Circulatory System

Question 1

Human Heart

Answer 1

Divided into left and right side pumps, each pump has two chamber

Question 2

Atrium and Ventricles

Answer 2

Chambers of the heart

Question 3

Pulmonary circuit

Answer 3

Right side of the heart that pumps blood to the lungs

Question 4

Systemic Circuit

Answer 4

Left side of the heart that pumps blood to the body

Question 5

Systole

Answer 5

Ventricle contraction

Question 6

Diastole

Answer 6

Period between contractions

Question 7

Pressure in systemic arteries

Answer 7

~120/80 mm Hg

Question 8

Pressure in pulmonary arteries

Answer 8

~20/10 mm Hg, less pressure than systemic because only going to the lungs, not the top of the head, right ventricle does less work, not as muscular

Question 9

Heart

Answer 9

Striated, multinucleate, branched and involuntary

Question 10

Heart Beat

Answer 10

Normally originates from spontaneous APs generated by SA node in the right atrium

Question 11

Electrical Synapses

Answer 11

Gap junctions, carry APs throughout the heart

Question 12

Firing rate of SA Node

Answer 12

Increased by sympathetic, decreased by parasympathetic

Question 13

Generation of transmission of heart beat

Answer 13

SA node AP spreads through atria causing contraction, AP reaches AV node at the bottom of the atria and it fires

Question 14

Bundle of His

Answer 14

Conducts AP to ventricles, splitting into the right and left bundle branches, become Purkinje fibers in walls of ventricles

Question 15

Conduction Sequence of Heart Beat

Answer 15

SA->AV->bundle of His->R/L bundle branches->Purkinje’s->ventricle contraction, all or nothing

Question 16

Heart Valves

Answer 16

1 way valves that ensure that the blood flows in one direction through the heart

Question 17

Tricuspid Valve

Answer 17

Between right atrium and ventricle

Question 18

Bicuspid or Mitral Valve

Answer 18

Between left atrium and ventricle

Question 19

Papillary Muscles

Answer 19

Hi pressure of ventricle contraction is prevented from everting valves by contraction of these which are connected to valves by chorda tendinea

Question 20

Similunar valves

Answer 20

During ventricle contraction blood is pumped out of the heart through aortic and pulmonary ______

Question 21

Arteries

Answer 21

Transport blood to capillaries, contain 16-18% of blood, control blood flow to tissues via constriction of smooth muscle sphincters at end of their arterioles

Question 22

Capillaries

Answer 22

Perform gas/nutrient exchange, contain 5-7% of blood, at any time only 30-50% of caps are open, only 5-10% caps are open in skeletal muscle cells

Question 23

Veins

Answer 23

Return blood to the heart from capillaries, contain 50-70% of blood and thus serve as a reservoir

Question 24

One way pocket valves

Answer 24

Mainly activity of blood muscles move blood in veins towards the heart because of these

Question 25

ANS

Answer 25

Operates under a priority system to control blood pressure

Question 26

What happens if blood pressure drops?

Answer 26

Sympathetic stimulates constriction of peripheral arterioles and stimulates heart to be faster and harder, can double blood pressure in 5-15 seconds

Question 27

Local Control

Answer 27

Matches blood flow to local needs by opening capillary beds in active tissues

Question 28

What happens in response to local control?

Answer 28

Arteriole sphincters open in response to products of hi tissue activity such as hi CO2 and lactic acid or low O2

Question 29

Heavy exercise

Answer 29

Increases blood pressure and doubles blood flow to active muscles via sympathetic and local control affects

Question 30

Why do athletes warm up before athletic performance?

Answer 30

It opens the capillary beds in exercising muscles, at rest only 5-10% of skeletal muscles capillaries are open