Transport In Humans(Circulatory System as known as Cardiovascular System)

Blood Vessels

Heart

Coronary Heart Disease

Blood

PLASMA

Dissolved mineral salts,example,hydrogencarbonates,chlorides,sulfates and phosphates of calcium,sodium and potassium.All these occur as ions in the plasma.Calcium is essential for blood clotting.

Food substances,example:glucose,amino acids,fats and vitamins.

Soluble proteins such as fibrinogen , prothrombin and antibodies .Fibrinogen and prothrombin help to fight diseases that involves in blood clotting.They are proteins made in the liver.

Excretory products,for example : urea , uric acid and creatinine.Carbon dioxide is present as hydrogencarbonate ions.

Plasma is about 90% of water and the rest is a complex mixture of various dissolved substances.

Hormones = Insulin

A pale yellowing liquid

RED BLOOD CELLS / ERYTHROCYTES

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It contains the pifment haemoglobin which is a special kind of iron-containing protein.Haemoglobin combinds reversibly with oxygen.This enables red blood cells to transport oxygen from the lungs to all cells in the body.

Mammalian red blood cells has these features:

It is a circular,flattened biconcave disc.The centre of the cell is thinner than its edge.This increases the cell's surface area to volume ratio.The cell can thus absorb and release oxygen at a faster rate.

There are about five millions of red blood cells(erythrocytes) in each cubic millimetre of blood

It does not possess a nucleus,enabling it to carry more haemoglobin and oxygen.

WHITE BLOOD CELLS

BLOOD PLATELETS/THROMBOCYTES

Irregular in shape and contains a nucleus

Have two main kinds of tissue cells : lymphocytes and phagocytes

Keeps the body healthy by fighting diseases

Are larger than red blood cells but are few in number

They contain a nucleus but their normal lifespan in the bloodstream is only a few days

Colourless and does not contain haemoglobin

Can move,change its shape and squeeze the walls of the thinniest blood capillaries into the spaces among tissue cells

It is elastic and can turn bell-shaped in order to squeeze through blood vessels smaller than itself in diameter (less than 0.01mm)

Red blood cells are produced by the bone marrow.The lifespan of red blood cells is about 3-4 months

The Main Vein is the Vena Cava

Two larger lower chambers

The Main Artery is the Aorta.

Two upper chambers

Inferior is also known as posterior

Surrounded by a 'bag' called the pericardium

Superior is known as anterior.

Veins

Capillaries

Arteries

Carry blood away from the heart

need to be able to withstand the immense pressure of the blood

The thick elastic walls help to withstand the high blood pressure in the artery

Have walls which are thick , muscular and elastic

Elasticity enables the artery wall to stretch and recoil or spring back

Microscopic blood vessels that are found between the cells of almost all the tissues

Walls made up of only a single layer of flattened cells called the endothelium

branch repeatedly

Endothelium is partially permeable

have a large surface area for the exchange of substances between the blood and the tissue cells

auricles(part of atria)

Made up with muscle tissue

does not require high pressure

thin muscular walls

Ventricles

Left ventricle requires high pressure

Right ventricle has thinner walls

Have thick muscular walls,especially the left ventricle

Right and left ventricle are separated by a muscular wall called ----

Median Septum

If deoxygenated blood are mixed with oxygenated blood,it will reduce the amount of oxygen being carried to the tissue cells

It prevent the mixing of oxygenated blood and deoxygenated blood

Blood platelets or thrombocytes are not true cells

Play part in the clotting of blood

Causes

PREVENTIVE MEASURES

There are several ways you can help reduce your risk of developing coronary heart disease (CHD), which include the following:

  • Eat a healthy, balanced diet
  • Be more physically active
  • Keep to a healthy weight
  • Give up smoking
  • Reduce alcohol consumption
  • Keep blood pressure under control
  • Keep diabetes under control

Coronary heart disease (CHD) is usually caused by a build-up of fatty deposits (atheroma) on the walls of the arteries around the heart (coronary arteries).

The build-up of atheroma makes the arteries narrower, restricting the flow of blood to the heart muscle. This process is called atherosclerosis.

Your risk of developing atherosclerosis is significantly increased if you:

smoke

have high blood pressure (hypertension)

have a high blood cholesterol level

did not take regular exercise

have diabetes

Other risk factors for developing atherosclerosis include:

being obese or overweight

having a family history of CHD - the risk is increased if you have a male relative under the age of 55, or a female relative under 65, with CHD

a waxy substance called plaque builds up inside the coronary arteries.

These arteries supply oxygen-rich blood to your heart muscle.
When plaque builds up in the arteries, the condition is called atherosclerosis. The buildup of plaque occurs over many years.

Veins carry blood to the heart from all parts of the body

Blood pressure in veins is much lower than the blood pressure

Venules in turn join to form bigger veins

Blood flows more slowly and smoothly in the veins

Thin wall with less elastic tissue

Contain less elastic tissue

Carry deoxygenated blood (except pulmonary vein carries oxgenated blood)

Pulmonary veins brings oxygenated blood back to the heart

Pulmonary artery brings deoxygenated blood away from heart to lungs