Final E109
Based on the above plot of Lung volume over time what is the measured tidal volume in ml for this individual's first breath? (Pic 22)
(2700-2000) = 700 ml Answer 700 ml
If a person's normal pulmonary dead space is 150 ml and tidal volume is 500 ml, what would be their tidal volume in ml to achieve the same volume of inhaled air reaching the alveoli of that person was breathing through a snorkel with a volume of 230 ml?
(500ml - 150 ml = 350ml) (500ml + 230 ml = 730ml) So answer is 730
The integration center of reflexes are located in the (answer 1) where efferent signals are sent to (answer 2) and ascending commands first travel through the (answer 3) before being processed in the (answer 4) allowing us to consciously feel reflexes.
1. Spinal cord 2. muscles 3. thalamus 4. somatic sensory cortex
Select the correct order of changes that occur in the air tract when the diaphragm contracts :
1. Thoracic cavity increases in volume 2. alveolar pressure decreases 3. air from outside the body will rush into the lungs
Which of the following brain centers control the autonomic nervous system? 1. Pons: 2. Hypothalamus: 3. Cerebellum: 4: Medula oblongata:
1. Yes, it helps control the autonomic nervous system. 2. Yes, it helps control the autonomic nervous system. 3. No, it does not control the autonomic nervous system. 4. Yes, it helps control the autonomic nervous system.
Polysaccharides, or large carbohydrates, are broken down into disaccharides within the small intestine by (answer 1) . These disaccharides are then further broken down into monosaccharides like glucose by (answer 2).
1. amylase secreted by pancreas 2. enzymes secreted by the brush border
Multiple types of _______ tissue include collagen fibers, which provide stiffness and elasticity. ______ tissue is largely composed of extracellular components, such as ground substance, whereas transport _____ tissue functions by transporting molecules through cells.Options: muscle; connective; nervous; epithelial
1. connective 2. connective 3. epithelial tissue
Choose the answers that best complete the following sentences. Reciprocal inhibition is necessary when voluntarily moving and serves to inhibit (answer 1) from contracting. This ensures the (answer 2) can contract effectively.
1. generating stretch reflexes 2. antagonist muscles 3. agonist muscle
1. Elevated blood volume causes (answer 1). 2. Which prompts release of (answer 2). 3. This triggers (answer 3) in vessels leading to the glomeruli. 4. The (answer 4) blood flow to glomeruli (answer 5) the filtration rate. 5. Ultimately leading to (answer 6) excretion of water.
1. increased stress in atrial myocardial cells 2. atrial natriuretic peptides (ANP) 3. vasodilation 4. The increased 5. increases 6. increased
Blood leaving the heart enters (answer 1) vessels where the flow speed is (answer 2), which ensures (answer 3)
1. large 2. relatively high 3. quick delivery of gases and nutrients
When the left ventricle relaxes during diastole, the (answer 1) will open due to (answer 2), while the (answer 3) valve remains closed because (answer 4).
1. left AV valve 2. a higher pressure within the atrium and lower pressure in the ventricle 3. left Semilunar valve 4. lower pressure in the left ventricle
_______ channels are critical for human hearing, whereas ____ channels respond to neurotransmitters, and ____ channels respond to changes in electrical activity across a membrane .Options: optically-gated; mechanically- gated; ligand- gated; voltage-gated
1. mechanically-gated 2. ligand-gated 3. voltage-gated
Ledig cells produce (answer 1) which stimulates the Sertoli cells to(answer 2) (sperm production). Males still produce gonadotropin releasing hormone (answer 3) from the hypothalamus and secrete Luteinizing Hormone (answer 4) and Follicle Stimulating Hormone (answer 5) from the anterior pituitary gland even though they do not have follicles.
1. testosterone 2. stimulate spermatogenesis 3. (GnRH) 4. (LH) 5. (FSH)
By what factor would resistance to blood flow change if an arterioles reduces its radius in half?
16
Imagine an exercising muscle cell that requires a constant supply of oxygen to avoid fatigue. At which of the following distances from a capillary would you predict these muscle cells to have sufficient oxygen delivery?
2 μ m and 100 nm
Put these events in the correct chronological sequence: 1. End-plate potentials trigger action potentials 2. Action potentials move the interior of the cell along the T-tubules 3. Acetylcholine binds to receptors on the motor end plate 4. Binding sites on actin are uncovered, allowing myosin to bind and carry out power strokes 5. Ca2+ is released from the sarcoplasmic reticulum 6. Chemically regulated ion channels open, causing depolarization 7. Ca2+ ions bind to troponin-C, pulling on tropomyosin
3,6,1,2,5,7,4
If the heart pumps 5 Liters of blood per minute, what is the rate of flow of blood through the pulmonary veins?
5 L/min
Based on the above plot and that this individual's pulmonary dead space is 200 ml, what is the volume of of alveolar ventilation at time i? (Pic 22)
500 ml
John fills the cuff of his sphygmomanometer and then lets the air out. The korotkoff sound starts and finishes when the dial says 160 and 100, respectively. What are John's pulse pressure and mean arterial pressure?
60; 120
You measure your friend's pulmonary anatomy and find that their functional residual (lung volume at the end of passive expiration) is 2500 ml in volume and their dead space is 200 ml, if they have a tidal volume of 1000 ml while jogging what is the volume of fresh air reaching the alveoli with each breath?
800 ml
Low concentration of glucose in the plasma are senses by (answer 1) which act both as sensory receptors and as the integration center. Their activation then prompts the release of (answer 2) which stimulates the liver to (answer 3).
Answer 1: a cells in the pancreas Answer 2: glucagon Answer 3: concert glycogen to glucose
Secretin is a hormone that is released because of (answer 1). This hormone stimulates the release of (answer 2) into the small intestine from the (answer 3) as well as (answer 4). It ultimately (answer 5).
Answer 1: a low pH in the small intestine Answer 2: bicarbonate Answer 3: pancreas Answer 4: inhibition of hydrochloric acid secretion in the stomach Answer 5: raises the pH of chyme in small intestine and neutralizes pepsin
Match the function to the appropriate cardiac cell; autorhythmic (pacemaker) cells, contractile cells, or both. Creates heart beat through autonomous activation (answer 1) Generates force (answer 2) Has 'funny' (IF) channels (answer 3)
Answer 1: autorhythmic Answer 2: contractile Answer 3: autorhythmic
Smooth muscles can attain a 'latch state' by (answer 1) intracellular concentrations of (answer 2) and ultimately allows them to save (answer 3). Cardiac muscles use (answer 4) to transmit signals between one another and are characterised by (answer 5) Ryanodine receptors (RyR).
