Examination Paper of Physiology
I. Explain the following terms in English ( 25 points, 2.5 points each ).
1. Negative feedback
2. Homeostasis
3. Resting potential
4. Blood coagulation
5. Stroke volume
6. Oxygen dissociation curve
7. Digestion
8. Respiratory quotient
9. Dark adaptation
10. Stretch reflex
II. Fill in the blanks ( 35 points, 1 point each).
1. The regulation of physiological functions in human body includes ,______and .
2. The blood type is determined by______.
3. A subthreshold stimulus can induce a change of membrane potential which is called ______.
4. The functions of the transversal tubule and the longitudinal tubule of muscle are respectively ______and
______.
5. The three basic steps of physiological hemostasis include ______, ______and ______.
6. The autorhythmicity of cardiac muscle depends on ______, ______and ______.
7. The neural transmitter released by the postganglionic fiber of cardiac sympathetic nerve is ______, which excites the activity of the heart through acting on the ______receptor.
8. Surfactant is synthesized by and its major function is to .
9. The physiological dead space equals to the ______plus ______.
10. Digestion and absorption mainly occur in the .
11. The gastric juice secretion can be stimulated by endocrine
substances such as______、______、 and .
12. When the skin temperature is higher than environmental temperature,
the major ways of heat loss are ,
and .
13. Glomerular filtration membrane has and
barrier characteristics.
14. Nerve impulse means propagated along the nerve fiber.
15. According to the theory of “Travelling Wave”, the basilar membrane
near best with high-frequency pitches, the
basilar membrane near best with low-frequency
pitches.
16. According to the difference between the two inhibitory mechanisms,
we infer to the synaptic inhibitions as
and .
17. The pain in one of the visceral organs is referred to an area on
the body surface is called .
18. Hypothalamus communicates with anterior pituitary through
the tract named .
III. Fill in the blanks with the best choice ( 20 points, 1 piont each).
1. One of the properties of humoral regulation is being _____.
A. fast B. slow
C. accurate D. time and area limited
2. When a given stimulation reaches threshold value, a excitable cells can produce _____.
A. action potential B. contraction
C. local response D. reflex
3. The physiological significance of positive feedback is _____.
A. to keep a functional activity relatively constant
B. to keep the functional activity going on until its end
C. to maintain the blood pressure at a higher level
D. to maintain the body temperature constant
4. The main source of plasma colloid osmotic pressure is _____.
A. fibrinogen B. α globulin
C. β globulin D. albumin
5. The blood coagulation can be facilitated by _____.
A. smooth surface B. heparin
C. Ca2+ D. plasmin
6. Afterload of the left ventricle refers to _____.
A. arterial blood pressure
B. venous blood pressure
C. end-systolic pressure of the ventricle
D. end-diastolic pressure of the ventricle
7. The volume of venous return depends on the _____.
A. pressure difference between venous and atria
B. heart activity only
C. central venous pressure only
D. arterial blood pressure
8. During which phase of the ventricular action potential is the conductance to Ca2+ highest?
A. Phase 1 B. Phase 2
C. Phase 3 D. Phase 4
9. The gas exchange in the lung means the gas exchange _____.
A. between alveoli and blood of the pulmonary capillary
B. between tissue cells and capillary blood
C. among organelles
D. between lungs and tissues
10. When the P O2 in the blood decreases, the respiratory movement will be enhanced primarily due to the activation of the _____.
A. central chemoreceptor
B. peripheral chemoreceptor
C. pulmonary stretch receptor
D. stretch receptor of the respiratory muscles.
11. Which one of the following cannot increase energy metabolism rate?
A. stress
B. sleep
C. muscular activity
D. eating food
12. On which of the following does aldosterone exert its greatest effect?
A. Proximal tubule
B. Thin portion of the loop of Henle
C. Thick portion of the loop of Henle
D. Cortical collecting duct
13. Visual accommodation involves .
A. Increase of tension on the lens ligaments
B. Increase of convex of the lens
C. Increase of diameter of the pupil
D. Diverging of the eyes
14. The basilar membrane of the cochlea .
A. is unaffected by movement of fluid in the scala vestibuli
B. covers the oval window and the round window
C. vibrates in a pattern determined by the form of the traveling wave of the fluids in the cochlea
D. is under tension
15. Which one of the following can increase the secretion of renin?
A. Drinking a lot of water
B. Venous injection of 10% glucose solution
C. Stimulating the vagus nerve
D. Decrease of extracellular fluid amount
16. Administration of a drug that blocks β-adrenergic receptors would be expected to .
A. decrease the heart rate
B. decrease the force of cardiac contraction
C. decrease the secretion of renin from the kidneys
D. all are correct
17. Fast inhibitory postsynaptic potentials (IPSPs) .
A. are a consequence of presynaptic inhibition
B. interact with other fast and slow potentials to move the membrane potential of the postsynaptic neuron away from the firing level
