A blood cell that uses haemoglobin to bind and transport oxygen.

The fluid of the blood which carries blood cells and other substances.

Large blood vessels with thicker walls which transport blood away from the heart.

Large blood vessel which transports blood towards the heart.

Narrow blood vessel which allows exchange of substances between tissue and blood.

Human blood cells and blood vessels

Combined science

The human circulatory system

The human heart and double circulatory system

Microscopy of human blood cells and blood vessels

Moving into and out of the blood: diffusion, osmosis and active transport

Diffusion and surface area to volume ratio

The importance of exchange surfaces and transport systems in humans

Pupils will learn how the components of the human nervous system enable us to respond to changes outside and inside our bodies.

Pupils learned about biological molecules that are essential to life, including sugars and other carbohydrates, proteins and lipids, and the role of enzymes in catalysing the chemical reactions in which these substances are used and made.

This unit covers the human circulatory system, its link to the gas exchange system, and the adaptations of the heart, blood vessels, and blood components. It explains transport mechanisms like diffusion, osmosis, and active transport, and the need for exchange surfaces in multicellular organisms.

Transport and exchange surfaces in humans

blood vessel that carries blood away from the heart

where exchange of substances between blood and body cells takes place

blood vessel that carries blood towards the heart

Match each word to its correct description.

Which substance in the list is **not** mainly transported in the blood plasma?

Which of the adaptations of a red blood cell increases the rate of diffusion of oxygen? 

Blood vessels are adapted to their function. Which blood vessels are adapted by having thick elastic and muscular walls and narrow lumens?

True or false? The exchange of substances between the blood and body cells only takes place from capillaries.

Some blood vessels contain valves. What is the function of these valves?

Which of these is a waste product in humans?

It acts as a pump pushing blood round the body.

It is made from several different tissues.

Nitrogenous waste produced by cells is transported by the blood to which organ?

In the diagram of the human heart, which letter (A, B, C or D) is the left ventricle?

Starting with the lungs, put these structures in the correct order to describe blood flow through the left side of the heart.

True or false? The pulmonary artery carries oxygenated blood.

Starter Quiz

Which of these is a waste product in humans?