Cardiorespiratory System

Question 1

Cardiorespiratory System

Answer 1

Primary purpose is to deliver adequate amounts of oxygen, remove wastes from body tissues, and to maintain carbon dioxide homeostasis in body tissues (15-25 times greater oxygen demand during exercise)

Question 2

To meet oxygen demands of muscle during exercise the two major adjustments that must be made are:

Answer 2

1) Increased Cardiac Output

2) Redistribution of blood flow from inactive organs to active skeletal muscles

Question 3

Circulatory System/Cardiovascular

Answer 3

Transports O2 and nutrients to tissues, removal of CO2 and waste from tissues, regulation of body temperature

Question 4

Respiratory System

Answer 4

Adds oxygen and removes carbon dioxide from the blood; Plays an important role in the regulation of acid-base balance during heavy exercise

Question 5

Heart

Answer 5

Creates pressure to pump blood

Question 6

Arteries and Arterioles

Answer 6

Carry blood away from the heart

Question 7

Capillaries

Answer 7

Exchange of O2, CO2, and nutrients between tissues; Oxygen is being used as final electron acceptor at the end of the electron transport chain, CO2 is byproduct of cellular metabolism and is used to make bicarbonate (major buffer of acidity), nutrients include glucose, amino acids, and lipids

Question 8

Veins and Venules

Answer 8

Carry blood toward the heart

Question 9

AVO2 Difference

Answer 9

Difference in oxygen tension between arteries and veins (How much oxygen is extracted from blood); 20-25% extracted during rest, 80-85% during work

Question 10

Pulmonary Circuit

Answer 10

(Low Pressure Circuit) 25/5 mmHg; Right side of the heart, Pumps deoxygenated blood to the lungs via pulmonary arteries, Returns oxygenated blood to the right side of the heart via pulmonary veins

Question 11

Systemic Circuit

Answer 11

(High Pressure Circuit) 120/80 mmHg; Left side of the heart, Pumps oxygenated blood to the whole body via arteries, Returns deoxygenated blood to the right side of the heart via veins

Question 12

Which circuit (side of the heart) has less pressure?

Answer 12

Lower in Pulmonary Circuit (Right side of the heart) because it has Smaller blood volume, Shorter Vessels, Thinner walls, Less resistance to flow

Question 13

Which side of the heart has thinner myocardial walls?

Answer 13

Right walls are thinner, left walls are thicker to send to entire systemic circuit

Question 14

Pathway of Blood

Answer 14

Right Atrium> Tricuspid Valve> Right Ventricle> Pulmonary Semilunar Valve> Pulmonary Arteries> Lungs> Pulmonary Veins> Left Atrium> Mitral Valve> Left Ventricle> Aortic Semilunar Valve> Aorta> Arteries> Arterioles> Capillaries> Venules> Veins> Inferior and Superior Vena Cava> Back to RA

Question 15

Epicardium/Visceral Pericardium

Answer 15

(fibrous and adipose tissue) serous membrane including blood capillaries, lymph capillaries, and nerve fibers (external); Lubricative pericardial sac/fluid prevents generation of friction and heat around heart

Question 16

Myocardium

Answer 16

(muscle) Cardiac muscle tissue separated by connective tissues and including blood capillaries, lymph capillaries and nerve fibers
Muscular portion of heart wall that provides contractions that eject blood from heart chambers

Question 17

Endocardium

Answer 17

Endothelial Wall) Endothelial tissue and a thick sub-endothelial layer of elastic and collagenous fibers (continuous with endothelial of the blood vessels); Serves as a protective inner lining of the chambers and valves

Question 18

Myocardial thickness

Answer 18

The thicker the muscle or the more hypertrophy the muscle, the greater the pressure it can exert; thicker part should be associated to the part that has to push the furthest (systemic circuit)

Question 19

Myocardial Hypertrophy=

Answer 19

Not Safe; occurs due to high resistance at aorta or peripheral arteries (scarred arteries)

Question 20

Thickness of Myocardium

Answer 20

RA: 1-2mm, RV: 3-5mm, LA: 3-5mm, LV: 8-12mm

Question 21

How myocardial perfusion needs met

Answer 21

The myocardium receives blood supply via the right and left coronary arteries which branch off the aorta and encircle the heart, when this blood flow is disrupted it can cause permanent damage to the heart; This injury results in the death of cardiac muscle cells and is known as a heart attack or myocardial infarction (The number of heart cells that die determines the severity of the heart attack)

Question 22

Myocardial Infarction

Answer 22

Heart is protected by exercise training during it and myosin isoform changes

Question 23

R & L Ventricle

Answer 23

Pressure Generation; Myocardium = Thickness Varies

Question 24

Aorta & Large Arteries

Answer 24

Pressure Storage 
Increase Elastin (recoil)

Question 25

Small Arteries & Arterioles

Answer 25

Resistance Vessels

Less Elastin, More Circular Smooth Muscle

Question 26

Veins

Answer 26

Volume Storage

Little Elastin or Smooth Muscle, Thin Walls