Lexture 10- Anatomy Of The Heart

Question 1

What does the right side of the heart do?

Answer 1

receives deoxygenated blood returning from body tissues and pumps it to the lungs to release CO2 and pick up O2.

This is called the pulmonary circuit.

Question 2

What does left side of the heart do?

Answer 2

receives oxygenated blood from the lungs and pumps it out to the body to supply oxygen to tissues.

This is called the systemic circuit.

Question 3

Where is the heart situated?

Answer 3

In the mediastium ( space between the lungs) and two thirds is left of the midsternal line

Question 4

Fibrous pericardium

Answer 4

Outside wall

protects the heart, anchors it to surrounding structures, and prevents the heart from overfilling.

Question 5

Serous pericardium

Answer 5

double-walled serous membrane, consisting of a parietal layer that lines the inside of the pericardium, and a visceral layer (epicardium) that covers the surface of the heart.

Question 6

Pericardial cavity

Answer 6

Between visceral and parietal layers

containing a film of serous fluid that lubricates their movement against each other.

Question 7

What is the Myocardium composed of?

Answer 7

mainly of cardiac muscle and forms bulk of heart

Question 8

Endocardium

Answer 8

Epithelial tissue that lines chambers of the heart

Continuous with the endothelial linings of the vascular system

Question 9

Right and left atria

Answer 9

Recieving chambers of heart

Minimally contract to propel blood into ventricles

Question 10

What are the three veins that enter the right atrium?

Answer 10

Superior vena cava and inferior vena cava which return blood from body

Coronary sinus which return blood from myocardium

Question 11

Ventricles

Answer 11

Pump blood out of heart

Question 12

Right ventricle

Answer 12

Pumps blood to pulmonary trunk which branches to pulmonary arteries to take blood to lungs

Question 13

Left ventricle

Answer 13

Pumps blood into aorta with many branches to carry blood throughout body

Question 14

Interstitial septum

Answer 14

Divides atria

Question 15

Interventricular septum

Answer 15

Divides ventricles

Question 16

Why is left ventricle wall thicker?

Answer 16

Allowing it to generate a much higher pressure, so that the force can overcome the much greater resistance in the systemic circulation.

Initially it works harder

Question 17

What are the two atrioventricular valves?

Answer 17

Tricuspid (right) and bicuspid (left)

When heart relaxed, hang loosely

When contracted, blood forced upward against valves pushing them closed

Question 18

Chordate tendonae

Answer 18

Attach atrioventricular ventricles to papillary muscles

Prevent Eversion of valves into atria

Question 19

Aortic and pulmonary semilunar valves

Answer 19

located at base of the arteries exiting the heart and prevent backflow of blood into the ventricles.
When ventricular pressure rises, the semilunar valves are forced open allowing blood to be ejected from the heart.

When the ventricles relax, blood flows backward toward heart, filling the cusps of the semilunar valves, forcing them closed

Question 20

Where are there no valves in the heart?

Answer 20

Entrances of vena cava or pulmonary veins

Question 21

Flow of blood through heart

Answer 21

Deoxygenated blood In through superior vena cava/inferior vena cava to right atrium

Pass through tricuspid valve to right ventricle to pulmonary trunk To lungs

Oxygenated blood Enters in through pulmonary veins into left atrium

Pass through bicuspid valve to left ventricle through aortic semilunar valve and exit through aorta to rest of body

Question 22

What is the function of coronary circulation or coronary vessels?

Answer 22

Supply blood and nutrients to heart itself

Question 23

Myocardial infarction (heart attack)

Answer 23

blockage of blood flow to the coronary blood vessels.

Because cardiac muscle does not regenerate, any damage caused by a temporary lack of oxygen results in fibrosis (scarring) and a permanent reduction in heart function.