2.2.3. Describe the anatomy of the heart with reference to the heart chambers, valves and major blood vessels

Capillary

Function: Carry food/ oxygen to tissues and carry waste awar Structure: thin network to allow substance to diffuse into tissue Lumen: small - only one cell could fit through Structure + Function: Thin walled to allow for easy diffusion into tissue

Veins

Function: Transportation of deoxygenated blood to the heart (except pulmonary vein) Structure: 1 outer layer (tunica adventitia) + elastic tissue Lumen: Large - less muscle to allow for easy blood flow Valves: push blood from high to low pressure segments Structure + Function: Wide lumen for consistent easy flow

Arteries

Function: Transportation of oxygenated blood away from heart (except pulmonary artery) Structure: Thick walled + Elastic fibres and fibrous tissue Lumen: Small - allow for surrounding muscle for pressure Structure + Function: More muscle to allow for greater pressure within the artery to push to body

Valves - Tricuspid

•Boundary between right ventricle and atrium. •Has three valves

Valves - Aortic

•Closes off the lower chamber that holds the blood before it is pumped.

Blood Vessels - Pulmonary Vein

•Large blood vessels that receive oxygenated blood from the lungs and drains into the left atrium of the heart.

Blood Vessels - Vena Cava

•Large vein that carries the de-oxygenated blood from the lower body to the heart.

Blood Vessels - Aorta

•Largest artery in the body •Begins at the top of the left ventricle •Blood is pumped from left ventricle into the aorta throughout the aortic valve.

Four Chambers - Artia

•Receives blood returning to the heart and pushes through to ventricles via valves. •Thin walled

Valves - Bicuspid

•Situated between the left atrium and left ventricle •Two flaps (cusps) commonly referred to as mitral valve.

Four Chambers - Ventricles

•To pump blood to the entire body. •Right ventricle receives blood via right atrium and pushes blood through the lungs to be oxygenated. •Left ventricle has thicker muscle wall to provide a greater flow of blood to body.

Blood Vessels - Pulmonary Artery

•Transports de-oxygenated blood from the right ventricle to the lungs.

Valves - Pulmonary Valve

•Valve that increases blood pressure to push blood into the artery. •Closes when the pressure drops •In right ventricle of heart.