRV between someone who has COVID-19 and someone who does not.
HPA Axis
Hypothalamus-Pituitary-Adrenal Axis This is the sequence of 3 hormones; CRH → ACTH → Cortisol Cortisol is secreted from the adrenal cortex and has important roles to play under normal conditions. In addition, it is secreted during periods of stress. Cortisol causes ↑plasma glucose, protein degradation and lipolysis, and suppresses the immune system and has an anti-inflammatory role. Another hormone secreted during stress is epinephrine (and norepinephrine) from the adrenal medulla. Together, cortisol and epinephrine increase the amount of glucose in blood, increase the breathing rate, increase cardiac output, increase blood supply to the skeletal muscles in the limbs and reduce the blood supply to the internal organs, inhibit nonessential activities such as digestion
how does the impermeable solute concentration in the fluid surrounding the cell (the solution) compare to the inside of the cell?
Hypotonic: less than Isotonic: the same Hypertonic: more than
What is InterBeat Interval (IBI)?
IBI is the time difference between heartbeats (normal sinus beats) from which the HRV is calculated.
eponym
If an item or event is named after a person it is called an eponym. For example, Martin Luther King Jr. Day is named after Martin Luther King, Jr. Another example is saxophone, which is named after the Belgian instrument designer and musician, Adolf Sax (see image). In medical terminology, eponyms are slowly being replaced by more descriptive medical terms. For example, the islets of Langerhans, a small island of cells in the pancreas are named after the German pathologist Paul Langerhans, is being replaced with the more descriptive term pancreatic islets. Medical terminology changes slowly, however, and many medical professionals still refer to the pancreatic islets as the islets of Langerhans. List two eponyms that are NOT associated with medicine. A) Teddy bear: named after US President Teddy Roosevelt, who was an avid outdoorsman B) America: named after an Italian map-maker; Amerigo V. C) Caesar salad: named after a restaurant guy who created the salad As a group, try to list three medical eponyms. A) Achilles's tendon B) Braxton hicks' contractions C) Lougehrig's disease
Dantrolene is the only drug available to treat malignant hyperthermia. It works by inhibiting calcium channels of the terminal cisterns of the sarcoplasmic reticulum. Explain how this inhibition helps to terminate skeletal muscle contraction. What effect would this have on David's body temperature?
If the calcium channels are inhibited, there will be a reduction of calcium in the sarcoplasm. Therefore, the troponin will change back to its original shape, cover the myosin binding sites and block interaction between actin and myosin that is needed for contraction. If contraction stops, David's body temperature will decrease back to normal.
Immunohistochemistry
Immunohistochemistry is a microscopy-based technique to detect antigens by using the process of antibodies binding specifically to antigens in tissues. When the antibody and antigen bind, that's when it can be visualized by using an enzyme that speeds up a color-producing reaction.
Explain how each of the hormones above plays a physiological role in 'crisis' situations.
In a crisis, cortisol is released to increase plasma glucose levels, blood pressure, fat and protein breakdown, and it suppresses the immune system. Epinephrine and norepinephrine increase the heart rate, vasoconstrict blood vessels to increase blood pressure, cause bronchodilation to increase the amount of air entering the lungs, and increase cardiac output to increase blood circulation.
The most common feedback loops in the body use the principle of negative feedback. But in some cases, positive feedback occurs for a limited amount of time. One example of this is in the formation of certain clotting factors when blood clotting is initiated. In this scenario the body needs a large number of clotting factors created in a short amount of time. How would a positive feedback loop differ from a negative feedback loop in terms of functional components and responses?
In positive feedback loop the response carried out by the effector enhances the change as opposed to inhibiting it. With regard to the example of clotting, the body would create more clotting factors for a period of time as opposed to inhibiting their production as in a negative feedback loop. Functional components that are part of the stimuli would be self-perpetuated as opposed to self-limited.
3.What components of the nervous system are involved in skeletal muscle movement? How does the motor impulse move throughout the body?
In the efferent division of the PNS, the somatic motor division is responsible for sending signals from the CNS, through nerves, to cause the movement of skeletal muscles. The somatic nervous system is only made up of 1 neuron for each specific muscle and it runs along the length of the body to the target tissue. When a motor neuron inside the spinal cord fires, an impulse goes out from it to the muscles on the axon.
In Model 2, is heart rate (HR) a homeostatically controlled variable?
In the model, heart rate is a response of the effector but not the particular variable being controlled by the loop. Blood pressure is defined as the variable of control. Heart rate is an effect of this variable and of the system but not directly defined as what is being controlled.
List five stimuli that would trigger sensory receptors.
Pain, temperature, smell, taste, light
In the summer, when the weather gets hot, how could this loop be modified (settings or components) to keep the house around the same target temperature?
Instead of using a furnace to respond to changes in the temperature detected by the thermostat, an air conditioning unit could be used to regulate the temperature around the desired temperature set point. The air conditioner would likely reduce higher temperatures and bring the temperature of the system back down. The heat of the external summer environment would likely cause the temperature to rise once the air conditioner stops functioning.
endocrine system effects of blood glucose level
Insulin is produced by the pancreas when blood glucose (sugar) level increases. Insulin causes body cells, especially skeletal muscle fibers and liver cells (hepatocytes), to take in glucose, thus removing glucose from the blood and lowering the blood glucose level. Insulin is vital to the homeostasis of blood glucose level because it is the only control mechanism that causes the blood glucose level to decrease. The pancreas is an exocrine and endocrine organ: Fish can serve as a model organism for insulin shock in humans Normoglycemia is a normal level of blood glucose. -Regular, smooth swimming is a sign of normal behavior in fish. Hyperglycemia is an abnormally high level of blood glucose. -Fast, darting movements are signs of hyperglycemia in fish. Hypoglycemia is an abnormally low level of blood glucose. -Slow, lethargic movements and difficulty moving are signs of hypoglycemia in fish. -Excess insulin can induce a state of hypoglycemia called insulin shock. extensive exercise a diabetic is feeling dizzy what could be done to improve the situation -have the person consume food or drink containing glucose
occipital lobe
Integration of movements in focusing the eye; correlation of visual images with previous visual experiences and other sensory stimuli; conscious perception of vision
temporal lobe
Interpretation of auditory sensations; storage (memory) of auditory and visual experiences
Diffusion is the random movement of molecules until equilibrium is reached.
