The Heart (Lecture 16)

Question 1

How long does it take to circulate all your blood?

Answer 1

about 1 minute

Question 2

What does the heart serve as a pump for?

Answer 2

the pulmonary and systemic circuits

Question 3

What is the average cardiac output?

Answer 3

5.25 L/min

Question 4

Where is the heart found?

Answer 4

the mediastinum

Question 5

Where does the heart lie?

Answer 5

on the diaphragm and posterior to the sternum

Question 6

Where is the base of the heart?

Answer 6

posterior and superior surface of the heart

Question 7

Where is the apex of the heart?

Answer 7

anterior and inferior, points to the left hip

Question 8

How many layers of the pericardium are there?

Answer 8

three

Question 9

What are the layers of the pericardium?

Answer 9

fibrous, parietal, and visceral pericardium

Question 10

What is the visceral layer also known as?

Answer 10

epicardium

Question 11

What does the pericardial cavity contain?

Answer 11

serous fluid

Question 12

What are the functions of the pericardium?

Answer 12

prevents undesired movement, prevents overfilling of the heart, reduces friction

Question 13

What are the layers of the heart wall?

Answer 13

epicardium, myocardium, endocardium

Question 14

What epithelium is the epicardium made of?

Answer 14

simple squamous

Question 15

What is the epicardium layer of the heart?

Answer 15

visceral layer of serous pericardium

Question 16

What is the myocardium of the heart?

Answer 16

cardiac muscle

Question 17

What makes up the bulk of the heart wall?

Answer 17

myocardium

Question 18

What does the endocardium of the heart do?

Answer 18

lines chambers and covers valves

Question 19

What epithelium is the endocardium made of?

Answer 19

simple squamous epithelium

Question 20

What is the pulmonary circuit?

Answer 20

carries blood to and from the lungs

Question 21

What is the pump for the pulmonary circuit?

Answer 21

right ventricle

Question 22

What is the systemic circuit?

Answer 22

transports blood to and from the body tissues

Question 23

What is the pump for the systemic circuit?

Answer 23

left ventricle

Question 24

Which ventricle is bigger?

Answer 24

left

Question 25

What does the right atrium do?

Answer 25

receives oxygen-poor blood from systemic circuit

Question 26

What does the right ventricle do?

Answer 26

ejects oxygen-poor blood into the pulmonary trunk

Question 27

What is special about the pulmonary valve?

Answer 27

the shape of it allows it to open when the ventricle contracts and prevents blood from returning to the ventricle

Question 28

What does the left atrium do?

Answer 28

receives oxygen-rich blood from lungs through pulmonary veins

Question 29

What does the left ventricle do?

Answer 29

ejects oxygen-rich blood into the aorta

Question 30

What chamber of the heart is the most muscular?

Answer 30

left ventricle

Question 31

What is the structure of the heart valves?

Answer 31

composed of dense connective tissue, two or three cusps

Question 32

What are the functions of the heart valves?

Answer 32

permit passage of blood in one direction, prevent back flow of blood

Question 33

What is the fibrous skeleton of the heart?

Answer 33

dense connective tissue located between the atria and the ventricles

Question 34

What are the functions of the fibrous skeleton of the heart?

Answer 34

separates the atria and ventricles (structurally and electrically), anchors heart valves, provides a framework for cardia muscle attachment

Question 35

What does cardiac muscle tissue look like?

Answer 35

short cells, branched, striated, contain 1-2 nuclei

Question 36

What are cells joined by?

Answer 36

intercalated discs

Question 37

What do gap junctions do for the heart?

Answer 37

increase the flow of electrical current

Question 38

What do desmosomes do for the heart?

Answer 38

prevent cardiac muscle from pulling apart

Question 39

Does skeletal or cardiac muscle have more mitochondria and ATP?

Answer 39

cardiac muscle

Question 40

What is coronary circulation?

Answer 40

brings nutrient and oxygen to the heart wall

Question 41

What does inadequate circulation cause?

Answer 41

heart attack/myocardial infarction

Question 42

What is heart failure?

Answer 42

progressive weakening of the heart

Question 43

What happens during heart failure?

Answer 43

heart can't pump enough blood to meet the needs of the body, ventricles don't empty completely so they become overfilled and blood backs up into veins behind the ventricle

Question 44

What may result from heart failure?

Answer 44

edema (congestion) in tissues outside the pulmonary or systemic circuits