packet 6

Question 1

Overall function of cardiovascular system and blood flow in general is affected by

Answer 1

Blood Pressure
Resistance
Venous Return
Velocity and Volume

Question 2

force exerted by circulating blood on the walls of blood vessels

Answer 2

blood pressure

Question 3

systolic - diastolic

important measure of stress exerted on small arteries

Answer 3

pulse pressure

Question 4

Factors that determine systemic vascular resistance

Answer 4

Blood viscosity
Vessel length
Radius
Laminar flow

Question 5

7-13 mm Hg venous pressure towards heart

Answer 5

Pressure gradient

Question 6

inhalation - thoracic cavity expands (pressure ) abdominal pressure , forcing blood upward
central venous pressure fluctuates

Answer 6

thoracic pump

Question 7

Exercise increase venous return in many ways

Answer 7

heart beats faster, harder - increase cardiac output (CO) and BP
vessels of skeletal muscles, lungs and heart dilate increase flow
increase respiratory rate increase action of thoracic pump
increase skeletal muscle pump

Question 8

venous pressure not enough force blood upward

with prolonged standing, CO may be low enough to cause dizziness or syncope the following cause

Answer 8

venous pooling

Question 9

Vasoconstriction of blood vessel smooth muscle is controlled both by

Answer 9

the autonomic nervous system and at the local level (sympathetic increase parasympathetic decrease)

Question 10

Four factors control arterial flow at the organ level (includes body position):

Answer 10

change in metabolic activity

• changes in blood flow
• stretch of arterial smooth muscle
• local chemical messengers

Question 11

Blood pressure is a key factor for providing blood (oxygen and energy)

Answer 11

to organs

Question 12

Systolic pressure must be at least 70 to sustain

Answer 12

kidney

filtration and adequate blood flow to the brain

Question 13

Role of Cardiovascular center

Answer 13

Collection of nuclei that affect rate, force, vessel diameter

Question 14

Signals sent out through vagus (parasympathetic)

Answer 14

lowers heart rate

Question 15

help regulate heart rate & stroke volume

specific neurons regulate blood vessel diameter - sympathetic vasomotor nerves

Answer 15

nuclei

Question 16

carotid and aortic sinuses sense the blood pressure in the aortic arch and internal carotid  send signal to the vasomotor center in the medulla oblongata
Other information are sent from the hypothalamus, cortex

Answer 16

Baroreceptors

Question 17

Effects help maintain the blood flow to the brain at arterial pressure too low to activate the baroreceptors.

activated by hypoxia, hypocapnia, and acidosis are located in the aortic arch and carotid sinus.
Stimulated during asphyxia and severe hypotension.
Changes breathing, and include sympathetic constriction of (mainly skeletal muscle) arterioles and tachycardia resulting indirectly from the increased lung inflation.

Answer 17

chemoreceptors

Question 18

Monitor blood pressure and take corrective action if it should drop.
Leads to a cascade of events eventually producing angiotensin II

Answer 18

kidney

Question 19

constricts the walls of arterioles closing down capillary beds;
stimulates the proximal tubules in the kidney to reabsorb sodium ions;
stimulates the adrenal cortex to release aldosterone. Aldosterone causes the kidneys to reclaim still more sodium and thus water
stimulates the pituitary to release the ADH

Answer 19

Angiotensin II

Question 20

A rise in blood pressure stretches the atria of the heart, triggers release of atrial natriuretic peptide (ANP).
ANP lowers blood pressure
The effects on the kidney reduce the reabsorption of water = increase flow of urine - the net effect = reduce blood pressure by reducing the volume of blood in the system.

Answer 20

heart

Question 21

increases heart rate & force of contraction
causes vasoconstriction in skin & abdominal organs
vasodilation in cardiac & skeletal muscle

Answer 21

Epinephrine & norepinephrine

Question 22

is ability to make these changes as needed by demand for O2 & waste removal

Answer 22

autoregulation

Question 23

released from cells alter vessel diameter
(K+, H+, lactic acid, NO)
systemic vessels dilate in response to low levels of O2
pulmonary vessels constrict in response to low levels of O2

Answer 23

vasoactive substance

Question 24

cause changes in each capillary bed
autoregulation is ability to make these changes as needed by demand for O2 & waste removal
important for tissues that have major increases in activity (brain, cardiac & skeletal muscle)

Answer 24

local factors

Question 25

Constriction of arterioles leading to resistance in blood flow and strain on the heart
chronic resting BP > 140/90

Answer 25

hypertension

Question 26

chronic low resting BP

caused by blood loss, dehydration, anemia

Answer 26

hypotension

Question 27

Any state where cardiac output insufficient to meet metabolic needs (inadequate cardiac output = not enough O2 to meet metabolic needs)

Answer 27

shock and homeostasis

Question 28

inadequate pumping of heart

Answer 28

cardiogenic shock

Question 29

low venous return (LVR) shock - 3 principle forms

Answer 29

1. hypovolemic shock
2. obstructed shock
3. venous pooling

Question 30

most common

loss of blood volume: trauma, burns, dehydration

Answer 30

hypovolemic shock

Question 31

tumor or aneurysm

Answer 31

obstructed venous return shock

Question 32

long periods of standing, sitting or widespread vasodilation

Answer 32

venous pooling

Question 33

loss of vasomotor tone, vasodilation, causes from emotional shock to brainstem injury

Answer 33

neurogenic shock

Question 34

bacterial toxins trigger vasodilation and increase capillary permeability

Answer 34

septic shock

Question 35

severe immune reaction to antigen, histamine release, generalized vasodilation, increase capillary permeability

Answer 35

anaphylactic shock

Question 36

An extremely low blood pressure
Fast but weak pulse
Dizziness, faintness or 
      light-headedness
Moist, clammy skin
Profuse sweating
Unconsciousness
Rapid, shallow breathing 
Chest pain
Blue lips and fingernails

Answer 36

signs and symptoms of shock