1. Control a. In a negative feedback system, a is a device that measures the current value of the.

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1 Quiz Questions Week #1 1. Control a. In a negative feedback system, a is a device that measures the current value of the. b. Define an effector? c. What does it mean when a negative feedback system is in steady state? 2. Calcium Homeostasis a. Parathyroid hormone increases extracellular plasma calcium levels through a variety of mechanisms. Please list/describe two. b. What effect does 1,25-(OH) 2 Vitamin D have upon extracellular plasma calcium levels? How is this effect achieved? c. During parturition, smooth muscle contractions are designed to get increasingly forceful. To accomplish this, the hormone oxytocin plays a pivotal role. What component of a positive feedback system is oxytocin? What body system serves as the amplifier? 3. Ion Transport a. An impermeable membrane separates two chambers containing one liter of solution at 1 PM. The left chamber contains 2M KCl and 1 M NaCl. The right chamber contains 1M KCl and 2 M NaCl. At 2 PM, the membrane is made permeable to Na+ ONLY. At 4 PM, the membrane is then made permeable to Na+ and Cl- ions. Which of the following would you see? A. Flux of Cl- ions to the right at 5 PM B. Flux of Cl- ions to the left at 5 PM C. Flux of K+ ions to the right at 3 PM D. Flux of K+ ions to the left at 3 PM E. A and C F. A and D b. An impermeable membrane separates two chambers containing one liter of solution at 1 PM. The left chamber contains 2M KCl and 1 M NaCl. The right chamber contains 1M KCl and 2 M NaCl. At 2 PM, the membrane is made permeable to K+ ONLY. At 4 PM, the membrane is then made permeable to K+ and Cl- ions. Which of the following would you see? A. Flux of Cl- ions to the right at 5 PM B. Flux of Cl- ions to the left at 5 PM C. Flux of K+ ions to the right at 3 PM D. Flux of K+ ions to the left at 3 PM E. A and C F. A and D

2 c. An impermeable membrane separates two chambers containing one liter of solution at 1 PM. The left chamber contains 1 M KCl and 2 M NaCl. The right chamber contains 2 M KCl and 1 M NaCl. At 2 PM, the membrane is made permeable to Na+ ONLY. At 4 PM, the membrane is then made permeable to Na+ and Cl- ions. Which of the following would you see? A. Flux of Cl- ions to the right at 5 PM B. Flux of Cl- ions to the left at 5 PM C. Flux of K+ ions to the right at 3 PM D. Flux of K+ ions to the left at 3 PM E. A and C F. A and D d. During osmosis, a. The solution having the higher concentration of dissolved substances in water is made more dilute b. There is no movement of liquid across the membrane c. There is always a flow of dissolved substances along with water e. During diffusion of ions across a plasma membrane, a. ATP molecules are utilized b. The ions move from a region of low ionic concentration to a region of high ionic concentration c. The specific ion can move through an open channel of a membrane-spanning protein that is permeable to that ion. f. When a viable red blood cell is placed into distilled (pure) water, a. Ions will traffic through the plasma membrane via membrane-spanning protein channels. b. The ATP pool in the cell is not large enough to provide energy to allow for all the ions that need to passage out of the cell. c. The cell will lyse d. A and B e. A and C

3 Jesse Lugus Quiz questions, week 2: Transport & Neuro 1. (2 points)which is NOT a feature of Simple Diffusion? a. Passive process b. Lipid soluble molecules can move using it c. Steroid hormones (estrogen, testosterone) use it 2. (2 points)which of the following is NOT a feature of a uniporter? a. Transported molecules move in one direction only b. Transport never requires a conformational change of the transporter c. Molecules can move against their concentration gradient 3. (2 points)which of the following is true for secondary active transport? a. ATP is used directly b. An ATP-generated concentration gradient is required for the Na,K-ATPase c. Only one molecule can be moved 4. (6 points) The concept of resting membrane potential is huge. Without RMP, the idea of an excitatory cell is nearly impossible. Given that the value of RMP is 70 mv for a prototypic neuron, how could you make this value increase? Please indicate at least one way that involves modification of PM-spanning protein function. - increase RMP by decreasing [K+]in. do this by altering K+ ion channel such that K+ flux out of cell is increased or by altering Na,K-ATPase in some way that decreases import of K+. Can also drastically alter Na+ balances by changing gradient such that [Na+] out is drastically, drastically decreased (or vice versa). 5. (6 points) The concept of resting membrane potential is huge. Without RMP, the idea of an excitatory cell is nearly impossible. Given that the value of RMP is 70 mv for a prototypic neuron, how could you make this value decrease? Please indicate at least one way that involves modification of PM-spanning protein function. - decrease RMP by increasing [K+]in. do this by blocking K+ ion channel such that K+ flux out of cell is decreased or by altering Na,K-ATPase in some way that increases import of K+. Can also drastically alter Na+ balances by changing gradient such that [Na+]in is drastically, drastically, increased or vice versa).

