Ch 20. The Heart

Question 1

What is an artery?

Answer 1

carries oxygenated blood away from the heart

Question 2

What is a Vein?

Answer 2

a blood vessel that carries deoxygenated blood toward the heart

Question 3

Capillaries

Answer 3

blood vessels that connect arteries to veins. Smallest vessels where exchange of gases, nutrients, waste products occur.

Question 4

Where is the Heart Located?

Answer 4

In the mediastinum, left midline, behind sternum

Question 5

Shape of the Heart

Answer 5

Is determined by the shape of the thoracic cavity

Question 6

What is the pericardium?

Answer 6

surrounds the heart with a double layer serous membrane

Question 7

Visceral pericardium

Answer 7

Stuck to the surface of the heart

Question 8

Parietal Pericardium + Visceral Pericardium make…

Answer 8

Serous Pericardium

Question 9

Coronary Sulcus

Answer 9

between right and left ventricle

Question 10

What is the job of ventricles?

Answer 10

To pump blood

Question 11

What is the job of ventricles?

Answer 11

To pump blood

Question 12

The pulmonary trunk branches out to where?

Answer 12

To the left and right pulmonary arteries

Question 13

What are the three layers of the heart? Describe their function.

Answer 13

Endocardium (inner most layer): Epithelial lining that lines the heart and forms the valves of heart; continuous w/ endothelial to line blood vessels

Myocardium (thickest layer): made of cardiac muscle; connected with intercalated discs

Epicardium (outer most layer): on the heart;

Question 14

Explain the order of blood flow in the heart.

Answer 14

SVC/ IVC > RA > Tricuspid Valve > RV > Pulmonary V > Pulmonary Trunk > R & L Pulmonary arteries > Lungs > R & L Pulmonary Veins > LA > Bicuspid Valve > LV > Aorta

Question 15

Cardiac Muscle is a

Answer 15

function syncytium ( to allow cardiac muscles to contract at the same time)

Question 16

What are intercalated discs?

Answer 16

They connect myocardial cells

Question 17

What happens during action potential in cardiac muscles?

Answer 17

SA Node > Inter-nodal Bundle > Bundle of His

Question 18

What is the visceral layer and parietal layer?

Answer 18

Visceral pericardium wraps around the heart and parietal pericardium is the lining of the fibrous pericardium.

Question 19

Functions of connective tissue are….

Answer 19

Stores fat, transports substances, binds structures together, form a framework and support for organs and body, protects against disease, help repair tissue damage

Question 20

Where is the heart located?

Answer 20

In the mediastinum toward left midline

Question 21

How is pericardial fluid formed and what is it’s importance?

Answer 21

Visceral pericardium and parietal pericardium secrete pericardial fluid in the pericardial space to lubricate the expansion and contraction of the heart.

Question 22

Auto-rhythmic means…

Answer 22

It does not need to be innervated to contract

Question 23

What determines when valve opens/closes?

Answer 23

The pressure of blood flow

Question 24

What separates the Left and Right Ventricle?

Answer 24

Interventricular septum

Question 25

What is the purpose of having valves in the heart?

Answer 25

To guarantee the direction of blood flow in the heart

Question 26

How does the chordae tendineae help the valves?

Answer 26

They are string-like chords that keep the valve from opening backwards and pull against the pressure in the blood.

Question 27

What are papillary muscles?

Answer 27

Pulls on cordae tendineae for it to pull against pressure of blood

Question 28

What is trabeculae carneae?

Answer 28

Pulls the wall of the ventricle during a contraction

Question 29

Electrical signal is carried…

Answer 29

From the interventricular septum to right ventricular free wall

Question 30

Why is the left free wall thicker than the right free wall?

Answer 30

More muscle is needed to move blood at a greater distance. Right pumps blood to lungs and Left pumps to rest of body.

The left ventricle also has to work against higher pressure.