Answer 1: decreasing Answer 2: Ca2+ (calcium) Answer 3: ATP Answer 4: gap junctions Answer 5: Ca2+ activated
The (answer 1) is the location within the kidney that sets the minimum osmolarity of the filtrate as it moves through the collecting duct. The (answer 2) is the location within the kidney that sets the maximum osmolarity of the filtrate as it moves through the collecting duct.
Answer 1: distal tubule Answer 2: interstitial fluid deep within the Medulla
The uvula protects against (answer 1), while the epiglottis protects against (answer 2) triggered by a reflex that is stimulated when (answer 3).
Answer 1: food entering the nasal passages Answer 2: food entering the trachea Answer 3: stretch receptors in the back of the throat are activated
Match the following muscles to their effect on the volume of the thoracic cavity and whether or not it helps with inspiration or expiration. Diaphragm: answer 1 Intercostals: answer 2 External intercostals: answer 3 Scalene muscles: answer 4 Abdominals: answer 5
Answer 1: increases thoracic cavity volume for inhalation Answer 2: decreases thoracic cavity volume for exhalation Answer 3: increases thoracic cavity volume for inhalation Answer 4: increases thoracic cavity volume for inhalation Answer 5: decreases thoracic cavity volume for exhalation
Match the following ways of control king osmolarity in the body with their correct definition. Filtration : answer 1 Reabsorption : answer 2 Secretion : answer 3 Excretion : answer 4
Answer 1: indiscriminately removes solutes from blood into filtrate Answer 2: Allows body to uptake nutrients in filtrate back into blood Answer 3: remixes solutes by actively pumping them from blood into filtrate Answer 4: removal of filtrate from the body
Choose the answers that best complete the following sentence. When the left ventricle relaxes diastole, the (answer 1) will open due to a (answer 2), while the (answer 3) valve remains closed because of (answer 4).
Answer 1: left AV valve Answer 2: a higher pressure within the atrium and lower pressure in the ventricle Answer 3: left semilunar valve Answer 4: lower pressure in the left ventricle
Filtrate in the glomerulus is relatively (answer 1) in osmolarity compared to urine. As the filtrate travels down the descending limb of the loop of henle the osmolarity (answer 2). Then, as the filtrate travels up the ascending limb of the loop of henle the similarity (answer 3). Finally, as it descends through the collection duct, the osmolarity may (answer 4) before existing into the ureter.
Answer 1: low Answer 2: increase Answer 3: decreases Answer 4: increase
1. High osmarity in the blood is sensed by (answer 1). 2. These receptor cells then (answer 2) and stimulate (answer 3) 3. The following depolarization of the cells causes the release of (answer 4). 4. This hormone then increases (answer 5).
Answer 1: osmoreceptors in the hypothalamus Answer 2: shrivel or shrink in size Answer 3: mechanically -gated channels Answer 4: vasopressin Answer 5: reabsorption of water in the kidneys to maintain water in the body
Match the following characteristics to either polysynaptic, monosynaptic reflexes or both. Presence of interneurons in circuit. Answer 1 Multiple synapses in parallel. Answer 2 Multiple neurons. Answer 3 Multiple neurons in pathway. Answer 4
Answer 1: polysynaptic Answer 2: both Answer 3: both Answer 4. Polysynaptic
The musculoskeletal (answer 1) consists of (answer 2), including the bones and muscles. Bones and muscles are bound by connective (answer 3), which are largely comprised of collagen (answer 4).
Answer 1: system Answer 2: organs Answer 3: tissues Answer 4: molecules
Cholecytokinin (CCK) is a hormone that is released because of (answer 1). This hormone stimulates the release of (answer 2) into the small intestine from the (answer 3). It ultimately causes (answer 4).
Answer 1: the presence of fats in the small intestine Answer 2: bile Answer 3: gall bladder Answer 4: they chyme to move slower through the small intestine by inhibiting smooth muscle contraction
Use the above diagram, match the Roman numeral to the correct anatomical structure of the respiratory system. (Pic 21) i : answer 1 ii : answer 2 iii : answer 3 iv : answer 4
Answer 1: trachea Answer 2: Lung Answer 3: thoracic cavity Answer 4: diaphragm
Choose the diagram that best represents the stretch (myotatic) reflex pathway of the quadriceps muscle.
Answer in pic 11
The below graphs show the membrane potential of individual synapses on a dendrites (red and blue curves), as well as the overall membrane potential of the cell body (black, dashed curve). Choose the graph that illustrate temporal and spatial summation in a neutron
Answer in pic 4
The above figure illustrates the rate of production of Creatinine as a function of its concentration within the plasma. Why does the slope decrease after 300 mg/100 ml of Creatinine in the blood?
At this point secretory pumps are saturated so only filtration allows for increased production rates
Based on the above Wigger's diagram, select all of the following that are true between times ii and iii. (Pic 12)
Atria diastole is occurring Ventricular systole is occurring The right ventricular volume is decreasing
Select all that apply during the Q-R-S Complex of an electromyocardiogram (ECG) recording.
Atrial repolarization. Ventricular depolarization.
What factors increase the propagation speed of an action potential?
Axon diameter Myelination
Select all of the following TRUE statements. Options: a)Adipose tissue has a crystalized matrix. B) All connective tissue includes cells. C) Ground substance may be a liquid.
B) All connective tissue includes cells. C) Ground substance may be a liquid.
Select all the principles that correctly describe how the heart pumps blood
Chamber contraction decreases volume Chamber contraction increases pressure Blood moves toward lower pressure Valves prevent back-flow
Select all of the forms of mechanical digestion available in the mouth and stomach.
Chewing with teeth tears and grinds food. Contraction of circumferential and oblique muscles to move food in stomach.
Contraction of the sphincter between the esophagus and stomach serves what purpose?
Closes off the connection, preventing stomach acid from reaching the esophagus.
What causes the sound associated with a heart beat?
Closing of AV valves and semilunar vavles
Contraction of the spinster between the stomach and small intestine serves what purpose?
Closing of the connection keeping food from moving prematurely into the small intestines.
What generates sound during a heart beat?
Closure of the AV valve
Why is the diastolic pressure in the aorta higher than. The left ventricle?
