Biology Practice TestGrade 9………………………………………………………………………………………………………………………………Answer ALL the questions. Write your answers in the spaces provided.

1 . Cholesterol is a molecule that is needed by the human body. Unfortunately, too much cholesterol in the body can be harmful. The graph shows the relationship between the level of cholesterol in the blood and the number of deaths from heart disease. The data refer to men aged 44 to 60 in the UK.

(a) (i) How many deaths occur each year from heart disease in men who have the highest blood cholesterol level recorded in these data? ................................................................................................................................

(1) (ii) How many fewer deaths would occur each year from heart disease if these men reduced their blood cholesterol to 4mmolperlitre? ................................................................................................................................(1)

(b) Cholesterol causes heart disease by blocking blood vessels leading to important organs such as the heart. (i) Name the blood vessel that transports blood to the heart muscle. ................................................................................................................................(1) (ii) Explain how blocking this blood vessel can cause death. ................................................................................................................................ ................................................................................................................................ ................................................................................................................................ ................................................................................................................................ ................................................................................................................................ ................................................................................................................................(3)

(c) Cholesterol is used in the human body to make some important substances. Three of these substances are shown in the table. Complete the table by giving one function of each substance.

(9marks)

2 . A teacher was helping to prepare an athlete for a marathon. The teacher measured the heart rate of the athlete every ten minutes during a training session lasting one hour. The results are shown in the table.

(a) Describe the pattern shown by the results. .................................................................................................................................... .................................................................................................................................... .................................................................................................................................... (2)(b) Name the hormone responsible for the change in heart rate during exercise. ....................................................................................................................................(1)(c) How would you expect the results to be different in someone who smokes? Give a reason for your answer. .................................................................................................................................... .................................................................................................................................... .................................................................................................................................... ....................................................................................................................................(2)

(d) Name one system in the body, other than the circulatory system, that is affected by smoking. ....................................................................................................................................(1)(Total 6 marks)

3 . John ate some rice. The rice contained starch. Describe how the starch is broken down in the digestive system. .................................................................................................................................... .................................................................................................................................... .................................................................................................................................... .................................................................................................................................... .................................................................................................................................... .................................................................................................................................... .................................................................................................................................... .................................................................................................................................... .................................................................................................................................... .................................................................................................................................... .................................................................................................................................... .................................................................................................................................... ....................................................................................................................................(Total 6 marks)

4 . People with diabetes may not produce enough insulin and so are unable to control their blood glucose level. To overcome this, they inject themselves with insulin in the leg.

The passage below describes how the injected insulin travels from the leg to the liver. Use suitable words to complete the sentences in the passage.The insulin travels to the heart in a blood vessel called the ……………………………, the largest vein in the body. Blood enters a chamber called the right ……………………………., and passes to the right ventricle before being pumped in the pulmonary artery to the ……………………………. . Backflow of blood is prevented by atrio-ventricular and semilunar ……………………………. . The blood containing insulin returns to the heart in the pulmonary vein. It then leaves the heart in the ……………………………., the largest artery in the body. Finally, the insulin is taken into the liver by the ……………………………. artery. When insulin reaches the liver cells it causes the conversion of ……………………………. into an insoluble carbohydrate called ……………………………. .(Total 8 marks)

5 . The diagrams show three neurones (nerve cells).

(a) (i) Name the parts labelled X and Y on neurone C. X ............................................................................................................................ Y ............................................................................................................................(2) (ii) Which neurone passes impulses from a receptor to the central nervous system? ................................................................................................................................(1)

(iii) Which neurone is found only in the central nervous system? ................................................................................................................................(1)(b) The table shows the speed of a nerve impulse along neurones with different diameters, measured in micrometres (µm).

(i) Plot a line graph of the data in the table on the grid below.

(2)

(ii) Describe the relationship between the diameter of a neurone and the speed of an impulse along the neurone. ............................................................................................................................... ...............................................................................................................................(1)(iii) Suggest how fast an impulse would travel along a neurone with a diameter of 5µm. .......................................................................................................... m per second(1)(Total 8 marks)

6 . Ultrafiltration and selective reabsorption are processes that take place in the kidneys. (a) Give three ways in which ultrafiltration differs from selective reabsorption.

