Lab test 2: 30

Question 1

What is the function of the fluid that fills the pericardial sack

Answer 1

Allows the heart to beat in a relatively frictionless environment

Question 2

Location of the heart in the thorax

Answer 2

mediastinum

Question 3

Superior heart chambers

Answer 3

Atria

Question 4

Inferior heart chambers

Answer 4

Ventricles

Question 5

Visceral pericardium

Answer 5

Endocardium

Question 6

recieving chambers of the heart

Answer 6

Atria

Question 7

Equals cardiac muscle

Answer 7

myocardium

Question 8

Lining of the heart chambers

Answer 8

endocardium

Question 9

Actual “pumps” of the heart

Answer 9

myocardium

Question 10

Drains blood into the right atrium

Answer 10

Coronary sinus

Question 11

What is the function of the valves found in the heart

Answer 11

Enforce a one way blood blow. Prevent back flow

Question 12

What is the role of the chordae tendinae

Answer 12

Anchor the cusps to the ventricular wals

Question 13

What is missing from the diagram

Answer 13

Pulmonary circulation

Question 14

First diagram

Answer 14

Pulmonary circulation

Question 15

Second diagram

Answer 15

Systemic circulation

Question 16

Differntiate clearly between the roles of the pulmonary and systemic circulations

Answer 16

Pulmonary circulation provides gas exchange in the lungs. Systemic circulation provides the functional blood supply to all body tissues

Question 17

If the mitral valve does not close properly, which circulation is affected

Answer 17

Pulmonary circulation

Question 18

Why might a thrombus (blood clot) in the anterior descending branch of the left coronary artery cause sudden death

Answer 18

A thrombus in the coronary artery can cut off the blood supply to the heart, resulting in rapid beath

Question 19

How would you distinguish a structure of cardiac muscle from that of skeletal muscle

Answer 19

Skeletal is long, cylindrical multinucleated cells that have obvious striations

Cardiac muscle are branched, striated, unnucleated cells that connect at junctions

Question 20

Unique anatomical features of cardiac muscles

Answer 20

Intercalated discs hold cells together so they do not pull apart when the heart contracts and allow electrical connection between cells.

Many mitochondria that provide the energy required for contraction

Question 21

What differences did you observe between the two chambers (LV and RV)

Answer 21

LV felt thick and solid. Right felt thinner, easily moved and flabby

Question 22

Which ventricle was thicker

Answer 22

Left ventricle

Question 23

How would you say the structural difference between the LV and RV reflects the relative functions of these two heart chambers

Answer 23

There is a greater demand on the longer systemic circulation (LV) and has higher restistance than the pulmonary circulation (RV)

Question 24

Semilunar valves prevent backflow into the _______: mitral and trisuspud valves prevent backflow into the ______

Answer 24

Ventricles

Atria

Question 25

Explain how the operation of the semilunar valves differs from that of mitral and tricuspid valves

Answer 25

The mitral valve allows blood to flow from the LA to the LV. Tricuspid valve stops backflow between the two. Semilunar valves permit blood to be forced into the arteries but prevent backflow of blood from the arteries into ventricles

Question 26

Compare and contrast the structure of the mitral and tricuspid valves

Answer 26

Mitral: 2 flaps
Tricuspid: 3

Question 27

Ligamentum anteriosum

• name in fetal heart
• location
• common purpose

Answer 27

• ductus anteriosus
• located between the pulmonary trunk and aortic arch

-allows blood to flow from pulmonary trunk to systemic circulation

Question 28

Fossa ovalis

• name in fetal heart
• location
• common purpose

Answer 28

• Foramen ovale
• on right atrium wall
• allowed blood to enter the left atrium from the right atrium