Is diffusion a form of active or passive transport? Passive because it does not require energy, particles can move freely through the membrane and down their concentration gradient without use of proteins
Diabetic Retinopathy
Leading cause of blindness in developed countries - excessive amount of glucose in the blood stream causes damage to the blood vessels. - within the eye the damaged vessels may leak blood and fluid into the surrounding tissues and cause vision problems. Can be divided into: - Non-proliferative - Proliferative Growth of abnormal blood vessels is in response to high levels of circulating Vascular Endothelial Growth Factor (VEGF)
endocrine: influence of thyroid hormone
Low body temperature can be regulated by increasing the metabolic rate and by shivering. If an organism cannot regulate its temperature through metabolic rate, it will rely on shivering, which requires a greater use of oxygen. The primary effect of thyroid hormone is to promote heat-generating metabolic reactions. Mice will be fed food with and without PTU. A controlled experiment allows comparison between a control group and an experimental (test) group that has been exposed to an experimental factor (the variable). In this simulation, the control group consists of mice fed food without PTU. The experimental group consists of mice fed food with PTU (the experimental factor). Oxygen consumption by the mice will then be measured using a metabolic chamber at different temperatures. Hypothyroidism (low level of thyroid hormone) results in low body temperature. PTU (propylthiouracil) is a compound that blocks production of thyroid hormone by the thyroid gland. A respirometer measures oxygen consumption. Oxygen is used to produce ATP. As oxygen is consumed in the respirometer, the volume of gas decreases. Soda lime is used to absorb the carbon dioxide produced by the mouse so only oxygen consumption is measured. When measuring oxygen consumption, you must take into account the weights of the mice by normalizing the data. -PTU inhibits thyroid hormone. this will decrease the metabolic rate as evidenced by lower (decreased) oxygen consumption from an increase in shivering -I will compare the normalized oxygen consumption at different temp for a control mouse (not treated with PTU) and an experimental mouse (treated with PTU) -thyroid hormone is a key component in temp regulation. Without thyroid hormone, the body must rely more on shivering for temp regulation. This requires more oxygen consumption for ATP generation
central nervous system
Made up of the brain and the spinal cord Receives input from sensory neurons and directs activity of motor neurons innervating muscles and glands. CNS: integrating center PNS:Afferent division: to nervous system Efferent: away from nervous system
Dynamometry
Measurement of power. The graphic record derived from the use of a dynamometer is known as a dynamogram.
Diabetic retinopathy has four stages
Mild Nonproliferative Retinopathy. Earliest stage; microaneurysms (small areas of balloon-like swelling in the retina's tiny blood vessels) occur. Moderate Nonproliferative Retinopathy. As the disease progresses, some blood vessels that nourish the retina are blocked. Severe Nonproliferative Retinopathy. Many more blood vessels are blocked, depriving several areas of the retina with their blood supply. These areas of the retina send signals to the body to grow new blood vessels for nourishment. Proliferative Retinopathy. Advanced stage; the signals sent by the retina for nourishment trigger the growth of new blood vessels. These new blood vessels are abnormal and fragile and grow along the retina and along the surface of the clear, vitreous gel that fills the inside of the eye. By themselves, these blood vessels do not cause symptoms or vision loss. However, they can leak blood, and result in severe vision loss and even blindness.
Why did Molly experience altered sensation in her lower body? Was there something wrong with her skin? Why couldn't she stand? Was there something wrong with the muscles of her leg?
Molly experienced altered sensation in her lower body due to a disruption of the myelinated axons involved in the somatic motor pathway. Signals are delayed or completely blocked, so her skeletal muscles cannot receive signals through the PNS from the CNS, which results in her inability to stand. There is nothing wrong with the muscles of her leg or her skin, but the problem is with the loss of myelin sheath covering the axons in the CNS and PNS.
Did Molly's hearing loss have anything to do with the MS? Why or why not?
Molly's hearing loss may have been related to MS, because MS involves the attach of the myelin sheath, which affects the speed at which signals can be sent, since a myelinated axon will result in a fast signal. As a result, the hearing pathways are damaged, since information cannot be efficiently sent from the receptors in the ear to the auditory cortex where sound information is processed.
Cross Bridge Cycle
Muscle contraction involves a series of events called the cross-bridge cycle -Hydrolysis of ATP by myosin, activates the head for the later power stroke -The ADP and Pi remain bound to the head, which binds to actin forming a cross-bridge -During the power stroke, myosin returns to its original shape, releasing ADP and Pi -ATP binds to the head which releases actin doc
What is myelin and how does it affect the transmission of nerve impulses? Identify the cells responsible for the formation of myelin.
Myelin is an insulating sheath that forms around nerve cells, including those in the brain and spinal cord. It is made of protein and a fatty layer. The myelin sheath allows for electrical impulses to travel faster along the axon, when the sheath is damaged the impulses slow down. Schwann cells are responsible for making myelin in the PNS and oligodendrocytes are responsible for making myelin in the CNS.
Is a negative feedback loop limited to one effector?
No, a negative feedback loop is not limited to one effector. In the case of blood pressure, the effector could the heart (which affects heart rate) or the blood vessel (which can fluctuate their level of constriction).
Does the integrator have to be a separate anatomical structure from the sensor?
No, the integrator does not have to be a separate anatomical structure. The brain can act as the sensor and integrator in some scenarios. The thermostats also acts as the sensor and integrator in the first model.
Endocrine lab background
One of the principles governing human physiology is: Communication and information flow between cells, tissues, and organs is an essential feature of homeostasis and allows for integration of physiological processes. It is essential to maintain coordination among different systems and regulation of the processes is important for homeostasis. Regulation in the body is carried out by both the nervous system and the endocrine system. Nervous system uses a network of neurons and neurotransmitters to regulate the physiological processes. Endocrine system uses a variety of hormones to regulate the various processes in the body
In Model 2B, what is one stimulus for a change in blood pressure?
