EduNinja• Describe the circulatory system as a system of blood vessels with a pump and valves to ensure one-way flow of blood
Fig. 1.1 is a diagram of the human heart. The diagram shows the phase during the heart beat when the atria contract. The blood vessels that carry blood to and from the heart are labelled A to F.
Fig. 1.1
State the function of valves 1 and 2 in the heart.
Fig. 2.1 shows a cross-section of a human heart.
Fig. 2.1
Complete the sentence about blood vessel C.
Blood vessel C transports blood from the to the
。
What ensures that blood flows in one direction in the human circulatory system?
diffusion of carbon dioxide
diffusion of oxygen
thick walled arteries
valves
In a mammal, what ensures the blood flows one-way round the circulatory system?
brain
capillaries
lungs
valves
Which statements describe how the structures in the circulatory system function?
1 a muscular pump to push blood into vessels
2 valves to ensure one-way blood flow
3 veins to take blood away from the heart
4 vessels to return blood to the heart
1, 2 and 3
1, 2 and 4
1, 3 and 4
2, 3 and 4
The diagram shows a garden pond with a fountain worked by a pump. The fountain brings oxygen from the air to fish in the pond.
The system can be compared with part of the human circulatory system. The pump is compared with the heart.
What are P and Q compared with?
P
Q
aorta
pulmonary artery
pulmonary artery
vena cava
pulmonary vein
vena cava
vena cava
aorta
Where are valves found that prevent blood from flowing in the wrong direction?
capillaries and arteries
lungs and veins
heart and capillaries
heart and veins
How does blood enter the heart?
through arteries into the atria
through arteries into the ventricles
through veins into the atria
through veins into the ventricles