The Heart, Blood Vessels and Cardiac Cycle
How the heart moves blood around the body: the four chambers, the three types of blood vessel and their jobs, and the cardiac cycle of filling and pumping.
Justify the choices, the way you are assessed
Free interactive practice on the decisions the assessment actually asks you to justify.
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The heart
The heart is a muscular pump that moves blood around the body. It has four chambers: two atria at the top that receive blood, and two ventricles at the bottom that pump it out. Blood travels in three types of vessel, and the cardiac cycle describes how the heart fills and pumps.
Words for the heart
Learn these four terms before you follow the blood around the body.
Three blood vessels
Each type of blood vessel has a structure that suits its job.
Structure to function, every time
To reach the top grades, link each structure to its function, such as thick artery walls to withstand high pressure and one-cell-thick capillary walls for a short diffusion distance. You do not need to name the heart valves.
Match the part to its job
- an artery
- a vein
- a capillary
- an atrium
- carries blood away from the heart at high pressure
- carries blood back to the heart and has valves
- allows the exchange of oxygen and carbon dioxide
- a top chamber that receives blood into the heart
Match the term to its meaning
- ventricle
- vasoconstriction
- vasodilation
- cardiac cycle
- a bottom chamber that pumps blood out
- when blood vessels narrow
- when blood vessels widen
- one full sequence of the heart filling and pumping
Which carries blood away?
Which blood vessel carries blood away from the heart?
- The artery.
- The vein.
- The capillary.
- The venule.
Features of an artery
Select the TWO features of an artery.
- Thick muscular walls.
- It carries blood at high pressure.
- It has valves to stop backflow.
- Its walls are one cell thick.
Follow the blood
Put the path of the blood in order, starting as it returns to the heart.
- Deoxygenated blood enters the right atrium
- The right ventricle pumps it to the lungs
- Oxygenated blood returns to the left atrium
- The left ventricle pumps it around the body
Summarise the heart
The heart has four chambers. The top chambers are the _____ and the bottom chambers are the _____. An _____ carries blood away from the heart at high pressure, while a _____ carries it back and has valves. The heart filling with blood is called _____.
Count the chambers
How many chambers does the human heart have?
Spot the two artery features
Tap the TWO features of an artery.
- thick muscular walls
- carries blood at high pressure
- has valves
- walls one cell thick
- carries blood to the heart
Which blood vessel?
Decide which blood vessel each description fits.
- It has thick muscular walls and carries blood at high pressure
- It has valves and carries blood back to the heart
- Its walls are one cell thick for the exchange of gases
Explain the artery
Explain how the structure of an artery suits its function. Describe its walls and the pressure of the blood it carries, and link each feature to its job.
- Describe the walls of an artery
- Describe the blood pressure in an artery
- Link each feature to its function