One stimulus would be a change in one's posture.
true or false
Organs are composed of multiple tissues types. Tissues are composed of multiple cell types. Tissues are NOT composed of multiple organ types Tissue: different types of cells that come together to perform a specific function Within the body, all atoms combine to form molecules. False- because some atoms exist as themselves (Ex: O2 and N2) b) Within the body, all molecules in the body can be found inside cells. False- when we breath in CO2 and O2 it is not within a cell
relationship between osmolality and tonicity
Osmolality (or osmolarity) depends on the molar concentration of the solute and its dissociation factor. It has a unit. You can compare two solutions based on their osmolality. 1 Molal solution of glucose is 1 Osmolal solution 1 Molal solution of NaCl is 2 Osmolal solution The tonicity of a solution depends on the effect of the solution on cell volume at equilibrium and is determined by the relative concentrations of non-penetrating solutes in the cell and the solution. Does not have a unit. Examples of penetrating solutes: Ureaglucose is a slowly penetrating solute.Examples of non-penetrating solutes: NaCl
Describe the methods the researchers designed to achieve the aims?
Participants (health care workers) wore an Apple Watch for the duration of the study which measured their HRV throughout the follow-up period. They also collected surveys assessing infection and symptom-related questions daily.
History of Physiology : Modern Experimental Physiology
Physiology closely tied to anatomy and medicine. Harvey : 17th century : Blood circulation. Beginning of the modern experimental physiology. Based only on anatomical experiments. von Heller : 18th century. Published the first manual of Physiology. Characterized physiology as anatomy in motion. Lavoisier : 18th century. Wrote about the physiological problem of respiration and the production of heat by animals.
Physiology in the 20th Century : A Mature Science
Physiology gave rise to Biochemistry, Biophysics, Molecular Biology. Comparative Physiology still ongoing field of study. Understanding physiology crucial to address pathologies as well as maintaining good health. New breakthroughs being made all the time.
Polygraph
Polygraph is a device that can measure the galvanic skin response along with other variables such as heart rate, respiratory rate and blood pressure. Polygraphy literally means "many measures". Emotions associated with intentional falsification of answers to carefully worded questions involuntarily and subconsciously alters the autonomic output in such a way as to result in recognizable changes in recorded physiological variables. This is because the autonomic nervous system control of heart rate, blood pressure, and sweating cannot be consciously altered. Not a "lie detector test". About one-third of innocent people will fail the "lie detector" test.
Development of Pharmaceutical Drugs
Preclinical Studies: Drug candidates are tested on animal models that may spontaneously (or genetically engineered to) develop human disease. Also known as preclinical toxicology studies. Phase I Clinical Trials: drug is tested on healthy human volunteers. To test safety, absence of toxicity, and to see how the body handles the drug candidate. How the drug is metabolized and how it is handled by the liver, kidneys, and whether there is any effect on the heart, etc... Phase II Clinical Trials: The drug candidate is tested on a larger human population. Tested for both safety and efficacy. Phase III Clinical Trials: Occur in many research centers across the country where a large number of volunteers are recruited. The test population should include both men and women, different ethnicities, should have the disease the drug is targeting, and will be randomly placed in control versus experimental groups. Phase IV: Post-marketing studies. Can reveal any problems with drugs. Can also be used to study the efficacy of the drug against other health conditions.
Asynchronous Recruitment
Recruitment of different motor units within the same to carry out the same task. The number may stay the same but the actual motor units might be different.
RT-PCR
RNA is transcribed into complementary DNA by reverse transcriptase from mRNA in RT-PCR. The complementary DNA is used for the PCR part of the analysis to amplify small segments of DNA. However, RT-PCR is for the analysis of gene expression.
nervous system- monosynaptic reflex
Reflexes are triggered by a stimulus and result in a predictable response. Reflexes are fast and involuntary, which means we are not aware and not in control. Reflexes have four to five main components. The components are listed below: -Receptor: A receptor detects the appropriate stimulus. -Afferent (sensory) neuron: The afferent neuron conducts the signal from the receptor to the spinal cord. -Interneuron: An interneuron may be located within the spinal cord to receive the signal from the afferent neuron. The presence of an interneuron indicates a polysynaptic reflex. -Efferent (motor) neuron: The efferent neuron receives a signal from either the afferent or interneuron and carries the signal to the effector. If the signal passes directly from the afferent neuron to the efferent neuron, it is a monosynaptic reflex. -Effector: The effector executes the response of the reflex. In the spinal reflexes tested in this activity, the effectors are skeletal muscles. Stretch reflexes need not be learned, as they are pre-programmed. They do not change but can be overridden by the central nervous system. monosynaptic reflexes: biceps brachii reflex triceps brachii reflex patellar reflex calcaneal reflex plantar reflex 1. The broad flat side of a reflex hammer is normally used to tap on tendons or ligaments directly. We use this side for patellar, calcaneal, and triceps reflex tests. 2. The pointed side of the reflex hammer is used to touch a finger that is placed over a structure of the body. In this simulation, you will place your thumb on the biceps tendon and strike with the pointed side to test the biceps brachii reflex. 3. The tapered metallic tip of the reflex hammer is used to touch and move over areas of skin. We use it to trigger the plantar reflex Biceps reflex-Flexion at the elbow Triceps reflex-Extension at the elbow Patellar reflex-Extension at the knee calcaneal reflex-plantar flexion plantar reflex- plantar flexion of toes
What are hormones?
Signal molecule produced by an endocrine gland/tissue and secreted into general circulation, to influence target tissues and cells that express specific receptors in the body far from the site of secretion. •Can be a protein, peptide, amine, steroid, or glycoprotein •Has receptors that it recognizes and binds to in or on some cells and not in others •Can act in very small concentrations •Has very specific actions (signal transduction) •The effects of the hormone can be regulated, and/or turned off
summary table transport mechanism-gradient direction-protein carrier?-ATP needed?-molecule examples
Simple diffusion-down-no-no-oxygen,CO2 facilitated diffusion-down-yes-no-amino acids, ions (leak channels) osmosis-against the solute gradient but down its own-no carrier/yes to channel, no, water active transport-up-yes-yes-Na+/K+
Eye dissection
Since human anatomy is similar to that of other mammals, we are able to dissect other species to learn about ourselves. The human eye and the cow eye have many of the same structures. A structure that differs between the human eye and the eye of many other vertebrates is a thin layer of tissue called the tapetum lucidum. This iridescent layer is deep to the retina and acts to reflect light back through the retina to increase vision in dim light. This layer is what makes some animal eyes reflective at night. Humans and most primates do not have this structure.
