CIRCULATORY SYSTEM. English

CIRCULATORY SYSTEM

C.E.I.P. Santa Ana (Madridejos)

1.- CIRCULATORY SYSTEM: The circulatory system is formed by the blood vessels and the heart.

It transports nutrients, oxygen, and residues around the body in the blood.

1.1.- Blood vessels: The blood vessels are the conducts that transport blood throughout the body. There are three types of blood vessels: .- The arteries: which carry the blood away from the heart to the organs. .- The veins: which carry blood from the organs back toward the heart. .- The capillaries: are the smallest blood vessels, connect veins and arteries, and enable the exchange of water, oxygen and carbon dioxide between blood and every cell in the body[3]

CIRCULATORY SYSTEM

C.E.I.P. Santa Ana (Madridejos)

1.2.- Heart: The heart is a muscular organ, that is responsible for pumping blood through the blood vessels. The average human heart, beating at 72 beats per minute.

It’s divided into two unconnected parts: right side (for blood with carbon dioxide) and left side (with oxygenated blood).

Each part is divided in two linked by a valve: The atrium: the upper part, and the ventricle: the lower part.

1.3.- Blood: It’s a red liquid, composed of cells suspended in a watery liquid called plasma.

Plasma is yellow liquid in our blood. 90% of plasma is water. The rest are dissolved substances which include nutrients. Main functions of plasma are to transport nutrients to the cells in the body and to remove waste products from them.

Red blood cell (erythrocytes) transport oxygen from the lungs to all parts of the body. They contain a red pigment called haemoglobin. They also carry carbon dioxide from our body cells to our lungs.

White blood cells destroy germs and protect us against infections.

Platelets: block wounds in order not to lose too much blood.

CIRCULATORY SYSTEM

C.E.I.P. Santa Ana (Madridejos)

2.- THE BLOOD CIRCULATION:

The transport system in human is called circulatory system. The human circulatory system is a called double circulatory system because the blood flows through the heart twice in a complete circuit. The human double circulatory system consists of the pulmonary circulation which transports blood between the heart and the lungs and the systemic circulation which transports blood between the heart and all other parts of the body.

We can say that is complete because the arterial blood is separated from the vein blood.

SUMMARY: A circulatory system has three basic components: 1.- Blood vessels are a complex network of blood vessel carries materials to the tissue and back to the heart. There are three main types of blood vessels; arteries, veins and capillaries.

2.- Pumping organ is the heart; blood is moved through the body by muscular contractions of the heart.

3.- The circulating fluid is called blood which transports useful and waste materials.

CIRCULATORY SYSTEM

C.E.I.P. Santa Ana (Madridejos)

Valves are present in some blood vessels (veins) to prevent backflow and ensure that bloods flows in one direction only. There valves in the heart too.

CIRCULATORY SYSTEM:

GLOSARY-VOCABULARY:

Blood: sangre

blood vessels: vasos sanguíneos

artery: arteria

Veins: venas

capillaries: capilares

heart: corazón

To pump: bombear

atrium: aurícula

ventricle: ventrículo

Valves: válvulas

nutrients: nutrientes

Platelets: plaquetas

waste products: productos de desecho

Red blood cells: glóbulos rojos

pulmonary circulation: circulación pulmonar WRITE YOUR OWN WORDS:

White blood cells: glóbulos blancos.

systemic circulation: circulación general.