Chapter 7: The Cardiovascular System

Question 1

Starting from entering the heart from the venae cavae, what are thefour chambers through which blood passes in the heart? Which valve prevents backflow into each chamber?

Answer 1

Heart Chamber: Valve that Prevents Backflow

Right Atrium: Tricuspid Valve

Right Ventricle: Pulmonary Valve

Left Atrium: Mitral (Bicuspid Valve)

Left Ventricle: Aortic Valve

Question 2

Starting with the site of impulse initiation, what are the structures in the conduction system of the heart?

Answer 2

Sinoatrial (SA) node -> atrioventricular (AV) node -> bundle of His (AV bundle) and its branches -> Purkinje fibers

Question 3

Answer 3

Question 4

Why does the right side of the heart contain less cardiac muscle than the left?

Answer 4

The right side of the heart pumps blood into a lower-resistance circuit and must do so at lower pressures; therefore, it requires less muscle. The left side of the heart pumps blood into a higher-resistance circuit at higher pressures; therefore, it requires more muscle.

Question 5

If all autonomic input to the heart were cut, what would happen?

Answer 5

If all autonomic intervention to the heart were lost, the heart would continuee beating at the intrinsic rate of the pacemaker (SA Node). The inidividual would be unable to change his or her heart rate via sympathetic or parasympathetic nervous system, but the heart would not stop beating.

Question 6

Mnemonic

Arteries carry bloow ___.

Answer 6

Away from the heart.

Question 7

Pulmonary Circulation

Answer 7

The right side of the heart accepts deoxygenated blood returning from the body and moves it to the the lungs by way of the pulmonary arteries. This consititutes the first pump.

Question 8

Systemic circulation

Answer 8

The second pump is the left side of the heart, whic recieves ocygentaed blood from the lungs by way of the pulmonary veins and forces it out to the body through the aorta.

Question 9

MNEMONIC for Atrioventricular Valves.

Answer 9

LAB RAT

Left Atrium = Bicuspid

Right Atrium = Tricuspid

Question 10

____ is where impulse initiation occurs and doesnt require any neurological input.

Answer 10

SA node

Question 11

____ is where the signal is delayrf to allow the ventricles to fill completely before they contract.

Answer 11

AV node

Question 12

____ is part of the conduction system of the heart; it carries impulses from the AV node to the ventricles.

Answer 12

Bundle of His

Question 13

____ distrbiute the electrical signal through the ventricular muscle.

Answer 13

Purkinje Fibers

Question 14

Cardiac muscle has ____, meaning that it can contract without any neurological input. The SA node generates about ____ beats per minute, even if all innervation of the heart is cut. The neurological input of the heart is important in ____.

Answer 14

• Myogenic activity
• 60-100 beats per minute
• speeding up and slowing down the rate of contraction, but not generating it in the first place.

Question 15

Systole

Answer 15

Ventricular contraction and closure of the AV valves (Tricuspid and Bicupid/mitral) occurs and blood is pumped out the ventricles .

Question 16

Diastole

Answer 16

Ventricles are relaxed, the semilunar valves (Aortic valve and Pulmonic valve) are closed, and the blood from the atria fills the ventricles .

Question 17

Cardiac Output

Define

Equation

Answer 17

• The total blood volume pumped by a ventricle in a minute.
• CO= HR x SV
  
  • HR = Beats per minute
  • SV = Volume of blood pumped per beat

Question 18

What is the largest artery?

Answer 18

Aorta

Question 19

Blood Flow of Heart

Answer 19

Question 20

Hepatic portal system

Hypophyseal portal system

Renal portal system

Answer 20

• blood to liver
• blood leaves hypothalamus to travel to capillary beds i the anterior pituitary to allow for paracrine secretionof releasing hormones.
• blood leaving glomerulus travels through an efficient arteriole before surronding the nephron in a capillary network called the vasa recta