List as many factors as possible that could alter the reaction time of an automobile driver when required to brake suddenly. Bold all of the listed factors that you have experienced when driving a car.
Singing, looking out the window, eating, intoxicated, adjusting temperature controls or music, talking, texting, putting on makeup, distraction from passengers in the car, sick/injured, prescription or illicit drugs
The rate of diffusion through a membrane is influenced by several factors.
Size of molecules - smaller or larger? Smaller Temperature of molecules - cooler or warmer? Warmer Membrane surface area - less or more? More Membrane permeability - less or more? More Steepness of concentration gradient - less different or more different? More different
Tonus:
Slight tension constantly present to maintain the readiness of the muscle. Results from alternate periodic activation of a small number of motor units within the muscle by motor centers in the brain and spinal cord.
parietal lobe
Somatesthetic interpretation (for example, cutaneous and muscular sensations); understanding speech and formulating words to express thoughts and emotions; interpretation of textures and shapes
electromyography- motor unir recruitment
Somatic motor neurons stimulate skeletal muscles to contract. A motor neuron along with all of the skeletal muscle fibers that it stimulates to contract is called a motor unit. Each muscle has many motor units. Motor units can vary in number from only a few muscles fibers to several hundred muscle fibers. Motor unit recruitment is the addition of motor units to increase the overall contraction strength of a muscle. The force generated by the contraction of a muscle is the contraction strength. Electromyography (EMG) measures the number and frequency of motor units active in a muscle. An electromyogram (EMG) is the recording of the voltage produced by skeletal muscle contraction and is a measure of the active motor units in a muscle. As contraction strength increases, so does the electrical activity recorded by the EMG. You will measure the force, number of active motor units, and frequency of individual motor units. Force is measured as the grip strength produced by squeezing. The purpose of this lab is to examine how motor unit activity changes as the force changes. Note that frequency is reported in Hertz (Hz), which is the number of action potentials per second. In the example below, the duration measurement of 105 ms is rewritten as 0.105 s. To determine the number of Hz, simply divide 1/0.105 s = 10 Hz. The frequency calculation will be done automatically in this simulation. Increasing grip strength will result in increased motor unit recruitment. I will increase grip strength and measure: 1) force and 2) the number of motor units that are active As more motor units are recruited, the force generated increases.
Why do we care?
Some questions to think about. Please take a few minutes and jot down a few sentences of your thinking in response to the following questions. We will go over these questions in lab. Why do we want to study human physiology? How has the study of physiology been improved by study of diseases and vice versa? What does the development of pharmaceutical drugs have to do with the study of physiology? Why is it important to standardize experimentation protocols? Why are new experimental techniques being developed all the time?
What are the symptoms of Covid-19? Why does it spread so easily?
Symptoms include fevers/chills, tired/weak, body aches, dry cough, sneezing, runny nose, diarrhea, sore throat headache, shortness of breath, loss of smell or taste, and itchy eyes. It spreads easily because there is a prolonged incubation period and 30-45% of individuals are asymptomatic SARS-CoV-2 (can spread it unknowingly). It also spreads mostly through respiratory droplets that can travel and remain a long time in the air.
graded and action potential temproal and spatial summation
Temporal and spatial summation of all PSPs determines whether or not threshold is reached. Temporal summation refers to the amount of time between signals being sent from the same presynaptic neuron. The closer these signals are in time, the stronger the graded potential. Spatial summation refers to the relative location of multiple synapses to each other and to their relative distance from the initial segment. Certain drugs cause facilitation of a neuron. Facilitation involves an enhancement of the postsynaptic response, and caffeine is an example of a drug that leads to this phenomenon. Caffeine increases neurotransmitter release from the presynaptic neuron, thereby bringing the postsynaptic neuron closer to threshold and increasing its propensity to develop and propagate action potentials. Nicotine also causes facilitation, but by a different method. Nicotine affects neural transmission by stimulating acetylcholine receptors, which prolongs EPSPs. Reducing the time between signals sent from the same presynaptic terminal increases the strength of the graded potential. This is an example of temporal summation. Substances that cause facilitation of a neuron cause the neuron to fire that may not under the same circumstances in the absence of the facilitator Assume in a laboratory you were able to isolate a neuron and remove the Acetylcholine receptors from the postsynaptic membrane. The substance nicotine would no longer cause facilitation of this neuron. The generation of an action potential, or nerve impulse, occurs once sufficient EPSPs have depolarized the neuron to threshold. The action potential begins at the initial segment (also known as the axon hillock) and travels down the length of the axon towards the axon terminal. Each unmyelinated segment of the axonal membrane goes through a series of events which generates an action potential. These include depolarization, repolarization, hyperpolarization, and return to the resting membrane potential. Each event results in specific changes of the membrane potential caused by the opening and closing of voltage-gated sodium and potassium channels. When voltage-gated sodium channels are open, sodium flows into the neuron making the inside of the cell more positive. The following information best describes the repolarization phase of an action potential. • A membrane potential reading of +10 mV• Inactivated voltage-gated sodium channels • Open voltage-gated potassium channels
There are two classes of hormones produced by the adrenal gland that are both involved in stress response. What are these hormones? Where are they produced? What is the stimulus for each hormone? What is the duration of action of each of these hormones? How does their action end?
The 2 classes of hormones are steroid hormone and amine hormones. Steroid is cortisol and the amines are epinephrine and norepinephrine. Cortisol is produced by adrenal cortex and epinephrine and norepinephrine are produced by the adrenal medulla. CRH stimulates the production of ACTH, and ACTH stimulates cortisol secretion. Sympathetic nervous system stimulation results in secretion of epinephrine and norepinephrine. Cortisol is a steroid hormone, and it takes some time for it to be synthesized and secreted and has long lasting effects. Epinephrine and norepinephrine bind to adrenergic receptors and have shorter response times than cortisol. Both the types of hormones bind to their receptors and their responses will end when the concentration of the hormones decrease.
describe how the H zone differs from the A band.
