Lecture #7 Cardiovascular System: Control of Blood Pressure & Flow

Question 1

What are the neurons of the cardiovascular center?

Answer 1

Sympathetic neurons, parasympathetic neurons, and vasomotor neurons.

Question 2

Which neuron increases Heart rate and contractility?

Answer 2

Sympathetic Neurons

Question 3

What neuron decreases heart rate?

Answer 3

Parasympathetic Neurons

Question 4

Which neuron regulates vessel diameter and is also known as a sympathetic nerve that synapse on arteriolar smooth muscle and cause vasoconstriction?

Answer 4

Vasomotor Neurons

Question 5

What does the cortex, limbic system, and the hypothalamus do in the cardiovascular system?

Answer 5

CV neurons receive input from higher brain centers

Question 6

Where does the CV neurons receive input from peripheral afferent nerve fibers?

Answer 6

Barorecptors, chemoreceptors, and proprioceptors.

Question 7

What are the output effectors that increase the frequency of nerve impulses?

Answer 7

Cardiac inhibitor, Cardiac accelerator, and vasomotor nerves–CV center.

Question 8

What happens to the heart if the heart rate decreases?

Answer 8

Due to Cardiac Inhibitor

Question 9

What happens to the heart rate increase and contractility?

Answer 9

Due to Cardiac Accelerator

Question 10

What happened to the blood vessels when they are vasoconstriction?

Answer 10

Due to vasomotor nerves

Question 11

What are the cardiovascular reflexes?

Answer 11

They are produced by afferent signaling of baroreceptors, chemoreceptors, proprioceptors.

Question 12

Which reflexes are more important in the CV regulation?

Answer 12

Baroreceptors and chemoreceptors

Question 13

Where is the Baroreceptors located?

Answer 13

High pressure baroreceptors are located in the carotid sinus and aortic arch.

Question 14

What cranial nerves help with input of baroreceptors into the CV center?

Answer 14

Cranial nerve IX and Cranial nerve X (Glossopharyngeal & Vagus)

Question 15

Where are low pressure baroreceptors located?

Answer 15

In the walls of the right atrium and vena cavae.

Question 16

What cranial nerve is carried to the CV center with input from low pressure baroreceptors?

Answer 16

Cranial nerve X (Vagus)

Question 17

Where are chemoreceptors located?

Answer 17

Located in the carotid sinus and in the walls of the ascending arota.

Question 18

Where is carotid sinus receptors located at?

Answer 18

Reach the medulla via cranial nerve IX

Question 19

Where is aortic receptors located at?

Answer 19

Reach the medulla via cranial nerve X

Question 20

What ions does Chemoreceptors respond to?

Answer 20

Respond to increased hydrogen ion content, increased CO2, and reduced O2 (hypoxia)

Question 21

Does chemoreceptors activate SNS or PNS and what does it lead to?

Answer 21

They activate the SNS which leads to an increase in heart rate, stroke volume, and vasoconstriction.

Question 22

What is Catecholamines?

Answer 22

(NE and EPI) circulate, and bind directly to cardiac muscle fibers and to blood vessel smooth muscle cells (hormonal control of blood pressure)

Question 23

What effect does catcholamines cause?

Answer 23

Increases in heart rate, stroke volume, and constrictions of veins and arterioles.

Question 24

Arteries supplying the brain and heart have more smooth muscles and are subject to vasoconstriction by the SNS or catcholamines.

True or False

Answer 24

False……arteries supplying the brain and heart have little smooth muscle and are not subject to vasoconstriction by the SNS or catecholamines.

Question 25

Are the arteries (vessels) regulated?

Answer 25

These vessels are autoregulated.

Question 26

What other chemicals that increase blood pressure?

Answer 26

Antidiuretic hormone (ADH), Angiotensin II, and Aldosterone.

Question 27

What hormone causes widespread vasoconstriction in cases of extremely low Blood Pressure?

Answer 27

Antidiuretic Hormone (ADH)

Question 28

What hormone causes intense vasoconstriction when renal perfusion is inadequate?

Answer 28

Angiotensin II

Question 29

What hormone causes water retention and increases blood volume?

Answer 29

Aldosterone

Question 30

Which hormone is most powerful in vasoconstrictor and it usually acts on all arterioles simultaneously when released into the blood?

Answer 30

Angiotensin II

Question 31

Is it high blood pressure or low blood pressure that results in the release of renin by the kidney?

Answer 31

Low blood pressure

Question 32

Angiotensinogen converts ____into angiotensin I, and the lungs convert AT I into _______by angiotensin converting enzyme (ACE) which is located in the ________cells of the lung

Answer 32

Renin, AT II, Endothelial

Question 33

What is aldosterone?

Answer 33

Angiotensin regulates Aldersterone secretion—–Elevated AT II levels —-> aldosterone secretion by the adrenal cortex

Question 34

What happens in aldosterone?

Answer 34

Increases salt and water reabsorption and raises blood pressure by raising blood volume

Question 35

What chemicals decrease blood pressure?

Answer 35

Atrial natriuretic peptide, and Histamine.

Question 36

Released by cells of the atria when blood pressure is high is called?

Answer 36

Atrial natriuretic peptide

Question 37

What does ANP cause?

Answer 37

Causes vasodilation and promotes loss of water and salt by the kidneys—reducing blood volume & vasoconstriction

Question 38

Released by mast cells causes vasodilation by relaxing blood vessel smooth muscle is called what?

Answer 38

Histamine

Question 39

What is histamine role play?

Answer 39

Increasing blood flow to inflamed or damaged tissue.

Question 40

The level of tissue metabolic activity is called?

Answer 40

Major regulator factor

Question 41

Metabolic or “_______” is blood vessel dilation due to substances that are released by ______

Answer 41

“local” regulation, tissue cells

Question 42

_____of flow refers to changes in flow due to vasoconstriction

Answer 42

Neural regulation

Question 43

_____of flow refers to changes in vessel diameter due to circulation hormones.

Answer 43

Humoral control