Cardiovascular Physiology

1.   If an infant developed a fever of 40 degrees C (104 degrees F), its heart rate would probably
a.   stay the same as when there was no fever.
b.   decrease.             
c.   increase.
d.   stop completely.

2.   Explain the effect that decreasing the temperature had on the frog heart.  How do you think the human heart would respond?

3.   Describe why Ringer’s solution is required to maintain heart contractions.

4.   Explain the effect that increasing the temperature had on the frog heart rate.  How do you think the human heart would respond?

36.   Describe how medicines called “calcium channel blockers” are used to treat patients and why?

34.   True or False:  Calcium ions had the most pronounced effect on heart rate compared to potassium or sodium.

31.   As discussed in your lab manual, any ion or chemical that affects the heart rate is called ________; an ion or chemical that affects the force of contraction is called _______.

32.   The resting cardiac muscle cell favors the movement of which ion more than others?
a.   potassium
b.   sodium      
c.   calcium
d.   magnesium

1.   Describe the benefits of administering digitalis.

2.   Distinguish between cholinergic and adrenergic chemical modifiers.  Include examples of each in your discussion.

26.   True or False:  A ?-1 receptor can bind both epinephrine and norepinephrine. 

1.   Chemical modifiers that inhibit, mimic, or enhance the action of the neurotransmitter acetylcholine in the body are labeled _________________________.

2.   If the modifier works in the same fashion as the neurotransmitter, it is an ____________.   If it works I opposition to the neurotransmitter, it is an _______________.

16.   What do you think would happen to the heart rate if the vagus nerve were surgically cut?

10.   True or False:  Both the sympathetic nervous system and the parasympathetic nervous system can cause the heart rate to change and affect the strength of contraction of the heart. 

12.   Both the vagus nerve and a branch of the sympathetic nervous system innervate the
a.   heart muscle.
b.   sinoatrial (SA) node.
c.   bundle of His.
d.   Purkinje fibers.