The A band consists of mostly thick filaments, with some thin filament overlap. The H band is the center of the A band, not containing any thin filament overlap.
The Na-К pump actively transports potassium into the cell and sodium out of the cell across the plasma membrane. Where will the Na and К distribution be high and where will the distributions be low (inside/outside the cell)?
The Na distribution would be high outside the cell and low inside, and the K distribution would be high inside the cell and low outside.
transmissive segment
The action potential is an electrical signal that begins at the axon hillock and travels down the length of the axon towards the axon terminal. Once the action potential enters this transmissive segment of the neuron, it causes the release of neurotransmitters by exocytosis. This series of events results in the transfer of an electrical signal into a chemical signal. Neurotransmitters are released by the presynaptic neuron into the synaptic cleft. Neurotransmitters diffuse across the synaptic cleft and bind to specific receptors on the plasma membrane of the postsynaptic neuron. The binding of neurotransmitters opens ligand-gated ion channels, which results in the production of graded potentials. Neurotransmitters cease to cause graded potentials when they are no longer bound to a receptor. Unbound neurotransmitters are removed from the synaptic cleft by several different mechanisms including: diffusion away from the receptor, uptake into the presynaptic axon terminal, or enzymatic degradation. Acetylcholinesterase is an example of an enzyme that breaks down the neurotransmitter acetylcholine into acetate and choline. Choline is then transported back across the presynaptic axon terminal where it can be reused to synthesize new molecules of acetylcholine. At the synaptic knob, voltage-gated calcium channels open, thereby stimulating the synaptic vesicles to release their neurotransmitters by exocytosis. If acetylcholinesterase became mutated and nonfunctional, what would be the immediate result? -Acetylcholine would build up in the synaptic cleft Neurons need to transfer materials back and forth between the cell body and the axon terminal to function properly. This type of intracellular transport is referred to as axonal transport. Axonal transport depends upon microtubule "tracks" that run the length of the axon and associated motor proteins. Cellular substances and organelles that are produced in the cell body travel in the anterograde direction, moving towards the axon terminal. Other materials, such as recycled membrane vesicles, growth factors, and other chemical signals, migrate back to the cell body through retrograde movement. Both anterograde and retrograde axonal transport are important and necessary to maintain the health of the neuron. Some pathogens take advantage of retrograde transport by "hitching a ride" to the cell body where they infect the neuron. Examples of such pathogens include: tetanus toxin and the herpes simplex, rabies, and polio viruses If a drug was developed that interfered with the proper functioning of the microtubules found within the axons of neurons, how would you expect this to impact axonal transport processes? -Both anterograde and retrograde transport processes would cease The enzyme choline acetyltransferase catalyzes the reaction between acetyl-CoA and choline resulting in the formation of the neurotransmitter acetylcholine. This enzyme is produced within the cell body of neurons, but the synthesis of acetylcholine occurs within the axon terminals. Which statement best describes the axonal transport mechanism associated with this process? -Choline acetyltransferase is transported in the anterograde direction Suppose that a new virus is discovered that specifically infects motor neurons. Assume that this virus enters neurons in conjunction with choline molecules. Once inside the cell, the virus enters the nucleus and replicates. Which direction describes the axonal transport route taken by this virus? -retrograde transport
David's body temperature rises above normal during the surgery (hyperthermia). How does skeletal muscle tissue contribute to body temperature?
The contraction of skeletal muscles, either voluntary or involuntary, causes the release of heat. So, the more skeletal muscle contractions that occur, the more heat that is given off. This allows skeletal muscles to maintain body temperature.
When viewing skeletal muscle through a microscope, you can easily see the dark and light striations of the muscle fiber. Compare the shading in the diagram in Question 15 and in the photograph of muscle fiber as seen through a microscope below. What forms the dark and light bands?
The dark and light bands are formed by thick and thin microfilaments. The light I bands are formed by thin actin filaments. The darker A band is formed of thick myosin filament which causes the cell to refract light.
Experiment
The data for this lab were compiled from male lab rats, two rats per set. One set was the control group and the remaining were experimental group All rats were male to keep it simple; all were given the same food and water and kept under similar conditions All rats except the control rats were injected with a hormone daily for 2 weeks Autopsies were performed on all the rats at the same time. The students carrying out the exercises were disorganized and rushed, making errors. It is now up to you all to make sense of the data and figure out which rat was injected with which hormone. Explain your reasoning when deciding which rat was injected with which hormone.
The specific type of feedback used in model 1 is negative feedback. This determination is based on how the system, or "loop," responds to a detected difference between the measured temperature and the target temperature. With regard to this difference, what is the goal of a negative feedback system?
The goal of a negative feedback system is to bring about change in the opposite direction of the received or detected stimuli to return to a particular set point.
What are the limitations of this study?
The limitations are that there was a small number of participants who were diagnosed with COVID-19 so that limits the ability to determine how predictive HRV can be for infection. Another limitation was that the Apple Watch sporadically collected HRV and only provides HRV in one time-domain. They did not collect data on when participants were sleeping or awake, so therefore fluctuations in sleep patterns may impact HRV readings.
What were the aims of the study? Include the primary and exploratory aims of the study.
The primary aim of the study was to determine whether changes in HRV can differentiate participants infected or not infected with SARS-CoV-2. A secondary aim was to see if changes in HRV can predict the development of a SARS-CoV-2 infection prior to diagnosis by a SARS-Cov-2 nasal PCR. Exploratory aims were to determine whether changes in HRV can detect the presence of COVID-19 symptoms, determine if changes in HRV can predict the development of COVID-19 symptoms, and to measure how HRV changed throughout the infection and symptom period.
