Heart

Question 1

What is the heart responsible for maintaining?

Answer 1

constant supply of fresh oxygen and nutrients to the body’s tissue while removing carbon dioxide and waste

Question 2

Right side of the heart

Answer 2

receives oxygen-poor blood and pumps it to the lungs (pulmonary circuit)

Question 3

Left side of the heart

Answer 3

receives oxygen-rich blood and pumps it to the body (systemic circuit)

Question 4

Two Atria

Answer 4

The receiving chambers

“little hallway”

Question 5

Right Atrium

Answer 5

receives blood returning from the systemic circuit

Question 6

Left Atrium

Answer 6

receives blood returning from the lungs

Question 7

Two Ventricles

Answer 7

The pumping Chambers

“little belly”

Question 8

Right Ventricle

Answer 8

pumps blood into pulmonary circuit

Question 9

Left Ventricle

Answer 9

pumps blood into the systemic circuit

Question 10

Location of heart

Answer 10

Size = human fist

Between sternum and vertebral column

Rests on diaphragm

2/3 of the heart’s mass is to the left of the midsternal line

Question 11

Pericardium

Answer 11

double-walled sac that encloses the heart

Question 12

Fibrous Pericardium

Answer 12

loose fitting superficial part of the pericardium

• dense connective tissue
• protects heart, keeps it from overfilling, anchors it to the mediastinum

Question 13

Serous Pericardium

Answer 13

deep to the fibrous pericardium, made of 2 thin layers

• Parietal layer
• Visceral layer

Question 14

Parietal Layer

Answer 14

lines the internal surface of the fibrous pericardium

Question 15

Visceral layer

Answer 15

lines the external surface of the heart

Question 16

Pericardial Cavity

Answer 16

space between the parietal + visceral layers, filled with serous fluid

• reduces friction

Question 17

Pericarditis

Answer 17

inflammation of the pericardium

• beating heart rubs against the pericardial sac - an audible sound produced

Symptom- pain deep to sternum

• can lead to adhesions, impeded cardiac activity

Question 18

Cardiac Tamponade

Answer 18

compression of the heart by large amounts of inflammatory fluid in the pericardial cavity

• heart’s ability to pump blood is reduced
• Management_ removal of excess fluid by syringe

Question 19

Layers of heart

Answer 19

• Epicardium
• Myocardium
• Endocardium

Question 20

Epicardium

Answer 20

most superficial

Question 21

Myocardium

Answer 21

middle muscle layer

• composed of contracting, cardiac muscle; bulk of heart
• cardiac muscle cells are arranged in spiral bundles, tethered together by crisscrossing connective tissue (tissue important for sending signals)

Question 22

Cardiac Skeleton

Answer 22

a reinforcing, dense network formed by the connective tissue fibers

• prevents overstretching from continuous stresses and ensures that action potential only spread along desired pathways

Question 23

Endocardium

Answer 23

deepest layer, made of endothelium

• line heart chambers, contiguous with the lining of the great vessels

Question 24

How many chambers, atria, and ventricles are there?

Answer 24

4 chambers
2 superior atria
2 inferior ventricle

Question 25

Coronary Sulcus (atrioventricular groove)

Answer 25

encircles the junction of the atria and ventricles

Question 26

Anterior Interventricular Sulcus

Answer 26

carries the anterior interventricular artery, marks the interventricular septum

Question 27

Posterior Interventricular sulcus

Answer 27

carries the psoterior interventricular artery, marks the interventricular septum

Question 28

Auricles

Answer 28

small, wrinkled appendages that sit atop each atrium - expand the volume capacity of the right and left atria as needed

Question 29

Atria

Answer 29

small, receiving chambers; generate only minimal contraction to push blood into the ventricles - anterior wall of right atrium is covered with pectinate muscle - left atrium's wall are smooth

Question 30

blood enters the right atrium via...

Answer 30

Coronary Sinus Superior Vena Cava Inferior Vena Cava

Question 31

Blood enter the left atrium via...

Answer 31

Pulmonary veins (4)

Question 32

Ventricles

Answer 32

makes up most of the volume of the heart - left ventricle wall is 3x thicker than right ventricles - left ventricle is circular while right is crescent shaped slide 15..

Question 33

Valves

Answer 33

esnures that blood flowd through the ehart in only one direction atria -> ventricles; ventricles -> great arteries

Question 34

Atrioventricular valves (AV)

Answer 34

located at each atrial-ventricular junction, prevent backflow of blood into the atria during ventricular contraction

Question 35

Tricuspid valve

Answer 35

located between the right atrium and ventricle, has 3 flexible cusps cusps: flap of endocardium

Question 36

Bicupid valve

Answer 36

located between the left atrium and ventricle, has 2 flexible cusps

Question 37

chordae tendinae

Answer 37

... slides 16

Question 38

Functions of valves

Answer 38

blood returning to the atria puts pressure against AV valves; the AV valves are forced opened as the ventricles fill, AV valve cups hang limply into ventricle atria contract, forcing additional blood into ventricles ventricles contract forcing blood against AV valve cusps AV valve close chordae tedinae tighten, preventing valve cusps from everting into atria

Question 39

Simulunar Valves (SL)

Answer 39

- Aortic + Pumonary guard the bases of the large arteries emerging from each of the ventricle, prevents backflow from vessel to ventricle

Question 40

Why do SL Valves open and close in response to what

Answer 40

changes in pressure - forced open as ventricle contact and pressure rises - close as blood backflows toward the heart and dills the cusps

Question 41

slide 20

Question 42

Valve disease/replacement

Answer 42

leaking valves recue the efficiency of pumping heart incompetent/insufficient valves force heart to repump the same blood multiple times stenotic valves are stiff/narrowed, constrict heart's openings (narrowed openings force the heart to contract more forcefully) faulty valves increases heart's workload - heart weakens over time mitral and aortic valves are msot often affected valves can be replaced with mechanical replicas, chemicallt treated pig or cow valves, or cryopreserved cadaver valves