13.1 Physiology of Blood Circulation

Question 1

where is the cardiovascular center located

Answer 1

medulla oblongata

Question 2

how is output sent from the cardiovascular center

Answer 2

via sympathetic and parasympathetic neurons

Question 3

what are the functions of the sympathetic cardiac acclamatory nerves (2)

Answer 3

release the norepiniephrine increasing the rate of and force of the hearts contractions
cause vasoconstriction and an increase in blood pressure

Question 4

what are the functions of the parasympathetic cardiac inhibitory nerves

Answer 4

release acetylcholine which decreases heart rate and has a lesser effect on decreasing the force of contraction

Question 5

what is a function of the cardiovascular center

Answer 5

continuously sends impulses to the smooth muscle in blood vessel walls

Question 6

What sets the rhythm of the hearts contractions?

Answer 6

specialized cardia cells called auto-rhythmic fibers, pacemaker cells

Question 7

What does norepinephrine do to blood vessels

Answer 7

increase heart rate therefore constrict veins and arterioles

Question 8

what does epinephrine do to blood vessels

Answer 8

dialate arterioles to increase blood flow

Question 9

what is electrocardiography

Answer 9

the measurement and analysis of currents associated with heart activity

Question 10

what is electrocardiography important for

Answer 10

the diagnosis of abnormal cardiac function

Question 11

what is an ECG/EKG

Answer 11

the recording of the electrical changes of the heart

Question 12

what does a normal electrocardiogram consist of

Answer 12

p wave
qrs complex
t wave

Question 13

what does the p wave of an electrocardiogram indicate

Answer 13

atrial depolarization

Question 14

what does the qrs complex of an electrocardiogram indicate

Answer 14

ventricular depolarization

Question 15

what does the t wave of an electrocardiogram indicate

Answer 15

ventricular repolarization

Question 16

what happened when acetylcholine was applied to a frog heart

Answer 16

it decreased the force of contraction

waves of the electrocardiogram got smaller and wider

Question 17

what happened when epinephrine was applied to a frog heart

Answer 17

it increased the force of contraction

waves of the electrocardiogram gat taller and narrower

Question 18

is epinephrine released by the sympathetic or parasympathetic system?

Answer 18

sympathetic

Question 19

acetylcholine released by the sympathetic or parasympathetic system

Answer 19

parasympathetic

Question 20

what does the term pulse refer to

Answer 20

alternating surges of pressure in an artery that can occur with each contraction and relaxation of the left ventricle

Question 21

what is the normal resting pulse

Answer 21

70-76 beats per min

Question 22

in clinical terms what does blood pressure refer to

Answer 22

arterial blood pressure

Question 23

when heart muscle is in a contracted state what is it called

Answer 23

systole

Question 24

when the heart muscle is in a relaxed state what is it called

Answer 24

diastole

Question 25

how is systolic pressure defined

Answer 25

maximum pressure in the arteries during ventricular contraction

Question 26

how is diastolic pressure defined

Answer 26

minimum pressure in the arteries during ventricular relaxation

Question 27

why does blood pressure change when someone is reclining

what role do baroreceptors play

Answer 27

heart and rest of the body are on the same plane, therefor easier to pump blood throughout the body since blood flow is not against gravity (blood pressure decreases)
baroreceptors sense the blood pressure changes

Question 28

would blood pressure and pulse rate increase when standing for long periods?

Answer 28

yep receptors would signal the need to increase blood pressure in order to get pulse to a normal rate

Question 29

explain the changes in blood pressure and pulse rate immediately after exercise and once exercise has ceased

Answer 29

heart pumps harder in order to increase oxygen supply to muscles during exercise
blood pressure/pulse will return to normal within 5mins of resting

Question 30

how would you expect trained athletes and an unfit person differ in effects of exersice

Answer 30

unfit person would have increased blood pressure compared to the athlete

Question 31

what would be the effect of drinking a cup of highly caffeinated beverage on pulse rate

Answer 31

it would increase heart rate as caffeine is a stimulant

Question 32

what is hypertension

Answer 32

sustained increase in systolic or diastolic blood pressure

Question 33

why is prolonged hypertension dangerous?

Answer 33

can damage you blood vessels resulting in ruptures, strokes, leaks

Question 34

what is arterioclerosis what does it lead to

Answer 34

hypertension - blood has to pump harder with the pressure increase; systolic arteries gave decreased lumen size, loose elasticisty

Question 35

why are veins readily affected by external factors? What are some external factors

Answer 35

because of the thinness of the walls

muscle activity, gravity, and pressure changes in the thorax such as breathing

Question 36

how do veins preven blood flow backwards

Answer 36

they have valves