(Here you will find answer keys for homework or quizzes as well as unedited responses on exams from your classmates)
1. The K ion channel is an example of how molecules are transferred across the phospholipid bilayer by the process of
a. simple diffusion
b. facilitated transport
c. secondary active transport
d. primary active transport
2. If you placed one of your cheek cells (given: The ICF = 170 mM NaCl ) in a solution of 300 mM glucose, and you assume neither compound could permeate the PL bilayer, through the process of osmosis your cell would
c. be happy as a clam (normal cell volume)
d. cannot determine by the provided information
3. The Na/K ATPase pump uses a method called __________________ __________________
or successive phosphorylation/dephosphorylation cycles to change its configuration and pump ions against their concentration gradients.
ANSWER: Molecular Peristalsis
4. T or F (please circle)
If a cell has an electrical disturbance of at least 30 mV, it will always fire an action potential because of the ALL-or-NONE principle.
5. Which of the following physiological processes requires no ATP expenditure?
d. facilitated diffusion
e. two of the above
6. Which of the following organic molecules would be classified as a protein?
a. molecules that are formed from dehydration reactions
b. molecules that contain free fatty acids
c. molecules that are produced from peptide bond formations
g. ketone bodies
7. If a cell had the following ionic concentrations and permeabilities, about at what voltage would you predict an action potential would change polarity (peak of the action potential spike)?
HINT: You can decide whether to use Nernst or Goldman.
PK = 10
PNa = 10,000
Assume mammalian temperature of 37 degrees.
[K+]o = 40 mM
[K+]i = 365 mM
[Na+]o = 420 mM
[Na+]i = 65 mM
Please show all calculations. Answer: ______________________________
ANSWER: You can use either Nernst or Goldman, but of course the former is less time consuming.
ENa = 60 log (420/65) = 49 mV
Em = 60 log[ [(10,000)420 + 10(40)]/[(10,000)65 + 10(365)] = 49 mV
8. If the resting potential of the cell in #7 was -85 mV, at what voltage would this action potential begin to fire fully? HINT: Threshold.
Please show all calculations. Answer: _________________________________
ANSWER: Th = 0.15 (Amplitude)
Amplitude = -85 mV to 49 mV = a delta of 134 mV
134 * 0.15 = 20 mV
If the resting potential is -85 mV and you have to calculate the voltage at which the AP would fire fully, then add 20 mV to -85 mV = -65 mV
9. Write one sentence describing the importance of the phospholipid bilayer for the physiologist =
ANSWER: Many things here!
10. T or F (please circle)
According to Fick’s Law of Diffusion, the diffusion rate or flux is greatest when the molecule to be transported has a high molecular weight and has to traverse a large cross-sectional area.
11. If an action potential (AP) reaches threshold, where in the neuron will the AP “spike” be initiated?
a. the dendrite
b. the soma
c. the axon hillock
d. the synaptic terminals
e. the sodium/potassium ATPase pump
EXAM 1 Answer Key
43) a, T
44) b, F
45) a, T
46) b, F
47) a, T
48) b, F
49) a, T
50) b, F
51) b, F
52) a, T
53) b, F
54) b, F
55) a, T
56) a, T
57) a, T
58) a, T
59) a, T
60) a, T
61) b, F
62) b, F
63) b, F
1. Which of the following types of muscles are striated and involuntary?
d. b and c
e. a and b
f. none of the above
2. A single muscle CELL is known as
a. a sarcomere
b. a myofibril
c. one actin and one myosin filament
d. a motor unit
e. a muscle fiber
3. Action potentials move perpendicular to the muscle fibers by entering the transverse tubules that are located where along the sarcomere?
a. A band
b. Z band
c. M band
d. I band
e. Z and I bands
f. A and I bands
4. Which of the following “contractile proteins” functions to block the thick filament from accessing a binding site to form a cross bridge but does not physically bind calcium?
5. In relation to skeletal muscle mechanics, during which phase of the twitch would calsequestrin have its highest activity?
a. latency period
6. T or F (please circle)
The white matter is responsible for integrating reflex activity using polysynaptic and monosynaptic connections of afferent and efferent neurons, respectively.