Collagen fibers in tension passively maintain high pressure in the aorta
Imagine a situation where the hydrostatic pressure within a capillary is 60 mm Hg and the hydrostatic pressure surrounding the capillary it is 30 mm. The net osmotic pressure between capillary and interstitial fluid is 35 mm Hg. TRUE or FALSE: Filtration from the blood will occur.
F
Use the above Hemoglobin-Oxygen Saturation curves answer the following question. Given that intense exercise produces lactic acid and CO2 that lowers the pH. Is it true or false that the blue curve would represent the Hb-O2 saturation curve during intense exercise and the red curve represents the conditions at rest? (Pic 20)
False
Assume that two muscles are cylindrical in a shape and equal in length, but muscle B has twice the radius of muscle A. By what factor is the maximum force of B greater than A?
Force B/ force A = (kπ(2R)^2)/ (kπR^2) =4
Which of the following factor(s) help blood be filtered in the glomerulus inside the kidneys?
Higher net hydrostatic pressure than net colloid pressure.
Andrew has defective alpha receptors on his arterioles casing him to be less responsive to norepinephrine. This might cause chronic (answer 1) because his arterioles simply won't (answer 2) in response to increased norepinephrine levels.
Hypotensions; constrict
Select all of the following ways which the sympathetic nervous system controls heart contractions.
Increases duration of If (funny) channels shortening pacemaker potential phase. Increases Ca2+ concentration in contractile cells. Norepinepherine (NE) binds to receptors on pacemaker cells.
How does the vasopressin control water permeability in the collection duct of nephron?
Increasing aquaporins in membranes of epithelial cells
Select all of the following ways adipose tissue will respond in the presence of insulin.
Increasing glycolysis. Fatty acids are stored as fat.
Which of the following factors increase the rate of diffusion across a membrane?
Increasing the solute concentration difference across the membrane Increasing the membrane area Increasing membrane permeability
Which of the following statements are true about the electromotive force?
Ions of opposite charge are attracted to one-another
Which of the following are not true of the equilibrium potential?
It depends on the permeability of 3 or more types of ions
Why is the flow speed (cm/s) in the right ventricle less than the left ventricle?
It has a larger cross-sectional area.
Which statements are TRUE of the axon hillock?
It initiates an action potential when its membrane potential exceeds a threshold.
Which of the following statements are true about osmolarity?
It is determined by the number of total solutes per volume of liquid
What role does bile play in fat absorption?
It keeps fat droplets from becoming large and impenetrable to enzymes
Which of the following correctly describe the function of hydrochloric acid in the stomach lumen?
It kills bacteria It converts pepsinogen to pepsin
Imagine that the blood within a vessel has a hydrostatic pressure of 30 mm Hg and a colloid osmotic pressure of 10 mm Hg. The surrounding interstitial fluid has a 25 mm Hg hydrostatic pressure and a zero colloid osmotic pressure. How is water likely to move?
It will move from surrounding tissue into the blood vessel
How would the equilibrium potential for potassium (ark+) change if the concentration of that ion increased outside of a cell?
It would increase
What would be the implications if your atria ceased to work?
Lower stroke volume Reduced contractility
You measure the blood pressure of an individual to be 150/90 mm Hg (systolic/ diastolic). If the mean arterial pressure (MAP) of someone with hypertension is generally above 100mm Hg. Determine this individual's MAP and whether they have hypertension
MAP is 110 mm Hg and they likely have hypertension
You measure the blood pressure of an individual to be 150 / 90 mm Hg (systolic / diastolic). If the mean arterial pressure (MAP) of someone with hypertension is generally above 100 mm Hg, determine this individual's MAP and whether they have hypertension.
MAP is 110 mm Hg and they likely have hypertension.
Which of the following interpretations of the data is most reasonable? (Pic 16)
Reduction in pressure are related to small vessel diameter
Imagine you were investigating the absorption of dipeptides (small proteins) by gut epithelia. You learn that this process depends process depends on both the concentration of intracellular ATP and extra cellular hydrogen ions. What is the most reasonable hypothesis for the transport across the apical cellular membrane?
Secondary active transport
Select all of the following that give conditions when excretion of a substance will occur.
Secreation is greater than reabsorption. Reabsorption is less than filtration and there is no secretion.
Select all of the following scenarios where no excretion of a substance would occur
Secretion and filtration combined are less than reabsorption Reabsorption is equal to filtration and there is no secretion
Which of the following are types of epithelial?
Secretory Protective Exchange Ciliated
What role(s) do osmoreceptors play in water balance?
Sensing osmolarity of blood. Release of vasopressin. As the integration center for maintaining water in the body.
Put the following steps of oxygen sensing by the glomus cells in the correct order.
Step 1: leading to a closure of K+ channels depolarising the membrane Step 2: triggering voltage-gated Ca2+ channels to open Step 3: causing an influx of Ca2+ triggers vesicles release Step 4: leading to neurotransmitter release to post-synaptic neuron
How does one measure the maximum force generated by a muscle fiber?
Stimulate the muscle with a series of action potentials. Load isometrically
The above image shows the anatomical range (green area) of the length-tension relationship for cardiac contractile cells. What are the functional benefits of the anatomical range?
Stops over-extension of cardiac muscle where force decreases Allows for increasing force generation as length increases within anatomical range
Select all of the following that are functions of the large intestine
Stores fences prior to defecation Absorbs water Houses a microbiome
Which of the following efferent pathways are only involuntary?
Sympathetic Parasympathetic Autonomic
Which parts of the brain are involved in the pathway of sensing and feeling reflexes?
Thalamus Somatic sensory cortex
What does homeostasis in body temperature suggest?
That your physiology tries to maintain body temperature against perturbation from activity
Select all of the following that are reasons cardiac muscle is resistant to fatigue.
The anatomic range of the heart is limited to avoid hyperextension. Action potentials from pacemaker cells are limited in the frequency at which they can fire.
What is the most important reason for why it requires energy to transport glucose across the apical surface of a digestive epithelial cell?
The concentration of glucose is greater within the cell than in the gut lumen.
Which of the following are NOT a property of a healthy heart?
The contractile cells operate on the ascending limb (i.e. left side) of the length-tension curve.
Select the appropriate function(s) of progesterone in the female reproductive system. (multiple answers possible)
The decrease in the late luteal phase triggers menses. Its increase during the late follicular phase and early luteal phase help to slow the growth and maintain the endometrium.
