CIRCULATORY SYSTEM

THE STRUCTURE OF HEART

PARTS OF THE HEARTCHAMBERS OF THE HEART:- RIGHT ATRIUM- receives deoxygenated blood from the body. RIGHT VENTRICLE- receives deoxygenated blood from right

atrium LEFT ATRIUM- receives oxygenated blood from the lungs LEFT VENTRICLE- receives oxygenated blood from the left

ventricleBLOOD VESSELS ASSOCIATED WITH THE HEART:- INFERIOR AND SUPERIOR VENA CAVA- carries deoxygenated

blood from the body to the right atrium of the heart PULMONERY ARTERY- carries deoxygenated blood from the

right ventricle to the lungs PULMONERY VEIN- carries oxygenated blood from the lungs to

left atrium of the heart. AORTA- carries oxygenated blood form the left atrium of the

heart to all body parts VALVES:- prevents the back flow of blood.

BLOOD CIRCULATION During one complete circulation of the human (mammalian) body, blood travels twice through the heart.

Blood circulates through two systems :-

Pulmonary circulation; which pumps blood to and from the lungs.

Systematic circulation; which pumps blood to and from different parts of the body.

PULMONARY CIRCULATION

Deoxygenated blood from different parts of the body is collected through 2 main veins; superior & inferior vena cava.

They empty the blood into the right atrium.

PULMONARY CIRCULATION

From the right atrium, blood is pumped to right ventricle

This deoxygenated blood from right ventricle is pumped to the lungs through the pulmonary artery to the capillaries in the lungs where it absorbs more O2 and is called oxygenated blood.

O2

in2CO2

out

PULMONARY CIRCULATION

This oxygenated blood returns from the lungs through the pulmonary veins, which empty the content into the left atrium.

SYSTEMIC CIRCULATION When left atrium is full, it contracts forcing blood into the left ventricle and then left ventricle contracts forcing blood into aorta.

From the left ventricle, the blood is pumped to different parts of the body through aorta.

When deoxygenated blood returns through the main veins (inferior and superior vena cava) to the right atrium, the double circulation is complete.

SYSTEMIC CIRCULATION

When deoxygenated blood returns through the main veins (inferior and superior vena cava) to the right atrium, the double circulation is complete

SVC

IVC

Right Atrium

Right Ventricl

e

Pulmonary artery

lungs

Pulmonary vein

Left atrium

Left ventricl

e

Aorta

Body Organs