1. The Circulatory System
The circulatory system is also known as the cardiovascular system. It consists of…
1. Blood
2. Blood Vessels
3. The Heart
The three main types of blood vessels
are arteries, veins and capillaries.

2. The Circulatory System and Transport
All the cells of the body require energy in order to work properly, e.g. muscle cells would not be able to contract without a supply of oxygen and glucose.
The circulatory system is therefore the body’s ‘transport system’. It carries…

3. The Circulatory System and Transport
All the cells of the body require energy in order to work properly, e.g. muscle cells would not be able to contract without a supply of oxygen and glucose.
The circulatory system is therefore the body’s ‘transport system’. It carries…
Blood from the heart to all the cells of the body, providing them with glucose and oxygen.
Waste products away from the cells of the body, including carbon dioxide and urea.
It is a delivery service…
…and a waste disposal unit!

5. How Blood Is Pumped Around the Body
Blood flows around the body in a double circulatory system.
(A)
(V)
Heart
Body
Lungs
Blood always travels away from the heart through the arteries (A).
Blood always returns to the heart through the veins (V)
The heart is a DOUBLE pump.
There two major, separate ‘loops’ to the circulatory system:
The pulmonary circuit – carries blood from the heart to the lungs and from the lungs back to the heart.
The systemic circuit – carries blood from the heart to the head and body and back to the heart.

6. Pulse Rates
Pulse rates are caused by the action of the heart as it pumps blood around the body.
Every time the heart beats (contracts) it can be felt as a pulse, due to the pumped blood making the artery walls expand and then contract.
It can be measured wherever an artery passes close to the surface of the body.

7. Pulse Rates The four main pulse rate points of the body are…
Temporal Pulse Found just over the temple on either side of the forehead.
Carotid Pulse Found on either side of the neck to the side of the windpipe.
Radial Pulse Found at the base of the thumb on the inside of each wrist.
Femoral Pulse Found at the top of each leg in the groin.

8. The Major Blood Vessels
Arteries
Veins

9. The Circulatory System - Major Blood Vessels
Pulmonary artery (to lungs)
Aorta (main artery)
Right atrium
Right ventricle
Pulmonary vein (from lungs)
Vena cava (main vein)
Lungs
Hepatic artery (to liver)
Hepatic vein (from liver)
Gut
Hepatic portal vein (from gut to liver)
Renal artery (to kidneys)
Renal vein (from kidney)
Kidney

10. Blood Vessels Arteries Veins Capillaries
Non-elastic fibres
Arteries carry blood away from the heart and have a thick, elastic, muscular wall.
Non-elastic fibres
Lumen
Muscle + elastic fibres
Muscle + elastic fibres
Veins carry blood towards the heart and have a thin elastic and muscular wall. Veins have VALVES to prevent blood going backwards.
Non-elastic fibres
Lumen
Muscle + elastic fibres
Capillary walls are one cell thick. Exchange of nutrients, waste and gases happens here..