Cardiovascular 8

Question 1

Baroreceptor reflex

Answer 1

Primary reflex pathway for homeostatic control of MAP
-maintains MAP

Question 2

Barcoreceptors are

Answer 2

Tonically active stretch sentisitive mechanoreceptors
-situated on aorta and on carotid artery
-sense changes in pressure of arteries

Question 3

Increase in BP causes baroreceptors to

Answer 3

Sense the stretch in artery walls, increase their firing rate

Question 4

Decrease in BP causes baroreceptors to

Answer 4

Sense stretch, decrease their firing rate

Question 5

Baroreceptor reflex happens

Answer 5

Very quickly, within a few heartbeats

Question 6

Orthostatic hypotension

Answer 6

Standing up quickly, dizzy and foggy
-cardiac output falls from 5L/min to 3L/min

Question 7

Peripheral Chemoreceptors

Answer 7

-located on the aortic arch and carotid artery
-sense alterations in blood - gas concentrations, and changes in blood pH
-for proper ventilation and blood flow through system
-send into back to CVCC, changes autonomic output for gas levels

Question 8

Vasovagal Syncope

Answer 8

Hypothalamus capable of altering CV function in response to emotional stress
-fainting from emotion, sight of blood, needles, etc

Question 9

Vasovagal Syncope results in

Answer 9

A large increase in parasympathetic output (decrease Q) and reduction in sympathetic output (large decrease in peripheral resistance because of fall in BP)
-these cause a large fall in MAP

Question 10

Bulk Flow

Answer 10

Mass movement of fluid as the result of hydrostatic or osmotic pressure gradients
-in and out of interstitial fluid

Question 11

Absorption

Answer 11

Bulk flow is resulting in fluid moving into the capillaries from interstitial fluid

Question 12

Filtration

Answer 12

If bull flow is resulting in the movement of fluid out of the capillaries out into the interstitial fluid

Question 13

Hydrostatic Pressure

Answer 13

The pressure in the blood vessels drives fluid out of capillaries through pores and cell junctions

Question 14

Colloid Osmotic Pressure/ Oncotic Pressure

Answer 14

Pressure that draws fluid into the capillaries is the pressure created by plasma proteins in the blood
-osmotic pressure created by proteins

Question 15

Lymphatic vessels:

Answer 15

Assist the CV system with returning fluid and proteins lost through capillaries
-similiar to capillaries with a single endothelial layer

Question 16

Lymphatic Vessels contain large

Answer 16

Interendothelial junctions that act like one way valves
-allows fluid, bacteria, etc to be pulled in to autoimmune cells

Question 17

Pressure Gradient in Lymphatic Vessels

Answer 17

Initial: Higher than inside the lymphatic -causing microvalves to open and fluid goes in
-as it fills, pressure exceeds interstitial, so secondary valves open and flow into interstitial

Question 18

Collecting Lymphatics Contain what

Answer 18

Smooth muscle
-actively contracts to propel fluid and one way valves to prevent backflow, with assist from skeletal muscle

Question 19

What is Edema?

Answer 19

An abnormal accumulation of fluid in the interstitial space
-swelling!

Question 20

Edema arises for what 2 reasons?

Answer 20

1. Inadequate lymph drainage : blockage in the lymphatic system
2. Disruption in normal balance between capillary filtration and absorption, where filtration is greater than absorption
   -heart failure, malnutrition/ liver failure,, excessive leakage of proteins (injury)

Question 21

Velocity of blood flow =

Answer 21

Flow rate/ cross sectional area

Question 22

The rate at which blood flows through the capillaries plays a role in

Answer 22

The efficiency of exchange between the blood and interstitial fluid

Question 23

Single capillaries have a very small CSA, but

Answer 23

All the capillaries together have a VERY large CSA

Question 24

Slow blood velocity ensures

Answer 24

Adequate gas and nutrient exchange at the capillaries

Question 25

Discorders of the heart and blood vessels lay a role in

Answer 25

1/3 deaths in the US
-things like heart attacks and strokes
-40% of US will have SV disease by 2030

Question 26

Uncontrolled Risk factors of CV Disease

Answer 26

Age, sex, genetics

Question 27

Controlled risk factors of CV Disease

Answer 27

Smoking, obesity, sedentary lifestyle, untreated hypertension