Scientific Method
The scientific method is a process that involves the formation and testing of hypotheses. The scientific method usually involves at least four main steps: 1.Hypothesis 2.Experiment 3.Analysis 4.Conclusion A hypothesis is a formulated statement of predicted behaviors. A controlled experiment allows scientists to test hypotheses and to draw conclusions based on reproducible results. A controlled experiment allows comparison between a control group and a test (experimental) group that has been exposed to an experimental factor (the variable). In the analysis phase, the results of the experiment are examined for agreement with the hypothesis. Any differences that are observed between the two groups can be attributed to the effects of the experimental factor. The conclusion includes a representation of the results and a discussion regarding the confirmation or rejection of the original hypothesis. Pillbugs are considered omnivores. They feed on live or decaying plant material, fungi, and dead animals. Pillbugs detect food using a sense similar to smell. When a pillbug is attracted to a substance, it will move toward it. This is termed a positive response. When a pillbug is repelled from a substance, it will move away from it. This is termed a negative response. The sand used in the experiment is clean and void of any contamination. It provides no nutrients but feels like cornstarch. Pillbugs are not repelled from sand. The cornstarch used in the experiment contains many organic nutrients. It has a similar texture and feel to sand. A choice chamber has two sides, and there is a channel in the middle that connects the right and left chambers, allowing the pillbugs to move to either side. -pillbugs tend to move toward the cornstarch, and the control group show they dont change behavior regarding sand
pupillary reflex test
The size of each pupil is adjusted by muscles in the iris based on light intensity and object distance. The adjustment of the pupil due to light intensity is called the pupillary light reflex (also called photopupillary reflex). When relatively bright light enters one or both eyes, both pupils will constrict (get smaller) together. This is a parasympathetic reflex of the autonomic nervous system (ANS) that is controlled by the sphincter pupillae muscle of the iris. When relatively dim light enters one or both eyes, both pupils will dilate (get larger) together. This is a sympathetic reflex of the ANS that is controlled by the dilator pupillae muscle of the iris. The two muscles of the iris are innervated by the oculomotor nerve (cranial nerve III). Pupil constriction is also one of three mechanisms for focusing light on the retina when viewing objects closer than 20 feet away. Accommodation of the lens and convergence of the lens are the other two mechanisms. These are both covered in separate simulations. When viewing a near object, both pupils will constrict to reduce the amount of light entering the eyes. This makes the field of view more focused on the fovea centralis, which is the most sensitive and acute area of the retina. The pupillary light reflex tests the function of the oculomotor nerve (cranial nerve III) and requires regions within the brain to function normally. It is part of a routine eye exam and is also used to test for a possible concussion injury. In the pupillary light reflex, both pupils constrict simultaneously when exposed to bright light and dilate in low-light level situations. Both pupils also constrict simultaneously when an object is moved closer to the eyes. The pupils constrict when we focus on a nearby object so the object can be better focused onto the retina
develop a definition of the sliding filament theory with regard to thick and thin filaments.
The sliding filament theory states that myosin, or thick muscle filaments, slide past actin, or thin muscle filaments, during contraction.
The sliding filament theory is used to explain the physiology of skeletal muscle contraction.
The sliding filament theory states that our filaments slide past each other in order for a muscle to contract. More specifically, the myosin slides past the actin.
What is the most likely cause of a change in the target temperature (set point)? Is this change determined by one of the components of the loop itself?
The target temperature of the system is determined by an external factor (the person setting the thermostat) and changes in the target temperature could only be changed by a person.
The homeowner is growing Northern Australian orchids in the house. These orchids only grow in temperatures above 22 degrees Celsius. If the thermostat or the wire from the thermostat to the furnace breaks, what will happen to the temperature in the house? What will happen to the orchids? (Assume that it is winter in a northern climate and it is cold outside).
The thermostat would be unable to detect changes in temperature, thus the furnace would not be able to function to heat the house. The orchids unable to withstand cold temperatures would die as a result of the furnace's loss of function. Homeostasis could not be maintained in a range that is compatible with the life requirements of the orchids.
Normal plasma osmolarity is about 300 mosm/kg. An elderly woman with diabetes has elevated blood glucose levels that raise her blood osmolarity to 310 mosm/kg. In this diabetic patient, predict the water movement, if any, of the extracellular fluids and the shape of her red blood cells. (Hint: the diabetic cells are initially in an isotonic fluid that is the same as normal blood).
The water would move out of her cells, causing them to shrivel slightly.
osmosis: tonicity in red blood
There are 3 types of osmotic environments: isotonic, hypotonic, and hypertonic. An isotonic environment is balanced so water enters and leaves cells at the same rate. A hypertonic environment tends to cause a cell to shrivel or collapse as water exits the cell. A hypotonic environment tends to cause a cell to swell or burst as water enters the cell. You will mix whole blood with solutions of different salt concentrations and determine the tonicity of each solution. You will then look through the tube to see if the resting solution is cloudy (opaque) or clear (translucent). You will then look at the red blood cells under the microscope to determine if the cells have burst, are normal, or are crenated. When red blood cells are exposed to hypotonic solution, they swell and burst. Because the cell membranes are no longer intact, the solution will be clear (translucent). When red blood cells are exposed to isotonic or hypertonic solutions, their cell membranes stay intact and will cause the solution to be cloudy (opaque). -red blood cells placed in a hypertonic solution will shrink because osmosis will draw water out of the cells, causing their volume to decrease -i will place red blood cells into solutions with different tonicities, and I will examine the appearance of the cells under a microscope to see if the cells change -the cells exchange water with the solutions based on tonicity because the cells have selectively permeable membranes
Minnesota Arrest Data for 2009 records 26,240 drivers of all ages were arrested for driving under the influence of alcohol in that year (Century Council statistic). According to the National Highway Traffic Safety Administration (NHTSA), 33,808 people died in traffic crashes in 2009 in the United States, including an estimated 10,839 people who died in drunk driving crashes, accounting for 32% of all traffic deaths last year. Predict which increases the reaction time more for drivers required to brake suddenly: driving under the influence of alcohol or driving while texting:
They are both bad, but texting is better for reaction time because your motor functions are not impaired.
Did the length chance between relaxed and contracted sarcomeres?
Thick filament: no thin filament: no A band: no I band: yes H zone: yes sarcomere: yes The sarcomere shortens when thin and thick filaments overlap. The filaments do not shorten but overlap, causing a shortening in the sarcomere as a whole.