7. Which of the following does not mediate or assist in smooth muscle contraction of your arteries?
a. inositol 1,4,5-trisphosphate
b. dense bodies
d. sarcoplasmic reticulum
e. ALL are helpful in smooth muscle contraction
8. During a skeletal muscle contraction, the length of the sarcomere shortens due to a decrease in size of ALL but which band?
a. A band
b. Z band
c. H band
d. I band
e. All of the above will shorten
9. If the cross-bridge cycle was in a stage where there was no calcium, the orientation of the myosin head was at 90 degrees in relation to the tail of the molecule, and there was ATP available, then the muscle would be in which stage of contraction?
a. the actin and myosin would be touching each other
b. it would be in the power stroke
c. actin and myosin would be detached and ATP would undergo hydrolysis
d. it would be in a rigor mortis locked complex
10. Which of the following activities is performed principally by the somatic nervous system?
a. beating of your heart
b. bowel movements
c. running up the stairs
11. Which portion of the spinal column has emerging spinal nerves that would innervate the chest region?
e. dorsal root ganglion
1. T or F (please circle) The Law of LaPlace states that the stress on a vessel will decrease when the width of the smooth muscle running circumferentially around the blood vessel increases.
2. Which of the following type of muscle is neurogenic and has economical cross-bridge cycling due to phosphorylation of the myosin tail?
a. pacemaker activity
b. slow wave potentials
c. single-unit smooth
d. multi-unit smooth
3. If blood was entering your RV too slowly, it would be attributed to a defect in which valve?
d. pulmonary semilunar
e. aortic semilunar
4. When blood moves from the left atria to the left ventricle
a. it passed through the pulmonary semilunar
b. the timing would be in register with the T wave
c. the blood would be deoxygenated
d. one would hear the S1 on the phonocardiogram
5. What is stimulated to contract by an increase in oxygen that is taken in at the baby’s first breath and is only seen as a remnant or ligament in the adult?
ANSWER: ductus arteriosis
6. T or F (please circle)
Veins carry the greatest distribution of circulating blood flow.
7. Smooth muscle uses which structure for contraction because it lacks sacromeres and Z lines?
a. intermediate filaments
b. dense bodies
d. troponin-Ca complex
e. phosphorylation of actin globules
8. Which of the following exemplifies cardiac muscle?
a. it lacks troponin
b. it lacks T-tubules
c. it is unstriated
d. it is neurogenic not myogenic
e. it uses both pools of calcium (from SR and ECF)
9. If a physician was trying to hear the closure of the pulmonary semilunar they would
a. be seeking an event that is aligned with the timing of the QRS spectrum
b. be positioning the stethoscope at the left of the heart apex
c. be seeking an event that occurs at the same time as the T wave
d. be seeking an event that occurs when the atria repolarize
e. find that the RV would be in systole
10. If you measured your heart beat five times in six seconds, then you would be
d. undergoing atrial flutter
e. susceptible to first degree AV block
11. Dr. D and a student, who will remain nameless, bump into each other at the Ocala Publix health monitoring machine early Sunday morning. Dr. D ran there from her lab on campus (to practice for her hike in the Grand Canyon, of course!) while the student had just crawled out of bed, and just really wanted to get some breakfast, but then remembered the assignment. Compute the difference in cardiac output between the two. Assume they both have a 70 ml volume coming out of their LV with every beat. Show all your work.
Dr. D. = 120 bpm
student = 65 bpm ANSWER: CO = SV x CR = 70 ml/beat x 120 beats/min = 8,400 ml/min
70 ml/beat x 65 beats/min = 4,550 ml/min
8,400 ml/min – 4,550 ml/min = 3850 ml/min = 3.9 L/min
12. EXTRA EXTRA CREDIT - If you did your bp homework!!!
1 pt. What is your bp reading? _____________ Using that value, what is your pulse pressure or PP? ____________________ mm Hg
1 pt. Using your computed PP, what is your mean arterial pressure or map? _____________ mm Hg
(Show all your calculations here - )
Mine was 106/58, therefore PP = 106-58 = 48
Then MAP = diastolic + 1/3 (PP) = 58 + (1/3)48 = 74 mm Hg
Exam 2 Answer Key
1. Which of the following muscle would be used with passive exhalation and not recruited for only a forced exhalation requiring energy?
a. internal intercostal
b. external abdominal oblique
c. transversus abdominus
d. rectus abdominus
2. When carbon dioxide associates with the respiratory pigment hemoglobin it is called -
3. When sampling the new planet Vena, scientists found that the total atmospheric pressure was 600 mm Hg and that animals used the gas Tx to breath. Calculate the partial pressure for Tx on Vena if it comprises 12% of the atmosphere on the planet? ____________________________
ANSWER: PP = % gas x psi; PP Tx = .12 x 600 = 72 mm Hg
4. Which of the following cellular environments would promote an earlier dissociation of oxygen from hemoglobin (dump O2 sooner)?
b. severe body heat loss
c. any condition inducing a left Bohr shift
e. a blood transfusion
5. Carbon dioxide is transported back to the lungs in several forms, the most predominant being
a. free, dissolved carbon dioxide
e. carbonic acid
6. Write out the carbonic anhydrase shift equation, including the enzyme that is involved =
ANSWER: CO2 + H2O >>><<< H2CO3>>>><<<< H+ + HCO3-
Carbonic anhydrase – enzyme
7. If your patient weighed 100 kg and was bringing in 800 ml of fresh air with each breathe, what should be the level of vital capacity measured if their ERV was 1.4 L and their IRV was 3 L?