C. can be produced by an increase in Na+ conductance
D. can be produced by an increase in Ca2+ conductance
18. Which one is the phenomenon of decerebrate animal?
A. Flexor reflex overactivated
B. Intersegmental reflex overactivated
C. Muscle tonus overactivated
D. Crossed extensor reflex overactivated
19. The type of nerve fibers responsible for conducting impulses to cause gastric receptive relaxation is .
A. adrenergic nerve fibers
B. cholinergic nerve fibers
C. amino acid nerve fibers
D. peptidergic nerve fibers
20. The final pathway of acid secretion by parietal cells is .
A. H+-K+-ATPase
B. Na+-K+-ATPase
C. HCO3--Cl- exchange
D. H+-Na+-ATPase
IV. Answer the following questions ( 20 points ).
1. What is called action potential? How is it generated in neural cells? (8points)
2. Describe the steps and significance of the baroreceptor reflex. (7 points)
3. What will happen if a person intakes 2 L of distilled water ? Why?(5 points)
Answer
I . Explain the following terms.
1. Negative feedback: The role of the feedback signal is opposite to that of the control signal or to decrease the activity of controlling system.
2. Homeostasis: It is a relatively constant state of physical and chemical properties of internal environment.
3. Resting potential: It means potential difference that exits across the membrane of a cell at rest.
4. Blood coagulation : It is the process of conversion of blood from fluid to gel .
5. Stroke volume: It is the volume ejected from the ventricle on each heat.
6. Oxygen dissociation curve: It is a plot of percent of saturation of hemoglobin as a function of PO2.
7. Digestion: It is the processes by which carbohydrates, fats and proteins are digested into absorbable molecules in the gastrointestinal tract.
8. Respiratory quotient: It is the ratio in the steady state of the volume of
CO2 produced to the volume of O2 consumed per unit of time.
9. Dark adaptation: The sensitivity of eyes to light gradually
increases so that you could begin to see the bodies in the darkened surroundings.
10. Stretch reflex: When a skeletal muscle with an intact nerve supply is stretched, it contracts. This reflex is called stretch reflex.
II. Fill in the blanks
1. nervous regulation, humoral regulation, autoregulation
2. the presence or absence of agglutinogen A or B on the RBCs membrane
3. electrotonic potential
4. Propagation of depolarization, storage and release of Ca2+
5. Formation of prothrombin activator, conversion of prothrombin to thrombin, conversion of fibrinogen to fibrin
6. velocity of automatic depolarization in phase 4, maximal repolarization potential, threshold potential
7. NE, β1
8. type Ⅱalveolar cells, reduce surface tension
9. anatomical dead space , alveolar dead space
10. small intestine
11. acetylcholine, gastrin, histamine
12. radiation, convection, evaporation
13. mechanical, electrical
14. action potential
15. oval window, helicotrema
16. presynaptic inhibition, postsynaptic inhibition
17. referred pain
18. hypophyseal portal system
III. Fill in the blanks with the best choice
1. B 2. A 3. B 4. D 5. C 6. A 7. A 8. B 9. A 10. B
11. B 12. D 13. B 14. C 15. D 16. D 17. B 18. C 19. D 20. A
IV. Answer the following questions
1. Action potential is a rapid, reversible and conductible fluctuation of
the membrane potential of excitable cell when stimulated.
1) At resting membrane potential, the Na+ channels are closed and
Na+ conductance is low.
2) Upstroke of the action potential
a. Inward current depolarizes membrane potential to threshold.
b. Depolarization causes rapid opening of the activation gates of the
Na+ channel, and the Na+ conductance of the membrane promptly increases.
c. Na+ conductance becomes higher than the K+ conductance, and the
membrane potential is driven toward the Na+ equilibrium potential. Thus,
the rapid depolarization during the upstroke is caused by an inward
Na+ current.
d. The overshoot is the brief portion at the peak of the action potential.
3) Repolarization of the action potential
a. Depolarization also causes the inactivation gates of the Na+ channel,
and the Na+ conductance returns toward zero.
b. Depolarization slowly opens K+ channels and increases K+ conductance to
even higher levels than at rest.
c. The membrane potential is repolatized. Thus, repolarization is caused by an outward K+ current.
4) Hyperpolarizing afterpotential
The K+ conductance remains higher than at rest for some time after closure
of the Na+ channels. During this period, the membrane potential is driven
very close to the K+ equilibrium potential.
2. Excitation of the baroreceptors by pressure in the arteries reflexly causes
the arterial pressure to decrease because of both a decrease in peripheral resistance and a decrease on cardiac output.
Steps in the baroreceptor reflex are as follow:
1) A increase in arterial pressure increases stretch on the walls of the carotid sinus.
2) Increased stretch increases the firing rate of the carotid sinus nerve, which carries information to the tractus solitarius of the medulla. Secondary signals inhibit the vasoconstrictor center of the medulla and excite the vagal parasympathetic center.
3) The net effects are
a. vasodilation of the veins and arterioles throughout the peripheral circulatory system.
b. decreased heart rate and strength of heart contraction.
Significance: to maintain the arterial BP at a relatively constant level in a way of negative feedback.
3. The urine volume increase. The explanation is as follow: