Biology - Circulatory System

Purpose of System

Purpose of System

• Transportation (Oxygen, Heat, Urea, Nutrients, Carbon Dioxide, Hormones)

• Regulates internal temp (heat transportation)

• protects against blood loss (injury, disease-causing microbes)

Main components of System

• Heart: Muscular organ, continuously pumps blood through body and generates blood flow

• Blood Vessels: System of hollow tubes through which blood moves

• Blood: Fluid that transports materials like oxygen, carbon dioxide and nutrients

Chambers: Atria

• On top!

• Right Atrium: Recieves deoxygenated blood from body via superieur or inferior vena cava

• Left Atrium: Recieves oxygenated blood from lungs via pulmonary veins

Chambers: Ventricles

• On bottom

• Right Ventricle: Recieves deoxygenated blood from right atrium, pumps it to pulmonary artery, which takes it to lungs to get oxygen

• Left Ventricle: Recieves oxygenated blood from left atrium, pumps it to aorta, which carries it to body

Septum

Separates left and right chambers of the heart

Vessels of the Heart: Arteries VS Capillaries VS Veins

• Arteries = Carry high blood pressure from heart to tissues. Have thicker muscular layer and tend to be large structures

• Capillaries = Blood moves slowly through them so substances (nutrients, oxygen, carbon dioxide) can be exchanged. Very small, can penetrate almost any tissue

• Veins = Carry low blood pressure back to heart using valves. Thinner than arteries, tend to be large structures

Arteries

• Pulmonary Artery = Deoxygenated blood carried to lungs

• Aorta = Oxygenated blood carried AWAY from heart to rest of body

Veins

• Superior Vena Cava = carries deoxygenated blood from top of body to heart (R atrium)

• Inferior Vena Cava = carries deoxygenated blood from bottom of body to heart (R atrium)

• Pulmonary Vein = Carries oxygenated blood from lungs to L atrium

Valves

Prevent back flow of blood

Coronary Arteries

• Branches of aorta through the heart muscle, that provide oxygen and nutrients to heart muscle cells

• Bc blood passing through heart do this

Diagram

(13)

Heart

• slightly to left middle of chest

• size of fist

• composed of cardiac muscle

• contract and relaxes rhythmically/involuntarily

Components of blood

• plasma - dissolves/carries all other components of blood, nutrients, waste

• red blood cells - transport oxygen

• whit blood cells - protect against pathogens

• blood clotting following damage