AQA GCSE Biology 8461
Bioenergetics
Cell Biology
Ecology
Homeostasis and Response
Infection and Response
Inheritance, Variation and Evolution
Organisation
Organisation
The pacemaker, the blood vessels and the blood
- 3 things to know
- Paper 1
Overview
The natural and artificial pacemaker, the structure of arteries, veins and capillaries, calculating the rate of blood flow, and blood as a tissue of plasma, red blood cells, white blood cells and platelets, red blood cell adaptations and haemoglobin, telling white from red blood cells, phagocytes, and platelets in clotting.
What you need to know
Answer each one before you reveal it.
Explain why veins contain valves but arteries do not.
How is the rate of blood flow through a vessel calculated?
Questions from this subtopic
Each one with the model answer underneath.
- 1
Where in the heart is the group of cells that sets the natural resting heart rate?
Model answer
In the right atrium.
- 2
What does the heart's natural pacemaker do?
Model answer
It produces electrical impulses that control how often the heart muscle contracts.
- 3
What is an artificial pacemaker used for?
Model answer
It is an electrical device fitted to a patient to correct an irregular heart rate.
- 4
Name the three types of blood vessel found in the body.
Model answer
Arteries, veins and capillaries.
- 5
Describe the structure of an artery and explain how it suits the artery's function.
Model answer
It has thick, muscular and elastic walls with a narrow lumen, which withstand and help maintain the high pressure of blood leaving the heart.
- 6
Explain why veins contain valves but arteries do not.
Model answer
Blood in the veins is at low pressure and could flow backwards, so valves are needed to keep it moving towards the heart.
Other ways to work this
The same content, four other ways.
What is inside Levo
Six ways to work the same material.
Every question in Organisation, on a schedule.
Attempt a question from memory, write the correct version, then attempt it again. Levo records the jump between your first attempt and your last, and brings each question back on the day you are due to forget it.
Or £46 a year, about £3.83 a month. Cancel anytime.