Cardio Lecture 2--Structure And Function Of The Cv System

Front 1

Who was the first to describe the cardiovascular system?

Back 1

Galen

Front 2

Who proved that circulation was an intact system?

Back 2

William Harvey

Front 3

No cell is more than how far from a capillary?

Back 3

10 microns

Front 4

What are the three layers of the pericardium?

Back 4

The fibrous layer, pericardial cavity, and visceral layer

Front 5

Cardiac tamponade does what?

Back 5

Increases the amount of fluid in the pericardial cavity

Front 6

True/False: The cardiac conduction system is just modified cardiac muscle

Back 6

TRUE

Front 7

What is the order of stimulation of the heart?

Back 7

SA node --> AV node in the septum between ventricles --> Bundle branches --> Purkinje fibers

Front 8

True/False: The force of pumping action of the heart drives blood through the system

Back 8

FALSE--it is the pressure drop from the left side of the heart across circulation to the right side of the heart

Front 9

Why does the right chamber of the heart have less muscle?

Back 9

Because it pumps blood at a lower pressure in the pulmonary circuit

Front 10

What happens when the papillary muscles are contracted?

Back 10

The chordae tendinae become taut and the valves close

Front 11

What valves can regurgitation occur in and what happens?

Back 11

The mitral and aortic valves can allow regurgitation and this allows blood to leak from system back into the heart chambers and therefore you will have less cardiac output to deliver

Front 12

What is stenosis and what valves can it occur in? What happens as a result?

Back 12

Mitral and aortic valves undergo hardening due hardening due to scar tissue formation and in order to deliver the same cardiac output, the intercardiac pressure has to increase and cardiac hypertrophy results

Front 13

What forms the majority of the cardiac extracellular matrix?

Back 13

COLLAGEN--hold capillaries close to myocytes for nourishment

Front 14

If too much collagen is produced in the heart...?

Back 14

It becomes rigid and less able to contract

Front 15

What is angina pectoris?

Back 15

It is the compromise or partial block of coronary vessels attributed to plaque buildup

Front 16

When does collateral circulation occur?

Back 16

When there is a coronary block--vessels emerge from the healthy parts of the artery

Front 17

What makes up the collecting system?

Back 17

vena cavae and systemic veins

Front 18

True/False: All vessels except venules contain endothelium.

Back 18

FALSE--they all have it

Front 19

How does cardiovascular endothelium relate to the vascular smooth muscle in vessels? What are 3 interaction types?

Back 19

Endothelium forms a functional unit with the VSM cells and produces substances to maintain vascular tone. 1. Mechanical--VSM contraction compresses the endothelium 2. Electrical--agonists act on the endothelium and induce a membrane potential change coupled via gap junctions 3. Chemical--NO

Front 20

What is stimulated by shearing forces?

Back 20

NO

Front 21

How does NO work directly and how does it work indirectly?

Back 21

It causes vasodilation directly by diffusing into VSM cells and indirectly by inhibiting vasoconstrictor influences = angiotensin II and the symp. nervous system

Front 22

True/False: NO inhibits platelet adhesion to the endothelium

Back 22

TRUE

Front 23

The break down of endothelium is what?

Back 23

The MAJOR CAUSE OF ATHROSCLEROSIS AND HYPERTENSION

Front 24

How are arteries able to contract?

Back 24

Sympathetic neuron stimulation causes contraction--norepi = vasoconstriction; block norepi = vasodilation

Front 25

What allows for continuous flow in the body?

Back 25

The elastic tissue in arteries--distensible and responsive

Front 26

What provides most of the resistance to blood flow in the circuit? What can they do?

Back 26

ARTERIOLES--control the fractional distribution of blood flow to various capillary beds