The Circulatory System (CIE A Level Biology)

Fig. 1 shows a series of red blood cells passing through a capillary in the tissues. The magnification factor of Fig. 1 is x6000.

Fig. 1

The length of the line marked X in the image shown in Fig. 1 is 4.6 cm.

Calculate the actual diameter of the red blood cell marked X in Fig. 1 Show your working and give your answer in µm to one decimal place.

State and explain one feature of capillaries visible in Fig. 1 that helps them to carry out their function.

Research suggests that in patients with diabetes mellitus red blood cell membranes can harden, reducing the ability of red blood cells to deform and flex.

Suggest and explain the possible symptoms that this could cause in diabetic patients.

Red blood cells and capillaries form part of the circulatory system of some organisms.

Explain why multicellular organisms, such as humans, require a circulatory system while single-celled organisms, such as bacteria, do not.

Fig.1 shows an image of a micrograph of a cross section through a mammalian blood vessel.

Fig. 1

Identify the type of blood vessel shown in Fig.1.

Explain how the blood vessel shown in Fig.1 is adapted to carry out its function.

Fig. 2 shows pressure changes in the blood vessels as the blood passes through different sections of the mammalian circulatory system.

Fig. 2

Explain the need for a separate systemic and pulmonary circulation in mammals. 

Explain the blood pressure in the following sections of Fig. 2

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Scientists collected red blood cell samples from four different mammals; cats, rats, hares and goats. The samples were placed in different concentrations of sodium chloride solution for a set amount of time and the percentage of haemolysed (burst) red blood cells was measured at each sodium chloride concentration. Fig. 1 shows the results of the above experiment.

Fig. 1

The scientists used a colorimeter to measure the percentage of haemolysed red blood cells.

Suggest why a colorimeter could be used to measure this.

Contrast the results for the red blood cells of the goat and the rat.

Explain the results shown for the cat in Fig. 1 at the following sodium chloride concentrations:

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Fig. 2 shows a microscope image of a mammalian blood sample.

Fig. 2

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Fig. 1 represents a capillary as it passes through the tissues of the body along with the surrounding tissue fluid.

Fig. 1

Give three differences between the composition of the blood at the arteriole end of the capillary and the venule end.

Use Fig. 1 to explain the formation of tissue fluid and its return to the capillary.

Protein deficiency in an individual's diet can influence the return of tissue fluid to the capillaries.

Suggest and explain one tissue fluid-related symptom of dietary protein deficiency.

The main component of both blood and tissue fluid is water.

Explain how one property of water makes it an ideal transport medium for organisms with a transport system.

Based on your knowledge of diffusion, explain why multicellular organisms need a specialised transport system.

Fig. 1 shows two organs of the mammalian circulatory system.

Fig. 1

Identify the organs labelled X and Y. 

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Explain the evidence shown in Fig. 1 that determined your answer to part (i).

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Fig. 2 shows a biological drawing of organ X

Fig. 2

Describe the errors contained within this drawing.

The heart, contains two blood vessels that transport blood via the lungs. 

Give the name of these two blood vessels. 

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Explain the movement of blood between the heart and the lungs. Do not include details of the cardiac cycle as part of your answer.

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