Which vessels carry blood away from the heart?

arteries. Arteries always carry blood away from the heart.

Which vessels have valves?

veins. Valves keep low-pressure blood moving towards the heart.

How thick is a capillary wall?

one cell. This allows quick exchange with the tissues.

Which vessel carries deoxygenated blood from the heart to the lungs?

pulmonary artery. It is the only artery carrying deoxygenated blood.

Why do arteries have thick, elastic walls?

to withstand high pressure. Blood leaves the heart in strong surges.

Blood vessels · Cambridge IGCSE Combined Science revision

In plain words

Blood leaves the heart in thick-walled arteries under high pressure, spreads out through tiny, thin capillaries where the swapping of substances happens, and drifts back in wide veins under low pressure. Each kind is built for its job.

Three things to know

Arteries carry blood away from the heart at high pressure. They have thick, muscular, elastic walls and a narrow space inside (lumen).
Veins carry blood back to the heart at low pressure. They have thinner walls, a wide lumen, and valves to stop the blood flowing backwards.
Capillaries are tiny, with walls one cell thick, so substances can pass easily between the blood and the cells.

Tips and tricks

Arteries carry blood Away from the heart: A for artery, A for away.
The pulmonary artery is the odd one out: it carries deoxygenated blood. Arteries are defined by direction, not by oxygen.

5 questions, about 2 minutes.

It lands in your notebook with its questions as flashcards.

Blood vessels: 5 questions and answers

These are the quiz’s questions. Do the quiz first, then come back here for the ones that got you.

Which vessels carry blood away from the heart?
- arteries (the answer)
- veins
- capillaries
- venules
Arteries always carry blood away from the heart.
Which vessels have valves?
- arteries
- veins (the answer)
- capillaries
- all of them
Valves keep low-pressure blood moving towards the heart.
How thick is a capillary wall?
- one cell (the answer)
- ten cells
- as thick as an artery's
- it has no wall
This allows quick exchange with the tissues.
Which vessel carries deoxygenated blood from the heart to the lungs?
- aorta
- pulmonary vein
- pulmonary artery (the answer)
- vena cava
It is the only artery carrying deoxygenated blood.
Why do arteries have thick, elastic walls?
- to store blood
- to withstand high pressure (the answer)
- to let substances through
- to keep blood warm
Blood leaves the heart in strong surges.

5 questions

Tap an answer and you’ll see straight away whether it’s right, and why.

Worksheet

3 questions, 7 marks. Write your answers on paper, then check them.

Blood vessels

Cambridge IGCSE Combined Science 0653 · 7 marks · papermunch.org

Name ______________________________ Date ______________

Describe how the structure of an artery is related to its function.[3]
Show answerHide answer
It has a thick wall with muscle and elastic tissue, and a narrow lumen, so it can withstand and keep up the high pressure of blood coming from the heart.
I got this one
Explain why veins have valves.[2]
Show answerHide answer
The blood in veins is at low pressure, so valves are needed to stop it flowing backwards.
I got this one
Explain how capillaries are adapted for the exchange of substances.[2]
Show answerHide answer
Their walls are one cell thick, giving a short diffusion distance, and there are so many of them that every cell is close to one.
I got this one

Answers: Blood vessels

1. It has a thick wall with muscle and elastic tissue, and a narrow lumen, so it can withstand and keep up the high pressure of blood coming from the heart.
2. The blood in veins is at low pressure, so valves are needed to stop it flowing backwards.
3. Their walls are one cell thick, giving a short diffusion distance, and there are so many of them that every cell is close to one.