1............................................................................................................................. ............................................................................................................................... ...............................................................................................................................

2............................................................................................................................. ............................................................................................................................... ...............................................................................................................................

3............................................................................................................................. ............................................................................................................................... ...............................................................................................................................(3)

(b) Kidneys can produce urine that varies in volume and concentration depending on certain events. (i) Complete the table by writing the correct word in each box to show the description of urine after each event. Some boxes have been completed for you.

(4)(ii) Damage to the pituitary gland can prevent the secretion of the hormone ADH. Explain how this affects osmoregulation by the kidney.

............................................................................................................................ ............................................................................................................................... ............................................................................................................................... ............................................................................................................................... ............................................................................................................................... ............................................................................................................................... ............................................................................................................................... ............................................................................................................................... (4)(11marks)

7 . (a) Substances move into and out of cells by different methods.

Three methods, A, B and C, are described below. A movement of substances against a concentration gradient B movement of water from a dilute solution to a more concentrated solution through a partially permeable membrane C movement of substances down a concentration gradient Complete the table by putting the correct letter for each method.

(3) (b) Complete the sentences below by writing a correct word or phrase in the blank spaces. (i) An example of diffusion in the lung of a mammal involves a substance called oxygen, which moves from the ................................................ to the .................................................(2) (ii) An example of osmosis in the kidney of a mammal involves a substance called ................................................, which moves from the nephron to the .................................................(2) (iii) An example of active transport in a flowering plant involves uptake of amineral salt, which moves from the ................................................ to the ................................................ in a root hair cell.(2)

(c) The graphs show the effect of changing the temperature on the rate of movement of substances into cells.

(i) Which graph shows the effect of temperature on diffusion? ...............................................................................................................................(1)(ii) Which graph shows the effect of temperature on active transport? ...............................................................................................................................(1)(Total 11 marks)

8 . The diagram shows a section of the human eye.

(a) Name the part labelled A. ...............................................................................................................................(2) (b) Some people have a rare genetic condition that makes the cornea become cloudy. As a result they find it difficult to see clearly and may become blind. (i) Suggest why a cloudy cornea makes it difficult for a person to see clearly. ............................................................................................................................... ............................................................................................................................... ............................................................................................................................... ...............................................................................................................................(3)(5marks)

8 . Some large molecules are made from smaller basic units.

(a) The table shows some important large molecules in living organisms. Complete the table to show the missing large molecule and the smaller basic units.

(b) Protein is broken down into its smaller units by a protease enzyme. The graph shows how the activity of a protease is affected by temperature.

Describe how the rate of reaction of this protease varies with temperature. ............................................................................................................................... ............................................................................................................................... ............................................................................................................................... ...............................................................................................................................(2)(Total 5 marks)9 . The diagram shows part of the human digestive system.

(a) On the diagram, use an arrow and the letter L to show the large intestine.(1) (b) On the diagram, use an arrow and the letter B to show where bile is made.(1) (c) Give two functions of bile. 1............................................................................................................................. ............................................................................................................................... ............................................................................................................................... 2............................................................................................................................. ............................................................................................................................... ...............................................................................................................................(2)

(d) The products of digestion are absorbed by villi in the small intestine. Explain how the structure of villi helps absorption of these products. ............................................................................................................................... ...............................................................................................................................

.............................................................................................................................. ...............................................................................................................................(2)(Total 6 marks)

10. The diagram shows a nephron from a human kidney.

(a) (i) Name the parts of the nephron labelled A, B and C. A ............................................................................................................................. B ............................................................................................................................. C ............................................................................................................................(5) (ii) Ultrafiltration occurs between the glomerulus and part A. Explain what is meant by the term ultrafiltration. ............................................................................................................................... ...............................................................................................................................

............................................................................................................................... ...............................................................................................................................3)

(b) The table shows the concentrations of urea in part A and in part C.

(i) How many times more concentrated is the urea in part C compared withpart A? ............................................................................................................................... ...............................................................................................................................(1) (ii) Suggest why the concentration of urea is greater in part C than in part A. ............................................................................................................................... ...............................................................................................................................(1)(Total 10 marks)…………………………………………………………………………………………………………………………

TOTAL FOR PAPER: 85 MARKS

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