4 6. (6 points)the concept of resting membrane potential is huge. Without RMP, the idea of an excitatory cell is nearly impossible. Please explain why RMP is negative. Be sure to indicate the chief ion that accounts for this negativity as well as the two transporters that act to maintain a concentration gradient as well as to allow for movement for/during and action potential. -RMP is (-) because K+ ions are the major intracellular ion and using them in the nernst equation gives a RMP of (~) 60 mv. The Na,K-ATPase helps keep K+(in) high and the ion-gated K+ channel allows for the flux of ions during an AP 7. (2 points)tetrodotoxin (TTX) will interfere with: a. Generation of action potentials b. Maintenance of the Na+ gradient that exists between the intra- and extracellular environment c. Maintenance of the K+ gradient that exists between the intra- and extracellular environment d. A and B e. A and C 8. (2 points) Tetraethylammonium (TEA) will interfere with: a. Generation of action potentials b. Maintenance of the Na+ gradient that exists between the intra- and extracellular environment c. Maintenance of the K+ gradient that exists between the intra- and extracellular environment d. A and B e. A and C 9. (2 points) The Na,K-ATPase is responsible for: a. Pumping Na+ and K+ out b. Pumping Na+ and K+ out c. Pumping Na+ in and K+ out d. Pumping ATP and Na+ in e. Pumping ATP and K+ in f. None of the above

5 Jesse Lugus Week #3 Quiz Questions- Neuro/Synapse 1. Please list the two broad categories (with respect to AP generation) of ligand-gated channels. 2. What are the two mechanisms that affect the opening of ion channels that you would find on a post-synaptic neuron? 3. In a synapse, if the presynaptic neuron is a sensory neuron, what kind of neuron would be the post-synaptic neuron? (two possible right answers, only give one). 4. In a synapse, if the post-synaptic neuron is a motor neuron, what kind of neuron would be the presynaptic neuron? (two possible right answers, only give one). 5. In the central nervous system, threshold is higher than the peak of excitatory postsynaptic potential. To overcome this, what process must occur such that membrane voltage exceeds threshold? 6. Summation is the process that occurs such that membrane voltage exceeds threshold in a postsynaptic neuron in the CNS. Please name and describe the two ways that summation occurs. 7. Please draw the voltage change that occurs in a postsynaptic cell in the CNS if a chloride channel opens up in response to a presynaptic stimulus. For this question, assume standard RMP of 70 mv, a threshold of 55 mv and an E cl of 80 mv. 8. Please draw the voltage change that occurs in a postsynaptic cell in the CNS if a chloride channel opens up in response to a presynaptic stimulus. For this question, assume standard RMP of 70 mv, a threshold of 55 mv and an E cl of 70 mv. 9. Please draw the voltage change that occurs in a postsynaptic cell in the CNS if a chloride channel opens up in response to a presynaptic stimulus. For this question, assume standard RMP of 70 mv, a threshold of 55 mv and an E cl of 60 mv. 10. What is the ligand for a GABA A ion Channel? a. GABA b. AMP c. K+ d. Helium e. Cl- 11. What is the ligand for a GABA B ion Channel? a. GABA b. AMP c. K+ d. Helium e. Cl-

6 12. What passes through a GABA A ion Channel? a. GABA b. AMP c. K+ d. Helium e. Cl- 13. What are the three types of muscle? Which requires neural input for contraction? 14. During a shortening contraction, which of the following shorten in length? a. H-zone b. A-band c. I-band d. A and C e. A and B 15. During a shortening contraction, which of the following does not change in length? a. H-zone b. A-Band c. I-Band d. A and C e. A and B