Which of the following statements are true about neurons?
The dendrites can integrate stimuli from inhibitory and excitatory synapses. Graded potentials occur within an axon inside of a myelinating schwann cell. The axon hillock serves as the spike-initiating zone because of the presence of voltage-gated channels.
Which of the following statements are FALSE?
The dendrites include voltage-gated K+ channels.
Which of the following statements are true about a population of uncharged particles in solution?
The edge of the population expand over time. The rate of expansion increases with temperature. The center of the population remains constant.
Choose the answer that best describes how the excretion rate changes as the concentration of a nutrient, like glucose, raises in the blood.
The excretion rate is zero at low concentrations. However, the excretion rate matches the glomerular filtration rate when the reabsorption pumps are saturated at higher concentrations.
Select which statement are not true of action potentials.
The inactivation gate reduces permeability in the voltage-gated K+ channel
Select with statement is not true about action potentials.
The inactivation gate reduces permeability in the voltage-gated K+ channel
Which statement are false?
The maximum depolarisation of an action potential depends on the graded potential at the spike-initiating zone. Action potentials travel in 2 directions routinely.
What parameters matter to how the state variable changes over time for the curve v? (Pic 8)
The set point Upper threshold The lower threshold
The rate of diffusion across a cell membrane will increase if
The solute is larger The membrane is thickened The solute is less lipid soluble Membrane surface area decreases
Our alveolar ventilation rate increase significantly when
There is a small increase in arterial PCO2
How can smooth muscle contract in multiple directions over a greater length than other types of muscles?
Thick and thin filaments are arranged in various directions. There are no sarcomeres in smooth muscle.
Choose all of the properties that correctly describe how valves prevent back-flow in the heart?
Valves mechanically prevent flow from occurring in both directions
Why does the partial pressure of oxygen in the arteries remain constant even as exercise intensity increases?
Ventilation rate increases More frequent contractions of diaphragm and abdominal muscles
How does the body maintain a constant partial pressure of oxygen in the arteries even as exercise intensity increases?
Ventilation rate increases.
In response to a hormone a cell up-regulates the expression of a membrane receptor by initiating protein synthesis. The hormone is probably
a steroid hormone
Using the above Wigger's diagram, match the corresponding event in the cardiac cycle to the correct Roman numeral. (Pic 27) i ii iii iv
a) AV valve closes b) semilunar valve open c) semilunar valve close d) AV valve opens
Why does a second stimulus during the relative refractory period have to be stronger to initiate an action potential? a) Because the threshold voltage is greater b) Because the membrane is permeable to Cl- c) Because the membrane is hyperpolarized.
a) Because the threshold voltage is greater c) Because the membrane is hyperpolarized.
The release of a neurotransmitter at a chemical synapse by a presynaptic cell includes which of the following components? a) Ca2+ ions b) regulatory (i.e., motor) proteins c) hormones d) Docking protein. e) vesicles
a) Ca2+ ions b) regulatory (i.e., motor) proteins d) Docking protein. e) vesicles
Which of the following factors increase the rate of diffusion across a membrane?a) Increasing the membrane area b)Increasing membrane thickness c) Increasing the solute concentration gradient across the membrane d) Increasing membrane permeability
a) Increasing the membrane area c) Increasing the solute concentration gradient across the membrane d) Increasing membrane permeability
What factors increase the propagation speed of an action potential? a) Myelination b) Axon diameter c) Permeability to Cl- ions
a) Myelination b) Axon diameter
How does temporal summation in the dendrites work for an excitatory chemical synapse? a)Na+ ions build in concentration from repeated activations b) Cl- ions build in concentration from repeated activations
a)Na+ ions build in concentration from repeated activations
What proteins bind epithelial cells together to provide a strong membrane and chemical barrier? a) tight junctions b) cross-junctions c) gap junctions d) desmosomes
a)tight junctions d)desmosomes
Select all that apply to allowing O2 transport through blood.
a. Dissolved proteins increasing oxygen solubility in blood. b. Erythrocytes containing heme groups increasing oxygen transport. c. Oxygen dissolving in the water within blood
Sally has unusually high blood pressure, which results in hydrostatic pressure of greater than 25 mm Hg in the venule end of her capillaries. This would generally decrease (answer 1), but allow (answer 2) to occur in her capillary beds.
absorption; filtration
What keeps females from ovulating during childhood?
estrogen and progesterone inhibit LH and FSH production
Choose the answer that correctly labels all three channels as well as their associated ion (pic 26) Channel i channel ii channel iii
funny (if) channel; voltage-gated calcium potassium leak channel
Based on the above plot which roman numerals correspond to times when the individual is exercising deep breathing?
the longest peak (iii)
Restrictive pulmonary pathologies are often associated with
the loss of ling compliance (stiffening)
a cellular response initiated by a G protein coupled receptor is not likely to involve
voltage gated ion channels
Which of the following statements are FALSE? a) The axon hillock functions as the spike-initiating zone because that is where the Na+ voltage-gated channels begin. b) The dendrites include voltage-gated K+ channels. c) A chemical synapse located close to the axon hillock has a better chance of generating an action potential than one far away.
b) The dendrites include voltage-gated K+ channels. c) A chemical synapse located close to the axon hillock has a better chance of generating an action potential than one far away.
Select all of the following TRUE statements.a) Adipose tissue has a crystalized matrix)All connective tissue includes cells.c)Ground substance may be a liquid.
b)All connective tissue includes cells .c)Ground substance may be a liquid.
Which of the following are TRUE about homeostasis in body temperature?a)That your body temperature never changes.b)That your physiology tries to maintain body temperature against perturbations from activity)that body temperature never remains consistent.
b)That your physiology tries to maintain body temperature against perturbations from activity
Select with statement is not true about action potentials. a) Repolarization is driven by K+ permeability. b)The inactivation gate reduces permeability in the voltage-gated K+ channel c) Voltage-gated channels for Na+ and K+ have the same threshold Vm. d) Depolarization would not happen if not for voltage-gated Na+ channels.
b)The inactivation gate reduces permeability in the voltage-gated K+ channel
What happens to the density of a population of particles in solution? a)The particles tend to more toward other particles b)The rate of expansion increases with temperature c)The edges of the population expand over time. d)The center of the population remains constant.
b)The rate of expansion increases with temperature c)The edges of the population expand over time. d)The center of the population remains constant.
The myosin head has which of the following properties?
