Human Phys 5.1

Question 1

What is the role of the autonomic nervous system?

Answer 1

Redistribution of blood flow

Increasing pumping activity of the heart

Rapid control of arterial pressure

Question 2

What is the sympathetic nervous system important in the control of?

Answer 2

Circulation(cardiac function)

Question 3

What is the parasympathetic nervous system important for?

Answer 3

Regulating heart function

Question 4

What do the sympathetic nerve fibers innervate?

Answer 4

All vessels except capillaries, precapillary sphincters, and some metarterioles

Question 5

What do innervation of small arteries and arterioles allow?

Answer 5

Sympathetic nerves to increase vascular resistance

Question 6

How are large veins and the heart innervated?

Answer 6

Sympathetically

Question 7

How does the parasympathetic control the heart rate?

Answer 7

Vagus nerve

Question 8

Where does the vasomotor center transmit impulses?

Answer 8

Downward through the cord to almost all blood vessels

Question 9

Where is the vasomotor center located?

Answer 9

Bilaterally in the reticular substance of the medulla and the lower third of the pons

Question 10

What is the vasomotor center composed of?

Answer 10

Vasoconstrictor area (SNS)

Cardiac accelerator center (SNS)

Cardiac decelerator center (PNS)

Question 11

What is the effect of sympathetic outflow?

Answer 11

Effect on SA node (increase HR)

Effect on cardiac muscle (increase contractility and SV)

Effect on arterioles (vasoconstriction and increased TPR)

Effect on veins (venoconstriction and increased venous return)

Question 12

What is the effect of parasympathetic outflow?

Answer 12

Effect on SA node via vagus nerve (decreased HR)

Question 13

Where does the vasomotor area of the vasomotor center transmit signals continuously?

Answer 13

To a sympathetic nerve fiber called sympathetic vasoconstrictor tone

Question 14

What do signals sent to the sympathetic vasoconstrictor tone do?

Answer 14

Maintain partial state of contraction in blood vessels called vasomotor tone

Question 15

What does the cardiac accelerator center of vasomotor center do?

Answer 15

Controls heart activity by increasing HR and contractility

Question 16

What does the cardiac decelerator center of the vasomotor center do?

Answer 16

Transmit signals via vagus nerve to decrease HR

Question 17

What is the neurotransmitter for the vasoconstrictor nerves?

Answer 17

Norepinephrine

Question 18

What does the adrenal medulla secrete?

Answer 18

Epinephrine and norepinephrine

Question 19

What does the secretion of epinephrine and norepinephrine from the adrenal medulla do?

Answer 19

Constricts blood vessels via alpha adrenergic receptors

Question 20

What can epinephrine do?

Answer 20

Dilate vessels through beta receptors

Question 21

How can the nervous system via the vasomotor center increase arterial pressure?

Answer 21

Constricting almost all arterioles of the body which increases TPR

Constricting large vessels of the circulation thereby increasing venous return and CO

Directly increases CO by increasing HR and contractility

Question 22

How can rapid increases in arterial pressure occur?

Answer 22

During exercise or with fright