Cardiovascular System Part 1

Question 1

The mammalian heart

Answer 1

1) BLOOD PUMPED OUT OF RIGHT VENTRICLE AND THROUGH PULMONARY SEMILUNAR VAVE
2) Blood travels through pulmonary arteries to lungs
3) Gas exchange occurs in capillary beds of lungs
4) Blood returns to heart through pulmonary veins and enters left atrium, passes through left AV valve
5) Then into left ventricle, which pumps blood through aortic semilunar valve and into the aorta
6) The aorta distributes blood to upper and lower body
7-8) Gs exchange occurs in the capillary beds of the bodys tissues
9) Blood returns to the heart through the superior, inferior vena cava, and enters heart in right atrium

Question 2

Heart consists of…

Answer 2

Muscle cells bound to a fibrous tissue

-Skeleton consists of valves and associated structures

Question 3

The fibrous skeleton provides three main functions

Answer 3

1) Structural support for the heart
2) Gives the muscle cells something to pull against
3) Electrical insulation that helps regulate the heart beat

Question 4

Intercalated discs consists of two parts…

Answer 4

Desmosomes and gap junctions

Question 5

Desmosomes

Answer 5

• Provide a physical connection

- Allows muscle cells to pull on each other without damaging membrane

Question 6

Gap Junctions

Answer 6

-Provide cytoplasmic connection between cells

Question 7

Arteries

Answer 7

Carry blood away from heart

Question 8

Veins

Answer 8

Carry blood toward heart

Question 9

Oxygen rich heart anatomy

Answer 9

Aorta, left atrium, left ventricle, pulmonary veins

Question 10

Oxygen poor heart anatomy

Answer 10

Superior vena cava, right atrium, right ventricle, interior vena cava, pulmonary artery

Question 11

Concepts of volume and pressure

Answer 11

• For a fixed volume of fluid, pressure depends on the volume of the space it occupies
• Pressure and volume are inversely proportional
• –Think of heart chambers as a space containing a fluid
• Volume of chambers change during a heartbeat
• Fluid flows from high pressure to low pressure as long as the path is not blocked

Question 12

Systole

Answer 12

• Contraction

- Space of the chamber decreases, volume of fluid is same

Question 13

Diastole

Answer 13

• Relaxation

- Space of the chamber increases, volume of fluid is same

Question 14

The cardiac cycle

Answer 14

One complete contraction and relaxation

Question 15

Heart beat is coordinated

Answer 15

-First atria contract together, then ventricles contract together

Question 16

All chambers in diastole

Answer 16

• Blood flows passively through atria and into ventricles
• Both AV valves open
• Note both atria and ventricles fill with blood
• But not all blood leaves atria

Back
-As ventricles enter diastole, a little blood sucked back in; however, right and left semilunar valves snap shut (Second heart sound)

Question 17

Atrial systole

Answer 17

• Contraction

- ventricles (still diastole) swell with extra blood that has been pumped in by atria

Question 18

Ventricular systole (atrial diastole)

Answer 18

• Right and left AV valves pushed shut (first heart sound)
• Blood forced into arteries through pulmonary and aortic semilunar valves
• Keep in mind that ventricles need to contract from the bottom up