Why do we care about this study? Why were you assigned to critically read this paper and draw your own conclusions?
This pandemic is destroying the lives of millions of people, we need to explore every single possibility of a solution in order to solve it. If we could find a way to diagnose COVID before symptoms set it, then we could drastically reduce the spread. I was assigned to critically read this paper because it is topical to my everyday life and teaches me different ways in which knowledge of physiology can solve disease in all possible ways. It is important I read this with my own scientist's view in mind because I could one day be conducting a similar study.
Thyroid
Thyrotropin Releasing Hormone (TRH) is released from the hypothalamus, which stimulates the anterior pituitary to secrete Thyroid Stimulating Hormone (TSH) which travels through circulation to arrive at the thyroid and stimulate the thyroid to secrete Thyroxine (T4). TRH → TSH → Thyroxine The active thyroid hormone is T3. T4 is converted to T3 inside target cells. Thyroid hormone helps maintain normal Basal Metabolic Rate (BMR) and increases heat production in the body. It is necessary for proper central nervous system development and influences the growth rate of many body tissues. Excessive TSH secretion can increase the size of the thyroid gland and this is called a goiter.
visual acuity
Visual acuity is the ability of the lens of the eye to change shape and focus light rays from a faraway object on to the retina. Visual acuity is determined to be normal, myopic, or hyperopic. Normal Vision (Emmetropia) The Snellen chart on the left is read by the patient as far down as possible. The image on the right shows how light is focused on the retina in a person with 20/20 vision. Myopia The Snellen chart on the left is blurry. The image on the right shows how light is focused in front of the retina. This is also called nearsightedness because the point of focus is too close to the lens. Hyperopia The Snellen chart will be clear. However, the person will have trouble with images that are close. The image on the right shows how light is focused behind the retina. This is also called farsightedness. A person with a normal ability to focus on faraway objects will clearly see all letters up to row 8 on a Snellen eye chart. This is categorized as 20/20 vision. What does 20/20 vision mean?In the number 20/20, the top number refers to the fact that it is standard to do this test 20 feet from the Snellen chart. The bottom number gives the distance in feet that a person with normal vision should recognize letters at 20 feet. A person with a 20/40 vision rating recognizes from 20 feet what someone with normal vision can identify from 40 feet. This person is nearsighted (myopic). A person with a 20/10 vision rating recognizes from 20 feet what someone with normal vision can only identify from 10 feet. This person has excellent vision. How to read the Snellen chart. Determine the lowest line you are able to read. Read the vision rating corresponding to that line. Use the phoropter to correct vision by increasing or decreasing the diopter (correction) setting. Determine the lowest power for which the vision becomes sharp. Diopter: 0: Emmetropia (normal) Diopter: 2.00: Hyperopia (farsightedness) Diopter: -1.25: Myopia (nearsightedness) Hyperopia (farsightedness): Convex lenses Myopia (nearsightedness): Concave lenses
What are wearable devices used in healthcare?
Wearable devices are used for remote sensing and provide the ability to measure physiological parameters like heart rate, sleep, activity, and heart rate variability
Skeletal Muscle Contraction process
When a muscle is relaxed, its myosin heads cannot bind to actin because the attachment sites are blocked by tropomyosin -In order for muscle to contract, tropomyosin must be removed by troponin -This process is regulated by Ca2+ levels in the muscle fiber sarcoplasm -In low Ca2+ levels, tropomyosin inhibits cross-bridge formation -In high Ca2+ levels, Ca2+ binds to troponin -Tropomyosin is displaced, allowing the formation of actin-myosin cross-bridges doc A muscle fiber is stimulated to contract by motor neurons, which secrete acetylcholine at the neuromuscular junction -The membrane becomes depolarized -Depolarization is conducted down the transverse tubules (T tubules) -Stimulate the release of Ca2+ from the sarcoplasmic reticulum (SR) doc A muscle stimulated with a single AP quickly contracts and relaxes in a response called a twitch Summation is a cumulative response when a second twitch "piggy-backs" on the first Tetanus occurs when there is no relaxation between twitches -A sustained contraction is produced doc
Choose another stimulus from Q. 3 that will initiate a CNS motor response that will travel via the other motor division (SNS/ANS) of the peripheral nervous system (PNS) described in Q. 5.
When you feel pain, the sensory receptors in our skin send a message via nerve fibers to the spinal cord where the pain is registered, this triggers a reflex through motor neurons to remove the body part from the source of pain. This is part of the SNS motor division.
Molecular Techniques: Visualization
When, Where and How Much? •Temporal expression -Stable or dynamic? •Spatial expression -ubiquitous or restricted? •Concentration -Do levels change with a given treatment or with pathology? •Tissue and cell structure -Staining -microscopy •RNA -Northern Blot -RT-PCR -microarray -In situ hybridization •Protein -Western blot -Immunohistochemistry -ELISA •Autoradiography -Radioactive label
Should the laws for texting while driving be as severe as the laws for driving under the influence of alcohol? Support your position with anatomical and physiological evidence from your test data in addition to the data above.
Yes, because texting decreases the reaction time rate more than drunk driving, it should have equal if not worse penalties. As we can see from the chart, for both Driver I and Driver II, the reaction rate times for reading a text message were equal to or slower than the reaction rates when impaired. Texting while driving distracts the driver completely because their sensory receptors are not reactive to what is on the road and the prefrontal cortex is being used to focus on texting rather than processing what is on the road. When drunk driving, alcohol impairment depresses the nervous system leading to slower reaction times, however a person can maintain a greater degree of focus on the road than when texting.