A binding site for an ATP molecule. The ability to swivel during its power stroke. A binding site for an actin molecule.
Choose the answer that best describes what a central pattern generator (CPG) is and it's function.
A group of interneurons that produces spontaneous oscillatory patterns
Which of the following statements about the patellar-tendon reflex is false?
A region of the brainstem serves as an integration center
If the SA node fails, the heart rhythm will be generated by (answer 1) and heart rate will (answer 2)
AV node; decrease
What role do osmoreceptors within the hypothalamus play in water balance?
Act as the integration center in control loop for water retention Act as the sensory receptor in control loop of water retention Release vasopressin
Which would be a mechanism for stopping muscle contraction?
Administering a drug that disrupts the association between the dihydropyridine receptor (DHP) and ryanodine receptor (RyR).
As a pacemaker cells membrane potential gradually rises because I_f (funny) channels that allow (answer 1) , and once the membrane potential reaches -40mV it triggers (answer 2) channels to open, which allows (answer 3) and generate the action potential. Finally slow (answer 4) channels open, which allows only K+ to flow out.
Answer 1: I_f (funny) Answer 2: Na+ to flow in and K+ to flow out Answer 3: voltage-gated Ca2+ Answer 4: Ca2+ to flow inward Answer 5:voltage-gated K+ Answer 6: only K+ to flow out
Correctly match the anatomical feature to the glomerulus and Bowman's capsule. Glomerulus: answer 1 Bowman's capsule: answer 2
Answer 1: a web of porous capillaries Answer 2: low hydrostatic and colloid osmotic pressure where filtrate collects
When the parasympathetic nervous system releases (answer 1) it binds to (answer 2) cells which ultimately causes the heart rate to (answer3).
Answer 1: acetylcholine (ACh) Answer 2: autorhythmic cells Answer 3: decrease
Match the following salivary enzymes to their respective role in chemical digestion. Amylase: answer 1 Lipase: answer 2 Lysozyme: answer 3
Answer 1: breakdown starches Answer 2: break down fats Answer 3: kills bacteria
When your body get cold, (answer 1) in the skin send information to the (answer 2) which then triggers (answer 3) that prompt muscles throughout the body to involuntarily contract resulting in shivering and heat production.
Answer 1: cutaneous thermoreceptors Answer 2: hypothalamic thermoregulatory center Answer 3: somatic motor neurons
Select the correct order of responses your body will exhibit if visiting Joshua Tree National Park when the temperature is 38c (100F)
Answer 1: cutaneous thermoreceptors are excited Answer 2: signal travels through ascending tract of spinal cord Answer 3: hypothalamus integrates sensory info Answer 4: efferent pathway stimulates sympathetic nervous system Answer: vasodilation of blood vessels
What are the consequences of hyperglycemia (answer 1), and hypoglycemia (answer 2)?
Answer 1: damage to cells in the eyes and kidneys Answer 2: fatigue, or low energy
Match the following muscle components with their correct structure assignment. Sarcomere : (answer 1) Bicep muscles : (answer 2) Actin: (answer 3) Myofibrils : (answer 4) Muscle fiber : (answer 5)
Answer 1: protein complex Answer 2: organ Answer 3: protein Answer 4: organelle Answer 5: cell
You friend Mohammad is a sprinter on the Track team and interested in running faster. You suggest a training regiment that would increase his (answer 1) fiber types that have a (answer 2) concentration of mitochondria but generate (answer 3) tension and accelerations while running.
Answer 1: slow-twitch oxidative Answer 2: low Answer 3: high
Match the location in the nervous system to the correct aspect of sensing or control of ventilation. Dorsal ventilators Group: answer 1 Ventral ventilatory group: answer 2 Glomus cell: answer 3 Medulla chemoreceptors: answer 4 Pons: answer 5
Answer 1: stimulates muscles involved in inspiration Answer 2: stimulates muscles involved in expiration Answer 3: senses partial pressure of oxygen Answer 4: only senses partial pressure of carbon dioxide Oxygen 5: regulates the central pattern generator (CPG) governing ventilation
When running from a bear your (answer 1) nervous system is activated releasing (answer 2) which can bind to the (answer 3) receptors.
Answer 1: sympathetic Answer 2: norepinephrine (NE) Answer 3: alpha and beta 1
one of the treatments of sickle cell anemia (SCA) is to convert the adult hemoglobin to fetal hemoglobin. This implies that the mutation for SCA occurs in the gene for which globin?
B-isoform
How does the hormone arterial natriuretic peptides (ANP) trigger water excretion?
By causing vasodilation upstream of glomeruli leading to increased filtration rates
In what ways does norepinephrine act to increase blood pressure?
By reducing the duration of the pacemaker potential. By increasing contractility in the contractile cells By increasing peripheral resistance
How does the ascending limb of the loop of henle generate an osmolarity gradient in the interstitial fluid?
Through active transport of Na+ and Cl- out of filtrate and into the interstitial fluid Through facilitated diffusion of Na+ and Cl- out of filtrate and into the interstitial fluid
All connective tissue includes cells.
True
Joseph has a mutation that causes his hemoglobin to remain "fetal hemoglobin" for his whole life. At 40 mm Hg Po2, his Hb saturation level would resemble point (answer 1), and he would have a (answer 2) time exercising than someone with normal hemoglobin.
C; harder
Why is the force over v higher than over iii? (Pic 7)
Ca2+ is pumped into the SR slower than its release.
Which of the following tissues are not excitable?
Connective Epithelial
Which of the following describe aspects of the peripheral pathways for sensing body temperature?
Cutaneous thermoreceptors
At pint (answer 1), Hb has dropped off O2 at an exercising muscle and (answer 2) the pH would cause Hb to drop off more O2. Pic 24
D; decreasing
What is the most likely effect of drugs known as "calcium channel blockers"?
Decrease the force of cardiac contraction
What proteins bind epithelial cells together to provide a strong membrane and chemical barrier?
Desmosomes Tight junctions
Which of the following are properties of smooth muscle?
Does not have troponin Utilises calmodulin to facilitate thick and thin filament binding Can exhibit 'latching' to retain tension without need for ATP.
Smooth muscles in the GI tract have B2 (but not B1 or a) receptors. Which of the following affect digestion?
Epinephrine
Given that the glomerular filtration rate of a substance is 100 mg/min, the secretion rate is 20 mg/min and the reabsorption of this substance is 30 mg/min. What is the excretion rate of this substance from the body in mg/min?
Excretion = filtration - reabsorption + secretion Excretion = (100 mg/min) - (30 mg/min) + (20 mg/min) Excretion = 90 mg/min
The above plot illustrates the filtration and secretion rate of Creatinine as a function of the concentration in plasma. What do you expect the excretion rate to look like? (Pic 22)
Excretion rate will increase more rapidly at lower [creatinine] than at higher [creatinine] Excretion rate will always be higher than both secretion and filtration curves
Imagine you decrease [K+] in the interstitial fluid, but wanted to maintain the same resting membrane potential. What other changes could you make to maintain the resting potential?
Increase sodium in the interstitial fluid. Increase permeability to sodium
What are efferent action maybe recruited by the integration center for blood pressure to regulate high blood pressure?
Increase urination to excrete water
Based on the above graph of flow speed in the circulatory system, where does the maximum blood flow speed occur? (Pic 17)
Exiting the left ventricle
A carrier protein using secondary active transport hydrolyzes ATP to move molecules against their concentration gradient. T/F
F
Channel proteins are capable of active transport.
F
TRUE or FALSE: the distal tubule is where the maximal osmolarity of the filtrate within the collection duct of the nephron is set.
F
If this were a skeletal muscle, iii lasts about 1.5 seconds.
False
Select all of the following risks that are potential causes of Type 1 diabetes.
Few or no B cells in pancreas
By what factor would the rate of diffusion change if membrane thickness doubled?
Fick's law: rate of diffusion = (conc. difference * permeability *area)/ thickness 0.5
What are likely events to occur when a parasympathetic pathway is active?
Gastric motility increases
Select all of the following ways that correctly describe the timing of gametogenesis in males and/or females. (multiple answer possible)
Germ lines of both sexes undergo mitosis during embryonic development. Females experience menopause which stops egg production while males can continue sperm production until senescence or death occurs
Which of the following is/are chemical(s) in the blood that receptors in the medulla oblongata can directly sense?
H+ (protons)
How does summation in a single skeletal muscle fiber compare to a single twitch?
Increased tension Greater intracellular calcium
During exercise your body shunts blood to muscles and away from digestive processes to better allow for gas and nutrient exchange where the demand is high. How does your body accomplish this?
Vasoconstriction of arterioles leading to digestive system.
What occurs when alpha receptors in arterioles are stimulated by norepinephrine secreted by sympathetic neurons?
Vasoconstriction that results in increased blood pressure
The release of a neurotransmitter at a chemical synapse by a presynaptic cell includes which of the following components?
Vesicles Regulatory proteins Docking protein Ca2+ ions
Is the distance between a chemical synapse and the axon hillock important for whether an action potential is generated?
Yes, change in Vm in the dendrites depend on diffusion, which varies with distance.
The degeneration of myelin in axon can be debilitating because
a depolarizing graded potential doesn't reach the nodes of ranvier
You measure the linear flow rate of blood through the aorta of a fish to be 10 nn/s. You also find the flow rate of the average capillary to be 0.1 mm/a. If you know the cross-sectional area of the aorta is 1 mm^2 what is the cross-sectional area of all the capillaries in mm^2 (square mm)
Law of continuity: Ax in * U in = Ax out * U out Ax out = 1mm^2* ((10mm/s) / ( 0.1 mm/s)) Ax out = 100 mm^2
Select all of the following mechanisms for how norepinephrine (NE) directly affects contractile cardiac cells.
NE increases Ca2* release, which increases twitch tension NE shortens duration of activation
What is the primary reason that K+ has a higher concentration inside a cell than outside?
Na+ -K+ -ATPase
The flow rate of blood (L/s) reaches its maximum valve in the following region: (pic 18)
None of these are where the maximum occurs
True or False: The diastolic pressure in the arteries is much greater than the diastolic pressure in the left ventricle.
T
Why is a non-linear oxygen dissociation curve important for physiological function?
Oxygen is released in greater quantity where oxygen levels are lowest in the body. Delivery of more oxygen to tissues with greater oxygen consumption.
You are given yellow and blue balloons that are connected by a tube that you can not see through. To determine whether there is a valve within that tube and in what direction it opens, you perform that following excitements and make the following observations: 1) Sequeezing Balloon A (yellow) results in no volume of Balloon A while the volume of Balloon B decreases. 2) squeezing the Balloon B (blue) causes an increase in the volume of Balloon A while the volume of Balloon B decreases. Choose the diagram that beat represents the system you were given.
Pic 14 for answer
The bohr and haldane effecrs are related in that both (directly or indirectly) involve
Protons (hydrogen ions) CO2 The affinity of hemoglobin for O2 pH
Imagine someone has a cardiac output of 80 cm^3/s and aorta with a cross-sectional area of 4 cm^2. What would be the speed of flow (in cm/s) through the aorta?
Q=Su U=Q/S = 20 cm/s
What are the consequences of hyperventilation?
Raise in body's pH Increased partial pressure of O2 in the lungs and body
Where are the baroreceptors and integration center for the body's sensing and control of blood pressure homeostasis located?
Receptors are in the walls of arteries and the integration center is in the brainstem.
The inactivation gate reduces permeability in the voltage-gated K+ channel
The AP would propagate toward the cell body
As a wave of action potential travels from the atria to the ventricles, it is momentarily delayed as a result of slow conduction through what?
The AV node
How is it that the sinoatrial (SA) node controls the beat rate of the atrioventricular (AV) node?
The AV node has a lower autorhythmic frequency.
Select all the following that are true regarding the nodes and diners that drive heart contractions.
The AV node prompts ventricular contraction via the Purkinje fibers. Action potentials from internode divers stimulate the AV node
What would happen if Na+ -K+ ATPase stopped working in a digestive epithelial cell?
The Na+ - glucose carrier protein would decrease activity. [Na+] in the cell would begin to increase. [Glu] in the cell would begin to decrease.
The long lasting action potential in cardia muscles (contractile) cells prevents
The temporal summation of force
When animals die, their muscles become stiff within the first few hours, which is known as rigor Mortis. What factors contribute to rotor mortis?
There is little ATP in the cell. The myosin head cannot detach from the actin filament
How would the equilibrium potential for potassium (EK+) change if the concentration of that ion increased outside of a cell? a) it would increase b) it would decrease c) it would stay the same
a) it would increase
Which of the following is/are a type of epithelia? a) protective b) exchange c) ciliated d) secretory
a) protective b) exchange c) ciliated d) secretory
A cell containing 5M of glucose is placed in a solution containing 5M of glucose. After one hour the cell contains 7.5 M of glucose and the solution contains 2.5M of glucose. What process is likely to have occured?
active transport
Jerry is anemic. A trip to the doctor reveal low free iron levels in his plasma. The doctor observes that even when jerry actually consumes iron-rich food, he doesn't efficiently absorb the iron into the enterocytes of his digestive tract. This could be due to:
an inefficient divalent metal transporter
(answer 1) channels are critical for human hearing, where as (answer 2) channels respond to neurotransmitters, and voltage-gated channels are sensitive to changes in electrical activity across a membrane.
answer 1: Mechanically-gated answer 2: ligand-gated answer 3: voltage-gated
Voltage-gated Na+ channels entering an inactive state
are responsible for the absolute refractory period
What would happen if Na+ -K+ ATPase stopped working in a digestive epithelial cell? a) [K+] would decrease in the interstitial fluid b) The Na+ - glucose carrier protein would decrease activity. c) [Glu] in the cell would begin to decrease. d) [Na+] in the cell would begin to increase.
b) The Na+ - glucose carrier protein would decrease activity. c) [Glu] in the cell would begin to decrease. d) [Na+] in the cell would begin to increase.
Which of the following is not a component of inflammation?
blood vessel constriction
What would happen to an action potential (AP) if you strongly depolarized the membrane with a stimulating electrode near the axon terminal (i.e. at the distal end)? a) The AP would not propagate because it did not originate at the spike-initiating zone b) The AP would only travel toward the terminal c) The AP would propagate toward the cell body
c) The AP would propagate toward the cell body
During a contraction in smooth muscle, Ca2+ binds to
calmodulin
the force-velocity relationship of a muscle cell
can indicate the maximum shortening velocity of the muscle
What is the primary reason that K+ has a higher concentration inside a cell than outside? a) cotransporters b)the electromotive force c) K+pores (leak channels) d) Na+ -K+-ATPase
d) Na+ -K+-ATPase
to introduce a sympathetic response at a target cell, (answer 1) binds to (answer 2), receptors.
epinephrine, adrenergic (Beta- receptors)
All the end of expiration alveolar pressure will be
equal to atmospheric pressure
Mean Arterial Pressure can be decreased by
excreting more liquid from the body
Sandra has a mutation causing thrombin to be inactive,. This would affect her ability to make
fibrin
K+ ions play a critical role in excitable cells like neurons by
hyperpolarizing the cell during the falling phase of an action potential
Which panels correspond to positive feedback control? (Pic 10)
i (s-tau) iv
The nervous system can increase the force output of a muscle by
increasing the frequency of action potential sent to the neuromuscular functions
Voltage gated Ca2+ channels at the axon terminal...
it DOESN'T stabilize the membrane potential by moving into cell does not cause the graded potential that triggers an action potential does t maintain the concentration gradient for Ca2+ does not transport the recycled neurotransmitter back into the axon terminal
Which line corresponds to the threshold to the threshold potential? (Pic 1)
ix
a session of exercise where active tissues require (answer 1) oxygen than an individual's VO2max is considered (answer 2) exercise.
less; aerobic
Match the following mechanism for killing bacteria in the respective portion of the GI tract. Mouth stomach
lysozymes Low pH
How does the brain's response to estrogen and progesterone change due to ovulation?
ovulation causes both to inhibit production of GnRH as well as LH and FSH
The blood flowing through which of the following vessels has the highest oxygen concentration?
pulmonary vein
a rapid spinal reflex
regulates sensory afferent input to the spinal cord
Blood flowing through the superior vena cava next enters the
right atrium
Which of the following are types of epithelia?
secretory protective ciliated exchange
Select all the following processes that ONLY occur in gametogenesis. (multiple answers possible)
separation of replicated chromosome pairs in meiosis I separation of replicated chromosome pairs in meiosis II
Under normal, healthy conditions each heartbeat is initiated by a wave of depolarization initiated in the
sinoatrial node
Imagine you start being chased by a bear. What organs should have an increase in blood flow?
skeletal muscles lungs
Under parasympathetic stimulation, the pacemaker of autorhythmic cardiac cells (like the SA node) will
slow down, decreasing cardiac output
Which of the following are ONLY found within the central nervous system (CNS)?
spinal cord frontal cortex
Match the location in the nervous system to the correct aspect of sensing or control of ventilation. Dorsal Ventilatory Group: Ventral Ventilatory Group: Glomus Cell: Medulla Chemoreceptors: Pons:
stimulates muscles involved in inspiration stimulates muscles involved in expiration Senses partial pressure of oxygen Only senses partial pressure of carbon dioxide regulated the central governing ventilation
Increases in which of the following increase the rate of chemical diffusion?
temp
Select all of the following that apply to puberty in males. (multiple answer possible)
testosterone increases follicle stimulating hormone (FSH) increases
Endocrine patholgies can arise if any of the occur expect
the interaction between two hormones results in antagonism
How do birth control pills work? (multiple answer possible)
they increase estrogen and progesterone in the body they mimic conditions within the body of being pregnant
Differences in the sympathetic and parasympathetic nervous system include...
they use different neurotransmitters to interact with target cells
The role of ATP in a muscle contraction is to
transport calcium back into the sarcoplasmic reticulum
Slow twitch muscle fibers reach a fused tetanus in response to a lower frequency of action potentials at the neuromuscular junction compared to fast twitch fibers
true
Which of the following acts as the integration center in response to high concentrations of plasma glucose?
β cells in the pancreas.
Which of the following are TRUE regarding the membrane of the descending limb of the Loop of Henle?
Allows diffusion of urea that contributes to the osmotic concentration gradient of interstitial fluid. Includes aquaporins that allow water to leave and concentrate filtrate
Match the following characteristics to either Carrier, Channel membrane proteins, or both. Change conformation (Answer 1) Allow ions to leak (Answer 2) Traverse membrane (Answer 3)
Answer 1: Carrier proteins Answer 2: channel proteins Answer 3: both
Based on the above graph of linear flow speed in the circulatory system, where is the blood when the linear flow speech reaches its minimum? (Pic 19)
Capillary beds
Which of the following are driving forces for the motion of molecules across membranes?
Electromotive force Chemical diffusion Colloid osmotic pressure
What are the consequences of hypoventilation?