7 Jesse Lugus Week #4 Quiz Questions- Muscle/circulation 1. In the sarcomere, levels of Ca 2+ will allow myosin heads to bind actin 2. In the sarcomere, levels of Ca 2+ will interfere with the binding of myosin heads to actin 3. When the levels of Ca 2+ in the sarcomere are low, what is the protein that physically interferes with the interaction between actin and myosin? 4. Which molecule would expect to see bound to a myosin molecule that is not attached to an actin filament, ATP or ADP+Pi? (Circle your choice) 5. Which molecule would expect to see bound to a myosin molecule that is attached to an actin filament, ATP or ADP+Pi? (Circle your choice) 6. Imagine that you are incredibly, incredibly small. You are inside a skeletal muscle and you are low on energy so you decide to take ATP for your own greedy self, thereby depleteing the ATP levels in the sarcomere. Will your thievery interfere with the GENERATION of actin-myosin cross-bridges or the RELAXATION of the crossbridges? (Circle your choice) 7. Heart valves close in response to: a. Electrical stimulus b. Ca2+ flux c. You getting shot down by that guy/girl you have had the hots for since Freshman year d. Force 8. Arteries carry blood (From/Along/To/Inside) the heart. 9. Veins carry blood (From/Along/To/Inside) the heart. 10. Imagine that one night while you were sleeping, your heart left your body and went out drinking. After a few too many vodka-tonics, it had some words with a mean, cirrhotic liver and ended up getting whupped in a bar fight. The next morning, your heart s SA Node looks real bad. In fact, it s not functioning properly. Without a properly functioning SA node, how will your heart behave? 11. Imagine that one night while you were sleeping, your heart left your body and went out drinking. After a few too many vodka-tonics, it had some words with a mean, cirrhotic liver and ended up getting whupped in a bar fight. The next morning, your heart s AV Node looks real bad. In fact, it s not functioning properly. What would this do to propagation of the electrical signals in your heart? 12. Imagine that one night while you were sleeping, your heart left your body and went out drinking. After a few too many vodka-tonics it blacked out. Being the immature, irresponsible organ it is, the next morning you realize that it lost it s SA node (likely somewhere in E. St. Louis). Without it s SA Node, how will your heart behave, maturity aside?

8 During an action potential in a ventricular muscle fiber, which of the following is primarily responsible for the initial depolarization (i.e., from RMP of 70 mv to ~0 mv)? a. F-channel b. Voltage-gated Na+ channel c. Voltage-gated K+ channel d. Voltage-gated Ca 2+ channel e. The English Channel f. None of the above 13. During an action potential in a ventricular muscle fiber, which of the following is primarily responsible for the prolonged plateau at ~0 mv? a. F-channel b. Voltage-gated Na+ channel c. Voltage-gated Ca 2+ channel d. KSDK- Channel During an action potential in a SA node cell, which of the following is primarily responsible for the pacemaker potential? a. F-channel b. Voltage-gated Na+ channel c. Voltage-gated K+ channel d. Voltage-gated Ca 2+ channel e. The Discovery channel f. None of the above 15. The nerves from the carotid artery baroreceptors are cut. Their axonal stumps are still connected to the central nervous system and are electrically stimulated at a high rate. This stimulation will a. Cause an increase in sympathetic discharge to the heart b. Cause a decrease in arteriole diameter c. Cause a decrease in blood pressure 16. The nerves from the carotid artery baroreceptors are cut. Their axonal stumps are still connected to the central nervous system and are electrically stimulated at a very low rate. This stimulation will a. Cause a decrease in sympathetic discharge to the heart b. Cause an increase in arteriole diameter c. Cause a decrease in blood pressure 17. The nerves from the carotid artery baroreceptors are cut. Their axonal stumps are still connected to the central nervous system and are electrically stimulated at a high rate. This stimulation will a. Cause an increase in sympathetic discharge to the heart b. Cause a decrease in arteriole diameter c. Cause an increase in blood pressure