(Show all work)
ANSWER: VC = ERV + IRV + TV; TV = Va + Vd.
Vd = 2 x 100 kg = 200 ml
TV = 800 ml + 200 ml = 1L
VC = 1.4 + 1 + 3 = 5.4L
8. T or F (please circle)
Air falls down pressure gradients during inspiration and expiration according to Haldene’s Law.
9. If you had a TLC of 8L and the standard 1L reserve as your RV, could a VC be calculated?
If yes, VC = _______________________________ If not, what variables are you lacking to make the calculation? ________________________________________
TLC = VC + RV
8 -1 = 7 L
10. Which lung disease can be attributed to the constriction of the bronchioles, causes air trapping, has an elevated RV and normal TLC and a reduced VC, and can be reversible by treating with drugs that cause vasodilation?
b. pulmonary fibrosis
c. not a lung disease, but too little exercise
e. not a lung disease, but attributed to reduced elasticity of old age
11. How many molecules of oxygen bind Hb when it is fully saturated?
1. Which of the following would you not find in the ultrafiltrate of the pct?
d. free cellular material
2. A patient with the following condition would produce the most urine?
a. kidney stones
d. extensive burns
3. If you consumed a snicker’s bars and your blood contained 300 mg/100 ml (3 mg/ml) of glucose and your current GFR was 150 ml/min, given the known Tm of 375 mg/min, how much glucose will spill over into your urine every minute?
(Show your calculations)
4. Which of the following renal functions require no energy?
a. countercurrent multiplication
b. K secretion in the dct
c. sodium reabsorption in the pct
d. glomerular filtration
5. Water reabsorption is directly facilitated by
6. ADH is released from the _____________________ __________________while aldosterone is released from the ___________ __________, yet both function similarly to bring low blood pressure and volume back to homeostatic checkpoint.
7. If you are retaining too much water and want to purge your bloatedness you could
a. increase angiotensin II
b. stimulate your granular cells
c. increase ANP
d. enhance ACE
e. block Na/K ATPase pumps in your dct
f. two of the above
8. Which of the following situations would require renal dialysis?
a. athletic pseudonephritis
c. uremic blood, high K
e. production of less than 500 ml urine
9. T or F (please circle) Humans have a larger proportion of juxtamedullary nephrons over that of cortical nephrons with surrounding peritubular capillaries and long loops of Henle for efficient urine production.
10. T or F (please circle) All sections of the nephron are under strict hormonal control with exception of the loop of Henle.
11. Which renal acting hormone acts as a derepressor in the nucleus to create new protein synthesis of Na/K ATPase pumps?
3 mg/ml x 150 ml/min = 450 mg/min – 357 mg/min = 75 mg/min into urine
posterior pituitary, adrenal cortex
Exam 3 Answer Key:
1. Which of the following motilities only occurs in the stomach?
b. mass movement
d. receptive relaxation
2. Which of the following would DECREASE movement of chyme out of the stomach?
a. lots of fluid in the stomach body
b. increased parasympathetic stimulation
c. low fat diet
d. fear to take your GRE
e. your brother wreaking your car (and no, you are not afraid of his safety!)
3. Which cell type produces the enzyme to DIGEST fat?
a. parietal cells
b. surface epithelial cells
c. acinar cells
d. duct cells
4. Which is NOT correct concerning HCl in the stomach?
a. it is partially derived by the carbonic anhydrase shift equation in parietal cells
b. it cleaves pepsinogen to generate pepsin
c. it is released from the surface epithelial cells to prevent peptic ulcers
d. the hormone gastrin from the PGA areas can increase its secretion
e. it can kill microorganisms in your food
5, 6, 7, and 8. Fill in the following empty boxes in the table below (example is provided for the first row):
Interstitial Cells of Leydig in the Male Testes
Increases uterine contractility
GHRH (GROWTH HORMONE RELEASING HORMONE)
Release of GH
9. T or F (Please circle)
A mature ovum is arrested in the first meiotic stage of division and is unfertilized (sperm entry has not occurred).
10. In the male reproductive tract, which structure is responsible for alkaline secretions and clotting enzymes to increase the probability of successful fertilization?
B. seminal vesicle
D. prostate gland
E. bulbourethral gland
11. Which medical ailment is attributed to the large intestine?
a. gall stones