Muscle
Which of the following statements is NOT characteristic of smooth muscles?
a. Myosin phosphatase is required for contraction
b. They can conduct graded depolarizations
c. They can enter a latch state
d. They can produce graded contractions in response to graded depolarizations
a. Myosin phosphatase is required for contraction
Platelets:
a. form a plug by sticking to each other
b. release chemicals that stimulate vasoconstriction
c. provide phospholipids needed for the intrinsic pathway
d. serve all of these functions
d. serve all of these functions
Which of these statements about tissue fluid is false?
a. it contains the same glucose and salt concentration as plasma
b. it contains a lower protein concentration than plasma
c. its colloid osmotic pressure is greater than that of plasma
d. its hydrostatic pressure is lower than that of plasma
c. its colloid osmotic pressure is greater than that of plasma
The maximum amount of air that can be expired after a maximum inspiration is:
a. tidal volume
b. forced expiratory volume
c. vital capacity
d. maximum expiratory flow rate
c. vital capacity
Which of these statements about the partial pressure of carbon dioxide is true?
a. it is higher in the alveoli than in the pulmonary arteries
b. it is higher in the systemic arteries than in the tissues
c. it is higher in the systemic veins than in the systemic arteries
d. it is higher in the pulmonary veins than in the pulmonary arteries
c. it is higher in the systemic veins than in the systemic arteries
What is an example of an eccentric muscle contraction?
a. doing a "curl" with a dumbbell
b. doing a breast stroke in a swimming pool
c. extending the arms when bench-pressing a weight
d. flexing the arms when bench-pressing to allow the weight to return to the chest
d. flexing the arms when bench-pressing to allow the weight to return to the chest
Production of which of the following blood cells is stimulated by a hormone secreted from the kidneys?
a. lymphocytes
b. monocytes
c. erythrocytes
d. neutrophils
e. thrombocytes
c. erythrocytes
Bonus: What is the hormone called?
In the absence of compensations, the stroke volume will decrease when:
a. blood volume increases
b. venous return increases
c. contractility increases
d. arterial blood pressure increases
d. arterial blood pressure increases
If the blood lacked red blood cells but the lungs were functioning normally...
a. the arterial PO2 would be normal
b. the oxygen content of arterial blood would be normal
c. both a and b would apply
d. neither a nor b would apply
a. the arterial PO2 would be normal
All of the following can bind with hemoglobin EXCEPT:
a. HCO3-
b. O2
c. H+
d. CO2
e. NO
a. HCO3-
When a muscle shortens during contraction, which of these statements is false?
a. the A bands shorten
b. the H bands shorten
c. the I bands shorten
d. the sarcomeres shorten
a. the A bands shorten
During the phase of isovolumetric relaxation of the ventricles, the pressure in the ventricles is:
a. rising
b. falling
c. first rising, then falling
d. constant
b. falling
Both ADH and aldosterone act to:
a. increase urine volume
b. increase blood volume
c. increase total peripheral resistance
d. produce all of these effects
b. increase blood volume
The affinity of hemoglobin for oxygen is decreased under conditions of:
a. acidosis
b. fever
c. anemia
d. acclimatization to high altitude
e. all of these
e. all of these
The second heart sound immediately follows the occurrence of:
a. P wave
b. QRS wave
c. T wave
c. T wave
Electrical excitation of a muscle fiber most directly causes:
a. movement of tropomyosin
b. attachment of cross bridges to actin
c. release of Ca2+ from sarcoplasmic reticulum
d. splitting of ATP
c. release of Ca2+ from sarcoplasmic reticulum
The "lub" (first heart sound) is produced by closing of:
a. aortic semilunar valve
b. pulmonary semilunar valve
c. tricuspid valve
d. bicuspid valve
e. both AV valves
e. both AV valves
Bonus: Is this produced at the beginning of systole, end of systole, beginning of diastole, or the end of diastole?
Blood flow in the coronary circulation:
a. increases during systole
b. increases during diastole
c. remains constant throughout the cardiac cycle
b. increases during diastole
Most of the carbon dioxide in the blood is carried in the form of:
a. dissolved CO2
b. carbaminohemoglobin
c. bicarbonate
d. carboxyhemoglobin
c. bicarbonate
The chemoreceptors in the medulla are directly stimulated by:
a. CO2 from the blood
b. H+ from the blood
c. H+ in brain interstitial fluid derived from blood CO2
d. decreased arterial PO2
c. H+ in brain interstitial fluid derived from blood CO2
Which of these muscle types are not capable of spontaneous depolarization?
a. single-unit smooth muscle
b. multiunit smooth muscle
c. cardiac muscle
d. skeletal muscle
e. both B and D
f. both A and C
e. both B and D
The cells that normally have the fastest rate of spontaneous diastolic depolarization are located in:
a. SA node
b. AV node
c. bundle of His
d. Purkinje fibers
a. SA node
An increase in blood volume will cause:
a. a decrease in ADH secretion
b. an increase in Na+ excretion in the urine
c. a decrease in renin secretion
d. all of these
d. all of these
Bonus: Blood pressure is lowest in the arteries, arterioles, capillaries, venules, or veins?
Which of these occur(s) during hypoxemia?
a. increased ventilation
b. increased production of 2,3-DPG
c. increased production of erythropoietin
d. all of these
d. all of these
Angiotensin II:
a. stimulates vasoconstriction
b. stimulates the adrenal cortex to secrete aldosterone
c. inhibits the action of bradykinin
d. does all of these
d. does all of these