Key Concepts reaction time
Your nervous system allows to react to the external environment (external stimuli) Reactions can be voluntary or involuntary Stimulus →Sensory Neuron → Spinal Cord or Brain → Motor Neuron →Response Simple Reaction Time Recognition Reaction Time Choice Reaction Time Serial Reaction Time
Assuming that the feedback loop in Model 2B is functioning properly, predict what will happen to heart rate (HR) if the following changes occur:
a) Blood pressure decreases: heart rate increases b)Blood pressure increases: heart rate decreases
During malignant hyperthermia, there is an increased amount of calcium released into the sarcoplasm of skeletal muscle cells.
a. What organelle stores calcium in muscles cells? the sarcoplasmic reticulum b. Describe the events that must occur in the muscle cell before calcium is released from this organelle. Motor neurons stimulate a muscle fiber by secreting ACh into the neuromuscular junction. The depolarization of the membrane is conducted down T tubules to stimulate the release of calcium from the sarcoplasmic reticulum.
secondary active transport
a.Also called coupled transport b.The energy needed to move molecules across their concentration gradient is acquired by moving sodium back into the cell. c.Since the sodium was originally pumped out of the cell using ATP, this is considered active transport. d. Cotransport or symport - the other molecule is moved with sodium. This is the common way to transport glucose e.Countertransport or antiport - the other molecule is moved in the opposite direction from sodium. E.g. Uphill movement of Ca+2 doc
transport across epithelial membranes
a.Involves transcellular transport: movement of molecules through the cytoplasm of the epithelial cells b.May also involve paracellular transport: movement across the tiny gaps between cells c. Involves many different types of carrier- mediated proteins at both ends of the epithelial cells such as the Na+/K+ pump or the Na+/H+ pump d. Paracellular transport is limited by junctional complexes Eg: transfer of maternal antibodies in breast milk from mother to infant. doc
membrane transport
controlled exchange of material
A wilderness firefighter has just completed 12 hours of fighting a forest fire. She followed procedure carefully by drinking water or gatorade every hour for the 12 hours but towards the end of those 12 hours she overheated and vomited twice, losing both fluid and ions. After wards, she exhibited signs of a possible osmotic imbalance. Answer the following questions based on this situation: (5 points) a. After vomiting, she was treated by local paramedics who gave her 500 ml of water to drink. By drinking the water did the firefighter increase or decrease her body osmolarity?
decrease
cerebellum microscope
doc
islet of langerhans
doc
multipolar neruon
doc
pancreas
doc
peripheral nerve cross section
doc
thyroid gland
doc
Regulation of hormone levels by Feedback Inhibition
doc *
What is an Endocrine Gland?
ductless glands doc
passive transport
for the side of the model with passive transport, the high solute concentration would be on the top of the diagram and low concentration would be on the bottom how do solutes move along their concentration gradient? They move down the concentration gradient (high to low) Passive transport moves solutes _down_ a concentration gradient
What structure is the link between the nervous system and the endocrine system?
hypothalamus
In situ hybridization
in situ hybridization is an analysis that detects and finds specific nucleic acids. The nucleic acid sequence is bound by complementary base pairing with a detectable part called a probe to localize a specific DNA or RNA sequence in a section of tissue.
Tonicity
is the ability of a solution to change the shape (tone) of a cell by altering its internal water volume.
Sodium Glucose Transporter (SGLT): Secondary Active Transport
lactose, sucrose->glucose->absorbed by glucose reabsorption in kidney doc
What is the physiological response over time as a result of an over-active thyroid gland? What about an underactive thyroid gland?
overactive: acceleration of metabolism, unintentional weight loss, rapid or irregular heartbeat underactive: weight gain, slow metabolism, slow heart rate
trh tsh acth cortisol table
pituitary gland thyroid gland thymus gland adrenal gland body weight Put a '+' in a cell if you would expect an increase in the size of a gland or in body weight (bottom row); put a '-' in the cell if you would expect to see a decrease in the size of the gland or in body weight if an animal were treated daily with the hormones noted at the top of the table. Leave a cell in the table empty if you do not expect to see a change in a gland's size.
If blood pressure is too high,
there would be strain on the blood vessels which can cause an aneurism and the brain would normally tell the heart to beat slower the compensate for the change.
Physiology is an Integrative Science
•Integration across many levels of organization •Complex systems have emergent properties •Concept mapping •Organizational tool for relationships and processes •Experimental Physiology •Evidence-based medicine •Translational research
protein mediated transport
• Protein mediated transport not requiring energy: Facilitated diffusion Down the concentration gradient. Example is movement of glucose by GLUT molecules. • protein transporters involved: move molecules across membranes -two types: channels and carriers -channels: water filled passages between the ECF and the ICF -carrier proteins: bind to the molecules they are transporting • Protein mediated transport requiring energy : Active transport Going against the concentration gradient. Examples are Na+-K+ ATPase, Ca+2 ATPase • Protein transporters : Move molecules across membranes.• Two types : Channels and Carriers• Channels : Water filled passages between the ECF and the ICF• Carrier proteins : Bind to the molecules they are transporting ATPases pump ions/molecules involved in primary active transport carrying out coupled transport involved in secondary
Human subjects research
•Behavioral •Clinical trials •Disadvantages: -Confounds, variability -Compliance -Ethics •Solutions: -Single-blind -Double-blind studies -Randomized controlled trials -Placebo control (placebo effect, nocebo effect) -Crossover study
Experimentation in Physiology
•Biochemical •Cell/Molecular (in vitro) •Animal Studies (in vivo) -Many classic physiological studies -Advantages and disadvantages? •Translational Research ("Bench to Bedside")
Human Physiological Measurements
•Concentration of biomolecules: -Blood/Serum/Plasma -Urine -Saliva -CSF •Imaging: -X-Ray, CT scan -Ultrasound, echocardiogram -MRI, fMRI, DTI -PET scan •Electrical activity -EKG, EEG, EMG •Blood Pressure, heart rate
Prospective Studies
•Framingham Heart Study -1948-present; 3 generations -N=5,209; age 30-62 -BP, cholesterol, obesity, genetics -1200+ papers published •Nurses Health Study, 1976, 1989, 2010 -238,000 nurses -Questionnaires (2 years), blood samples, toenails -90% response rate -Lifestyle, diet, cancer, heart disease -GUTS: children of participants •National Children's Study -Environmental influences on development -100,000 children; 30 study centers -Conception - age 21
Muscle Contraction
•Muscle tension: force created by muscle •Load: weight that opposes contraction •Contraction: creation of tension in muscle •Relaxation: release of tension •Steps leading up to muscle contraction: -Events at the neuromuscular junction -Excitation-contraction coupling -Contraction-relaxation cycle
