The heart

Question 1

Septum

Answer 1

a walk of muscle with separate the heart into 2 parellel pumps each with an atrium and ventricle

Question 2

Artria

Answer 2

located at the top of the heart. Receive blood and pump it into the ventricles

-Right atrium: receives deoxygenated blood from the body
-Left atrium: receives oxygenated blood from the lungs

Question 3

Ventricles

Answer 3

Located at the bottom of the heart
-The right ventricle pumps blood to the pulmonary circuit
-The left ventricle pumps blood to the systemic circuit

Question 4

The heart is surrounded by a

Answer 4

pericardium

-fluid filled membrane
-protects heart from friction with other tissues and organs in the chest cavity as the heart beats

Question 5

The heart requires 10% of oxygen that’s in blood

Question 6

Heart has its own supply of blood vessles called…

Answer 6

coronary blood vessels
-They provide the hearts muscle cells with oxygen and nutrients and remove waste products

Question 7

The muscular walls of the ventricles are much thicker than the atria this is because…

Answer 7

The ventricles have to pump blood over greater distances than the atria

Question 8

Circulation

Answer 8

at rest the heart can pump 5L per min

at max output it can pump 25L per min

Question 9

Steps in circulation

Answer 9

Step 1: deoxygenated blood enters right atrium through the inferior and superior vena cava
Step 2: right atrium contracts—> blood forced into right ventricle
Step 3: Right ventricle contracts forcing blood through the pulmonary arteries to the lungs where it picks up oxygen and releases CO2
Step 4: oxygenated blood from the lungs enters left atrium from the pulmonary veins
Step 5: left atrium contracts contracts and forced blood into left ventricle
Step 6: left ventricle contracts and forces blood through the aorta
Step 7: aorta branches out into major arteries that circular blood to body
step 8: arteries—> capillary networks—>veins—>inferior and superior vena cava

Question 10

Valves

Answer 10

-Semilunar valves: located between left ventricle and aorta as well as right ventricle and pulmonary artery which prevent back flow of blood when ventricles relax
-Atrioventricular valves: located between atria and ventricles and prevents blood from flowing back into atria when ventricles contract
*they’re subject to high pressure and therefore have chordae tendineae which are tendons that support the AV valves

Question 11

Arteries

Answer 11

-Take blood away from the heart
-Mostly carry oxygenated blood(except for pulmonary artery)
-The largest artery is the aorta
-Arteries are elastic and the middle layer of an artery wall consists of smooth muscles that can construct to regular blood flow and blood pressure

Question 12

Veins

Answer 12

-Venuals drain blood from capillaries, then join to form veins that take blood to the heart
-Veins have much less smooth muscle and connective today than arteries
-Veins often contains sets of one way valves, venous valves, that prevent the backward flow of blood when closed
-Contraction of skeletal muscles squeezes the veins pushing blood up towards the heart