THE TRANSPORT SYSTEM

By: Virginia Posada & Ana Maria Racines

DEFINITIONS

Artery: are blood vessels that carry blood away from the heart. (Most carry oxygenated blood).

Vein: are blood vessels that carry blood towards the heart. (Most veins carry deoxygenated blood.)

Heart Valve: it normally allows blood flow in one direction through the heart. There are four valves in the mammalian heart.

JOB OF THE CIRCULATORY SYSTEM

Transport materials throughout the body. It transports nutrients, water, and oxygen to your body cells and carries away wastes such as carbon dioxide that body cells produce.

HEART

The heart is located in the center of your chest slightly to the left. It's job is to pump your blood and keep the blood moving throughout your body.

DIAGRAM OF THE HEART

CORONARY ARTERIES The coronary arteries deliver blood to the heart muscle,

providing a continuous supply of oxygen and nutrients needed for it to stay healthy and function normally.

Blood is supplied to the heart by its own vascular system, called coronary circulation.

Your left ventricle pumps blood into the main artery of your body, called the aorta. Close to the heart, the two main coronary arteries branch off of your aorta.

The left main coronary artery is a short vessel that branches into the:› Left anterior descending artery, which supplies blood to the

front (anterior wall) and part of the side (anterolateral wall) of the left ventricle, to the top of the left ventricle, and to most of the wall between the ventricles (interventricular septum).

› Circumflex artery, which passes behind the heart between the left atrium and left ventricle and supplies blood to the side (lateral wall) of the left ventricle. In a small number of people, the circumflex artery supplies the lower and back portions of the left ventricle.

The right coronary artery supplies blood to the right ventricle and then supplies the underside (inferior wall) and backside (posterior wall) of the left ventricle.

ACTIONS OF THE HEART

Atria collect blood from veins. Atria contractatrioventricular valves open. Blood is pumped into ventricles. Ventricle contracts, atrioventricular valves close

and semilunar valves open. Blood is pumped into arteries, semilunar valves

close. Cycle repeats. http://www.youtube.com/watch?v=JA0Wb3gc4mE&NR=1

THE CONTROL OF THE HEART BEAT

The heart muscle tissue can contract on its own , it is called myogenic muscle contraction.

Region responsible for initiating each contraction: pacemaker.

THE BLOOD

Blood is composed of plasma, erythrocytes (red blood cells), leukocytes)white blood cells and platelets.

FUNCTIONS OF BLOOD

Blood carries oxygen and many other substances around your body.

Its functions is to transport and defence against disease.

VEINS AND VENULES CAPILLARIES ARTERIES AND ARTERIOLES

Function is to carry blood from tissues to the heart

Function is to allow exchange of materials between the blood and the tissues

Function is to carry blood from the heart to the tissues

Thin walls, mainly collagen, since blood at low pressure Very thin, permeable walls, only one cell thick to

allow exchange of materialsThick walls with smooth elastic layers to resist high

pressure and muscle layer to aid pumping

Large lumen to reduce resistance to flow. Very small lumen. Blood cells must distort to pass through. Small lumen

Many valves to prevent back-flow No valves No valves (except in heart)

Blood at low pressure Blood pressure falls in capillaries. Blood at high pressure

Blood usually deoxygenated (except in pulmonary vein)

Blood changes from oxygenated to deoxygenated (except in lungs)

Blood usually oxygenated (except in pulmonary artery)

SUBSTANCES THAT THE BLOOD TRANSPORTS

SUBSTANCE WHERE REASON

Oxygen Red blood cells Transported from lungs to all cells for respiration

Carbon dioxide Plasma Transported from all cells to lungs for excretion

Nutrients (e.g. glucose, amino acids, vitamins,

lipids, nucleotides)Plasma Transported from small intestine to liver and from

liver to all cells

Waste products (e.g. urea, lactic acid) Plasma Transported from cells to liver and from liver to

kidneys for excretion

SUBSTANCE WHERE REASON

Hormones Plasma Transported from glands to target organs

Proteins (eg albumins) Plasma Amino acid reserve

Blood clotting factors Plasma At least 13 different substances (mainly proteins) required to make blood clot.

Antigens and antibodies Plasma Part of immune system

Water Plasma Transported from large intestine and cells to kidneys for excretion.

Bacteria and viruses plasma

Heat Plasma Transported from muscles to skin for heat exchange.

BIBLIOGRAPHY

Human Body and Mind , BBC URL: http://www.bbc.co.uk/science/humanbody/body/factfiles/heart/heart.shtml

Human heart structure , URL:http://www.tutorvista.com/content/biology/biology-ii/transportation/heart.php

QUIZ

1.)How many chambers does the heart have ?

A.Six B.Five C.Four D.Three

2.)The movement of blood trough the heart and body is called:

A.Circulation B.Locomotion C. Ventriculation D.Heart Pump

3.)The beating sound from your heart comes from:

A.Blood going in wrong direction B.Valves in your heart closing C.The heart skipping beats D.Pacemaker

4.)The atria are the ´´upstairs´´ chambers of your heart and these parts are the ´´downstairs´´ of your heart

A.Valves B.Ventricles C.Blood D.Pulmonary arteries

5.)What wall separates the right and left side of the heart

A.Ventricle B.Atrium C.Septum D.The great wall

6.)The tubes that carry blood back to the heart :

A.Arteries B.Veins C.Pipes D.Tubas

7.)What is the main function of the circulatory system?

A.Carries inside carbon dioxide B.Help us breathe C.To supply blood to the body D.Control the blood flow around the body

8.)The blood leaving the aorta

A.Red blood cells B.Carbon dioxide C. Oxygen D.White blood cells