Explain how the human circulatory system is adapted to provide oxygen and remove waste products from our tissues.

Blood is an important body fluid in the circulatory system of humans and other vertebrates.

What are the main components of the blood?

Name each component and describe its function in the human body.

As the heart beats, it pumps blood through a system of blood vessels.

The picture shows cross sections of the three types of blood vessels present in the human body.

Which blood vessel in the picture above is a capillary? Explain your answer.

Veins need to carry the blood upwards against gravity when we are standing.

How does their structure differ from that of arteries to facilitate this function?

Predict the differences between blood collected from an artery and blood collected from a vein.

The picture shows a diagram of a human heart.

Label the different parts of the human heart.

Provide a detailed account of the path of blood starting in the vena cava, through the heart, lungs and back to the body, finishing your account back in the vena cava.

Make sure you name each vessel, chamber and valve.

Leukaemia is a type of cancer characterised by the abnormal production and accumulation of cancerous white blood cells in the bone marrow.

The cancer cells overcrowd the bone marrow, impairing its ability to produce blood components.

Symptoms of leukaemia include:

• Fatigue (tiredness that lasts a long time and doesn't improve with rest).
• Bruising and bleeding more easily, or bleeding that takes longer to stop.
• Infections that are more frequent, severe, or prolonged.

Suggest why patients with leukaemia experience these symptoms.

The circulatory system transports oxygen and nutrients to cells and takes away their waste products. 

What type of circulatory system do humans have?

Amphibians have a three-chambered heart that has two atria and only one ventricle rather than the four-chambered heart of mammals.

Suggest why the circulatory system of amphibians is less efficient than that of mammals.