Chapter 13 Cardiovascular System

Question 1

Distinguish between the visceral pericardium and the parietal pericardium

Answer 1

The visceral pericardium covers the heart and then turns back on itself for an outer covering called the pericardium

Question 2

Describe the layers of the heart wall

Answer 2

The epicardium protects the heart by reducing friction
The myocardium consists mostly of cardiac muscle tissue
The endocardium contains epithelium and connective tissue.

Question 3

Name and locate the four chambers of the heart

Answer 3

Right atrium is above the right ventricle the left atrium is above the left ventricle separated by interventricular septum

Question 4

Describe the function of each heart valve

Answer 4

The tricuspid valve allows blood to move from the right atrium to the right ventricle.
The pulmonary valve allows blood to leave the right ventricle
The mitral valve allows blood to pass from the left atrium to the left ventricle
The aortic valve allows blood to leave the left ventricle

Question 5

Review the path of blood through the heart

Answer 5

Blood enters the right atrium through the vena cava and coronary sinus then passes through the tricuspid valve and enters the right ventricle then it’s pushes through the pulmonary valve and into the pulmonary trunk
Upon return from the lungs blood enters the left atrium moves through the mitral valve and into the left ventricle and through the aortic valve into the aorta and it’s branches

Question 6

Which vessel supply blood to the myocardium

Answer 6

Branches of the coronary artery

Question 7

How does blood return from the cardiac tissues to the right atrium

Answer 7

Through the cardiac vein’s into the coronary sinus

Question 8

Describe the pressure changes in the atria and ventricles

Answer 8

The atria contract while ventricles relax then ventricles contract while atria relax. Then they both relax

Question 9

What causes heart sounds

Answer 9

The lubb is from AV valve closing

Dubb is from aortic valve closing

Question 10

What is a functional syncytium

Answer 10

A mass of merging cells that function as a unit

Question 11

What type of tissues make up the cardiac conduction system

Answer 11

Specialized cardiac muscle tissue who’s fibers contain only a few myofibrils

Question 12

How is cardiac impulse initiated

Answer 12

From the SA node or sinoatrial node

Question 13

How is a cardiac impulse transmitted from the right atrium to the other heart chambers

Answer 13

Sa node
Atrial syncytium
Junctional fibers
AV node
AV bundle
Bundle branches
Purkinje fibers
Ventricular syncytium

Question 14

How do you parasympathetic and sympathetic impulses help control heart rate

Answer 14

Parasympathetic fibers slow heart rate while sympathetic fibers increased heart rate and force of contractions

Question 15

How do you changes in the body temperature affect heart rate

Answer 15

Rise in body temperature increased rate low body temperature decreases heart rate

Question 16

Describe the effects on the heart of abnormal concentrations of potassium and calcium ions

Answer 16

Excess potassium decreases the rate and force of contractions. potassium deficiency can cause life-threatening arrhythmia
Excess calcium increases heart action and extended heart contraction, low calcium depresses heart action

Question 17

Describe the wall of an artery

Answer 17

Arteries are strong elastic vessels that consist of three distinct layers. The innermost layer called the Tunica interna is epithelial tissue. The tunica media is muscle. The tunica externa is thin connective tissue

Question 18

What is the function of smooth muscle in the arterial wall

Answer 18

They are necessary for vasoconstriction and vasodilation

Question 19

How is the structure of an arteriolar different from that of an artery

Answer 19

They have three layers similar to arteries however they are much more thin

Question 20

Describe a capillary wall

Answer 20

They are composed of endothelium the same as the inner layer of an artery

Question 21

What is the function of the capillary

Answer 21

They’re thin walls allow the transfer of substances in the blood with substances in the tissue fluid surrounding body cells

Question 22

What controls blood flow into capillaries

Answer 22

Precapillary sphincter’s

Question 23

Where is the heart located

Answer 23

The heart is in the mediastinum, bordered laterally by the lungs, posteriorly by the vertebral column, and anteriorly by the sternum

Question 24

Which forces affect the exchange of substances between blood and tissue fluid?

Answer 24

Diffusion, filtration, and osmosis

Blood pressure

Question 25

Why is the fluid movement out of a capillary greater at its arteriolar end than at its venular end?

Answer 25

Because pressure is greater at the venular end

Question 26

How does the structure of a vein differ from that of an artery?

Answer 26

Veins have three distinct layers similar to arteries. However, the middle muscle layer is poorly developed. Lumens have a greater diameter. Many have flap like valves.

Question 27

How does venous circulation help maintain blood pressure when hemorrhaging causes blood loss.

Answer 27

Veins are stimulated to contract, which maintains blood pressure and returns more blood to the heart.

Question 28

What is blood pressure?

Answer 28

The force blood exerts against the inner walls of blood vessels

Question 29

Distinguish between systolic and diastolic blood pressure.

Answer 29

Systolic- max pressure during ventricular contraction | Diastolic- lowest pressure that remains at the end of ventricular relaxation.

Question 30

What causes a pulse in an artery?

Answer 30

Surge of blood flow throw a vein distends the wall. Once it's passed through, the wall recoils. The expand and contract is felt as the pulse.

Question 31

How is cardiac output and blood pressure related.

Answer 31

Volume discharged/ minute = cardiac output, it directly corresponds to blood pressure.

Question 32

How does blood volume affect blood pressure?

Answer 32

Directly proportional

Question 33

What is the relationship between peripheral resistance and blood pressure? Between blood viscosity and blood pressure?

Answer 33

Peripheral resistance is conversely related. | Viscosity is conversely related.

Question 34

What factors affect cardiac output?

Answer 34

The volume of blood entering the ventricle

Question 35

What is the function of baroreceptors in the walls of the aorta and carotid arteries?

Answer 35

They sense changes in blood pressure and send info the the medulla oblongata for regulatory action.

Question 36

How does the vasomotor center control peripheral resistance?

Answer 36

It continually sends sympathetic impulses to smooth muscles in the arteriole walls, keeping them in a state of tonic contraction.

Question 37

What is the function of venous valves?

Answer 37

Venous valves keep blood from moving backward.

Question 38

How do skeletal muscles and respiratory movements affect venous blood flow?

Answer 38

skeletal muscles press on veins moving blood from one valve section to another. Respiratory movements also move venous blood due to changes in the diaphragm squeezing blood out of abdominal veins.

Question 39

What factors stimulate venoconstriction?

Answer 39

When venous pressure is low, sympathetic reflexes stimulate venoconstriction.

Question 40

Distinguish between the pulmonary and systemic circuits of the cardiovascular system.

Answer 40

Pulmonary consists of vessels that carry blood from the heart to the lungs and back to the heart. Systemic carries blood from the heart to the whole body.

Question 41

Trace the path of blood through the pulmonary circuit from the right ventricle.

Answer 41

right ventricle - pulmonary trunk - right and left pulmonary arteries - right and left lungs -left atrium.