Cardiovascular (circulatory) system

Question 1

what is the function of the circulatory system?

Answer 1

transport

Question 2

what is the main transport medium of the circulatory system?

Answer 2

blood

Question 3

list the 3 components of the circulatory system

Answer 3

blood, arteries, veins

Question 4

describe the heart

Answer 4

cone-shaped, hollow muscular structure

Question 5

what is the base of the heart?

Answer 5

where the heart attaches to other structures

Question 6

what is the apex of the heart?

Answer 6

the free side of the heart, the point of the cone

Question 7

which side of the heart sits more cranially and which is more caudal?

Answer 7

the right side is more cranial, the left side is more caudal

Question 8

what does the heart sit within? how many layers does that thing have?

Answer 8

a protective layer called the pericardium, which has two layers

Question 9

list and describe the 2 layers of the pericardium including their tissue types

Answer 9

1. parietal pericardium: outer layer, dense irregular connective tissue
2. visceral pericardium: inner layer, fused to muscle of heart, thin layer of simple squamous epithelium

Question 10

what is the pericardial space? what is it filled with and what is its function?

Answer 10

the space between the parietal and visceral pericardium, filled with pericardial fluid, reduces friction

Question 11

how many layers does the heart wall have? list them

Answer 11

3

outer layer, myocardium, inner layer

Question 12

describe the outer layer of the heart wall, including 2 alternate names and the tissue type

Answer 12

also called epicardium, is the same thing as the visceral pericardium, simple squamous epithelium

Question 13

describe the myocardium layer of the heart wall, including tissue type and describe thickness

Answer 13

middle layer, thickest, made of cardiac muscle tissue, thicker on left side than right side

Question 14

describe the inner layer of the heart wall, including an alternate name and tissue type

Answer 14

also called endocardium, simple squamous epithelium

Question 15

list and describe the 2 types of heart chambers

Answer 15

Atria: (L & R), receive blood from veins
Ventricles: pump blood into arteries

Question 16

list and describe the 2 broad types of heart valves

Answer 16

Atrioventricular valves: separate atria from ventricles

Semilunar valves: separate ventricles from arteries

Question 17

list and give the location of the 2 types of atrioventricular valves

Answer 17

1. tricuspid valve: separates right atrium from right ventricle
2. mitral (bicuspid) valve: separates left atrium from left ventricle

Question 18

list and give the location of the 2 types of semilunar valves

Answer 18

1. pulmonary valve: separates right ventricle from pulmonary artery
2. aortic valve: separates left ventricle from aorta

Question 19

what is the ventricular septum?

Answer 19

a layer of myocardium that separates the left and right ventricles

Question 20

describe the path of blood flow through the heart, beginning with the right atrium

Answer 20

deO2 blood flows from the right atrium through the tricuspid valve into the right ventricle, then through the pulmonary valve, out the pulmonary artery to the lungs, where gas exchange occurs. O2 blood flows back in through the pulmonary vein into the left atrium, through the mitral valve into the left ventricle, then through the aortic valve out the aorta to the body, where O2 is delivered. DeO2 blood then flows in through the vena cavae (superior, or cranial, and inferior, or caudal) back into the right atrium

Question 21

where are the largest blood vessels located?

Answer 21

by the heart

Question 22

list the flow of blood vessels from largest to smallest and back to largest

Answer 22

heart –> arteries –> arterioles –> capillaries (smallest) –> venules –> veins —> heart

Question 23

what can fit through a capillary?

Answer 23

only one line of cells at a time, very tiny

Question 24

list the 2 main circulatory systems

Answer 24

1. pulmonary circulation

2. systemic circulation

Question 25

describe pulmonary circulation

Answer 25

transports deoxygenated blood from the heart to the lungs, and oxygenated blood from the lungs to the heart

Question 26

describe systemic circulation

Answer 26

transports oxygenated blood from the heart to the body (except the lungs) and deoxygenated blood from the body to the heart

Question 27

what is coronary circulation?

Answer 27

the vascular system of the heart

Question 28

what do portal systems do? how?

Answer 28

depart from normal circulation, a vein reforms a capillary bed in another tissue before returning blood to the heart

Question 29

describe cardiac muscle cells

Answer 29

mono-/di- nucleated, striated, with the sarcomere as the basic contractile unit, have intercalated disks that connect the cells

Question 30

describe cardiac muscle cells as they relate to contraction of the heart

Answer 30

the intercalated disks that connect them allow for transfer of the action potential between cells, where every individual cell no longer needs the stimulus to contract, instead the stimulus can be passed along through the disks

Question 31

list the 8 steps of transmission of an action potential throughout the heart

Answer 31

1. pacemaker cells in the sinoatrial (SA) node in the right atrium simultaneously generate action potentials 2. action potential will spread throughout atria due to intercalated disks 3. atria contract 4. atrioventricular (AV) node in right atrium transmits action potential to bundle of His (in center of heart) 5. bundle of His branches off into right and left bundle branches which transmit the action potential down the ventricular septum and around ventricles 6. right and left bundle branches branch out into Purkinjie fibers, which transmit the action potential to cardiac muscle cells of ventricles 7. action potential spreads across ventricles via intercalated disks 8. ventricles contract

Question 32

what is the cardiac cycle?

Answer 32

the sequence of events that occur during one complete heart beat

Question 33

list and describe the 2 steps of the cardiac cycle

Answer 33

1. diastole: relaxation of ventricles, atria are contracting and pushing blood through AV valves into ventricles 2. systole: contraction of ventricles, blood is being pushed through semilunar valves into arteries, atria are relaxed and filling with blood from vena cavae or pulmonary vein

Question 34

which step of the cardiac cycle is the "lub" sound?

Answer 34

systole

Question 35

which step of the cardiac cycle is the "dub" sound?

Answer 35

diastole

Question 36

describe heart rate

Answer 36

frequency of cardiac cycles in one minute, measured in beats per minute (bpm)

Question 37

what determines heart rate (2)

Answer 37

animal body size, corresponds with life expectancy

Question 38

what is blood pressure?

Answer 38

the force applied to artery walls, measured in (systolic/diastolic) systolic should be a bigger number