Lowering of blood pH
What is the most likely state of the activation gate of the K+ channels at time iv? (Pic 2)
Opened
What does line viii represent? (Pic 3)
The equilibrium potential for Na+
By what factor would the rate of diffusion across a membrane change if both its area and thickness doubled?
0
Choose the correct order of events in the myosin cycle.
1) myosin creates a cross-bridge with a G-actin binding site. 2) inorganic phosphate is released. 3) myosin pulls on the thin filament. 4) ADP is released. 5)myosin binds to ATP and releases from G-actin.
Glycolysis produces a total of (answer 1) ATP with a net production of (answer 2) ATP molecules and two pyruvate molecules per glucose.
1. 4 2. 2
Using point B as a reference, Hb has a reduced affinity for O2 at point (answer 1) and increased affinity at point (answer 2) Pic 24
A;C
You discover a new line of cardiac cells that have only β2 receptors. What efferent pathway would you expect to excite this type of cell?
Adrenal Sympathetic
Select of the following g that correctly describe how proteins are absorbed
Amino acids are absorbed through secondary active transport using the Na+ gradient Digestive enzymes help to break down large proteins Small peptides (having more than 3 amino acids) are absorbed through trancytosis.
Multiple type of (answer 1) tissue include collagen divers, which provide stiffness and elasticity. (Answer 2) tissue is largely composed of extra cellular components, such as ground substance, whereas transport (answer 3) tissue functions by transporting molecules through cells.
Answer 1: Connective Answer 2: connective Answer 3: Epithelial
Describe the following graphs based off their control mechanism. (Pic 9)
Answer 1: Feed Forward Answer 2: negative feedback Answer 3: positive feedback
Above is the electromyocardiogramtaken from a healthy patient. Match the appropriate section of the ECG to the action of the heart. (Pic 13) P : answer 1 Between P and Q: answer 2 Q-R-S complex: answer 3 Between S and T: answer 4 T to next P: answer 5
Answer 1: SA node depolarises atria Answer 2: atria contract Answer 3: depolarisation of atria and depolarisation of ventricles Answer 4: ventricles contract Answer 5: atria and ventricular diastole
Why does a second stimulus early in the relative refractory period have to be stronger to initiate an action potential?
Because the membrane is hyperpolarized Because the threshold voltage is greater
Select all of the following risks that are potential causes for type 2 diabetes
Being obese A non-active lifestyle
Select all of the following that correctly detail aerobic metabolism and glycolysis
Both glucose and fatty acids can be modified to be metabolized aerobically When little O2 is available, glycolysis results in lactic acid which lowers the pH of the tissue
Select all of the ways that CO2 is transported through the blood.
Directly transported in plasma Bound to hemoglobin (Hb) As carbonic acid dissolved in the blood as bicarbonate
Choose all that apply to muscle spindle organs.
Encode length of muscle. Can initiate stretch reflex pathways.
Your friend who works in a lab on campus is doing research that compares the contractile properties of cardiac and skeletal muscle. One day, she accidentally forgot to label a cell culture. What experiments could you suggest to determine whether the culture is cardiac or skeletal muscle?
Measure refractory period of muscle cell, because cardiac cells have longer refractory periods. Use high frequency stimulation to see if the muscle undergo tetanus because cardiac cells do not fuse twitches. Measure the duration of a muscle twitch, since cardiac muscles have a longer twitch duration.
Aortic and Carotid bodies are used to ...
Monitor the partial pressure of CO2 in our plasma
Using the above Hemoglobin-Oxygen Saturation curves explain why it is important to have a non-linear oxygen-dissociation curve.
More O2 is released in areas of the body where O2 concentrations are the lowest.
What factors or muscle properties affect the muscle's tension or force production?
Muscle length Contraction velocity Fiber type Thick and thin filament overlap
Select all of the following that are true about the sensing and integration centers that stimulate the release of atrial natriuretic peptides (ANP)?
Myocardial cells in the atria sense blood volume.
An adult ostrich has arterioles with the same diameter as the aorta in hatchlings (young ostrich), although the adult's arterioles has two time the length compared to the aorta of the hatchling. By what factor does the resistance to blood flow change from hatchling's aorta and to the adult's arterioles?
Need Poiseuille's Law: R= (L*n)/r^4 R=L =La/Ln = (2Ln)/(Ln) =2
How do positive feedback and negative feedback differ?
Negative feedback tends to oscillate around a set point.
Imagine a group of arterioles that posses alpha receptors but neither B1 nor B2 receptors. What is the effect of epinephrine on these arterioles?
Nothing
How can the clearance rate (change in excretion rate divided by the change in concentration of substance in plasma) be used to infer the glomerular filtration rate?
Once reabsorption pumps are saturated, only filtration rate impacts excretion rate
How does your body transport water across a membrane?
Osmosis By making the membrane permeable to water. By creating a difference in solute concentration across the membrane.
You take a trip to Denali National Park in Alaska and hike up 5,500 m in elevation toward the peak of Denali Mountain where the elevation is so high that atmospheric pressure is half that at sea level. If O2 comprises 21% of all particles in the atmosphere, what is the partial pressure of O2 at the highest point of your hike? Hint: pressure is 1 atm at sea level.
PO2 = 0.11 atm
Use the above image to correctly match the image with the appropriate scale of integration. (Pic 6)
i : system ii : organ iii : tissue iv: cell vi : protein complex
Refer this these figures to answer the following question. Note that i, ii, and iii are flow charts of control systems and iv and v show changes in state variables over time. Which panels correspond to the control of energy balance? Pic 25
ii and v
Match the Roman numerals in the above image to the correct anatomical structure of the heart. (Pic 15)
ii: right atrium iii : right ventricle iv: pulmonary artery v: aorta vi: left ventricle vii: left atrium viii: pulmonary vein ix: semilunar valves x: AV valves
Chronic exposure to endurance exercise will
increase the ability to deliver oxygen to active muscle tissue
You travel from Irvine (sea level) to Denver (1.6km above sea level). The significant drop in ambient PO2 cases a reduction alveolar and arterial PO2. To counteract this drop in oxygen availability you body can immediately respond by
increasing tidal volume
a metabolic disorder called hypokalemia results in abnormally low K+ concentration is extracellular fluid. This condition will
make the resting membrane potential more negative
In which of the following area(s) of the kidney are nephrons located?
medula and cortex
Choose the level(s) of biological organization that pertain to physiology.
molecules and tissues