9 Jesse Lugus Respiration Questions: Week Two compartments of equal volume of physiological saline are separated by a membrane permeable only to oxygen. At 2 AM equal amounts of oxygen are dissolved into both the left and the right compartments. At 3 AM, healthy red blood cells are prepared so that they contain no oxygen. At 3:05 AM, these cells are placed into the right compartment. At 4 AM additional oxygen is added to the left compartment only. Ignore any effects of cellular respiration. a. At 3:30 AM the amount of oxygen in the left compartment will be higher than it was at 2:30 AM. b. At 4:30 Am the amount of oxygen bound to hemoglobin in the red blood cells will be larger than or equal to the amount at 3:30 AM. c. At 3:30 AM the amount of extracellular oxygen in the right compartment will be higher than it was at 2:30 AM d. All of the Above e. None of the Above 2. Two compartments of equal volume of physiological saline are separated by a membrane permeable only to oxygen. At 2 AM equal amounts of oxygen are dissolved into both the left and the right compartments. At 3 AM, healthy red blood cells are prepared so that they contain no oxygen. At 3:05 AM, these cells are placed into the right compartment. At 4 AM additional oxygen is added to the left compartment only. Ignore any effects of cellular respiration. a. At 3:30 AM the amount of oxygen in the left compartment will be higher than it was at 2:30 AM. b. At 4:30 Am the amount of oxygen bound to hemoglobin in the red blood cells will be less than the amount at 3:30 AM. c. At 3:30 AM the amount of extracellular oxygen in the right compartment will be higher than it was at 2:30 AM d. All of the Above e. None of the Above 3. Two compartments of equal volume of physiological saline are separated by a membrane permeable only to oxygen. At 2 AM equal amounts of oxygen are dissolved into both the left and the right compartments. At 3 AM, healthy red blood cells are prepared so that they contain no oxygen. At 3:05 AM, these cells are placed into the right compartment. At 4 AM additional oxygen is added to the left compartment only. Ignore any effects of cellular respiration. a. At 3:30 AM the amount of oxygen in the left compartment will be less than it was at 2:30 AM. b. At 4:30 Am the amount of oxygen bound to hemoglobin in the red blood cells will be larger than or equal to the amount at 3:30 AM. c. At 3:30 AM the amount of extracellular oxygen in the right compartment will be higher than it was at 2:30 AM d. A and C e. A and B f. B and C g. None of the Above 4. Which of the following serves as an actuating signal, or as part of an actuating signal, in a negative feedback system? a. Blood plasma levels of Parathyroid hormone (PTH) receptors b. Blood plasma levels of oxytocin c. Cell-surface calcium receptors of parathyroid gland cells

10 5. Which of the following serves as an actuating signal, or as part of an actuating signal, in a negative feedback system? a. Blood plasma levels of Parathyroid hormone (PTH) b. Blood plasma levels of oxytocin c. Cell-surface calcium receptors of parathyroid gland cells 6. Which of the following serves as a sensor, or part of a sensor, that functions in a negative feedback system? a. S5-S6 helices of the voltage-gated Na+ channel in the diaphragm b. Alveoli of the lungs c. Osmoreceptors in the hypothalamus 7. Which of the following contribute(s) to the movement of air into/out of the lungs during ventilation? a. Contraction of smooth muscles in the lung b. Contraction of skeletal muscles c. Changes in air pressure between the atmosphere and your lungs d. A and C e. A and B f. B and C g. All of the above h. None of the above 8. Which of the below does NOT occur during the five steps of respiration? a. Air is exchanged between the atmosphere and alveoli b. Cells utilize O 2 and produce CO 2 as waste during ATP production c. Exchange of H+ ions between lung alveoli and body cells 9. The rhythm of the rate of respiration is controlled by which of the following? a. Glutamatergic interneurons in the brainstem b. Muscarinic interneurons in the brainstem c. Glycinergic interneurons in the lung d. Acetylcholinergic interneurons in skeletal muscle f. All of the above 10. The nephron has a number of responsibilities. Please indicate which of the following events are correlated to the proper sublocation within a nephron. a. Filtration- Tubules and loop b. Reabsorbtion- Bowman s capsule c. Tubular secretion- Tubules and loop

11 11. True or False: the tubular fluid in the capsule is an ultrafiltrate of blood. 12. True or False: Input to the nephron is from the collecting duct.