INTERNATIONAL ADVANCED LEVEL Biology Topic 1 Molecules, Transport and Health EXAM QUESTIONS BOOKLET alevelbiology.co.uk 1. Use this booklet to revise for exams and improve exam technique. Ensure you identify areas of strength and weakness near exam time to make your revision effective, and use the revision notes to fill in any gaps. alevelbiology.co.uk 1. The figure below represents a water molecule. Water molecules are polar. As a result, they attract each other and other polar molecules. Draw the process of solution of NaCl in water. Your drawing should show: ▪ The bond(s) between the two molecules ▪ The name of the bond ▪ The mechanism of solution of NaCl into water [Total 3 marks] 2. Water is important in many biological reactions. Complete the table below by writing an appropriate term next to each description. [Total 2 marks] alevelbiology.co.uk 3. Ponds provide a very stable environment for aquatic organisms. Three properties of water that contribute to this stability are as follows: ▪ The density of water decreases as the temperature falls below 4°C, so ice floats on the top of the pond. ▪ It acts as a solvent for ions such as nitrates (NO3–). ▪ A large quantity of energy is required to raise the temperature of water by 1°C. Explain how these three properties help organisms survive in the pond. In your answer you should make clear the links between the behaviour of the water molecules and the survival of the organisms. ..................................................................................................................................... ..................................................................................................................................... ..................................................................................................................................... ..................................................................................................................................... ..................................................................................................................................... ..................................................................................................................................... ..................................................................................................................................... ..................................................................................................................................... ..................................................................................................................................... ..................................................................................................................................... ..................................................................................................................................... ..................................................................................................................................... ..................................................................................................................................... ..................................................................................................................................... ..................................................................................................................................... ..................................................................................................................................... ..................................................................................................................................... ..................................................................................................................................... ..................................................................................................................................... ..................................................................................................................................... ..................................................................................................................................... ..................................................................................................................................... ..................................................................................................................................... [Total 8 marks] alevelbiology.co.uk 4. Read through the following account of the properties of water, then write on the dotted lines the most appropriate word or words to complete the account. Water has the chemical formula ………………………………… . Water molecules are described as …………………………………. because they have a slight positive charge at one end of the molecule and a slight negative charge at the other end. As a result, individual molecules form …………………………………. bonds with each other. Water is an important …………………………………. in living organisms because most biochemical reactions take place in aqueous solution. Water also has a high …………………………………., which means that its temperature remains relatively stable despite large changes in the temperature of the surrounding environment. (Total 5 marks) 5. Read through the following account of compounds used for energy storage in cells, then write on the dotted lines the most appropriate word or words to complete the account. Water is the universal …………………………. in living organisms. Molecules which dissolve easily in water can produce osmotic effects. A high concentration of small, soluble molecules within a cell can cause water .......................…………. the cell. This effect is reduced if the molecules used for storage in a cell are ……………………………. . Therefore, energy storage compounds are usually either polysaccharides or …………………………….. . Examples of storage polysaccharides include starch and ……………………………. . Starch is found mainly in ……………………………. cells. (Total 6 marks) alevelbiology.co.uk 6. The table below refers to the formula and structure of two biological molecules. Complete the table by filling in the name, the formula or the structure of the molecule where appropriate in the empty boxes. Name Formula Structure Amylose (Total 4 marks) 7. The statements in the table below refer to three polysaccharide molecules. If the statement is correct, place a tick (✓) in the appropriate box and if the statement is incorrect, place a cross (x) in the appropriate box. (Total 4 marks) alevelbiology.co.uk 7. The diagram below is an electron micrograph of part of a cell from a human liver. This cell is responsible for converting glucose in the body into glycogen for storage. The glycogen can be seen as granules in the cytoplasm. (i) Describe the molecular structure of glycogen. ..................................................................................................................................... ..................................................................................................................................... ..................................................................................................................................... ..................................................................................................................................... ..................................................................................................................................... ..................................................................................................................................... ..................................................................................................................................... ..................................................................................................................................... [4] (ii) Name the type of chemical reaction that takes place during the formation of glycogen. ..................................................................................................................................... [1] [Total 5 marks] alevelbiology.co.uk 9. The table below shows features of arteries, veins and capillaries. If the statement is correct, place a tick (✓) in the appropriate box, and if the statement is incorrect place a cross (x) in the appropriate box. Feature Arteries Veins Capillaries Walls permeable Collagen fibres present in walls Endothelium present Series of valves present (Total 4 marks) 10. The diagram below shows a section of a human heart at a specific stage in the cardiac cycle. (a) Name the stage of the cardiac cycle shown in the diagram and give two reasons for your choice. Stage ..................................................................................................................................... Reason 1...................................................................................................................... ..................................................................................................................................... Reason 2...................................................................................................................... ..................................................................................................................................... (3) alevelbiology.co.uk 11. (a) Cardiac muscle contracts myogenically. Explain what is meant by the term myogenic. ..................................................................................................................................... ..................................................................................................................................... ..................................................................................................................................... (2) (b) Explain what is meant by a double circulatory system. ..................................................................................................................................... ..................................................................................................................................... ..................................................................................................................................... . [2] (Total 4 marks) 12. Explain what is meant by each of the following terms. (a) The cardiac cycle ..................................................................................................................................... ..................................................................................................................................... ..................................................................................................................................... ..................................................................................................................................... ..................................................................................................................................... ..................................................................................................................................... (3) (b) Coronary circulation ..................................................................................................................................... ..................................................................................................................................... ..................................................................................................................................... ..................................................................................................................................... ..................................................................................................................................... ..................................................................................................................................... (3) (Total 6alevelbiology.co.uk marks) 13. The diagram shows a section through a human heart. (a) Which of the blood vessels labelled A to D (i) Takes blood from the heart to the muscles of the arms and legs; ..................................................................................................................................... (1) (ii) Is a vein which contains oxygenated blood? ..................................................................................................................................... (1) (b) Is the right ventricle filling with blood or emptying? Give two pieces of evidence from the diagram to support your answer. Filling or emptying? .................................................................................................. Evidence 1................................................................................................................................... ..................................................................................................................................... 2................................................................................................................................... ..................................................................................................................................... (2) (Total 4 marks) alevelbiology.co.uk 14. The oligochaete subclass Hirudinea includes leeches, such as the medicinal leech, Hirudo medicinalis, which is effective at increasing blood circulation and breaking up blood clots. (a) Which type of diseases can be treated with Hirudo medicinalis and what is the role of blood clotting in such diseases? ..................................................................................................................................... ..................................................................................................................................... ..................................................................................................................................... ..................................................................................................................................... [3] (b) The table below shows lifestyle habits leading to CVDs. Complete the table by writing in the name, the role or the mechanism of the habit leading to CVDs in the empty boxes. . [4] (Total 7 marks) alevelbiology.co.uk 15. In a study, data on the cholesterol levels and blood pressure for different adult populations in America were collected. The mean cholesterol level and the percentage of each population with high blood pressure were calculated. The results are shown in the table below. Adult population (ethnic groups) Mean cholesterol level / mg dm–3 Percentage of population with high blood pressure (%) Black and African American 204 40 White American 206 27 Mexican American 205 29 American Indian and Alaskan Native Statistically unreliable data Statistically unreliable data (a) There could be a causal link or correlation between high blood pressure and the other variables shown in the table. Distinguish between the terms causation and correlation. ..................................................................................................................................... ..................................................................................................................................... ..................................................................................................................................... ..................................................................................................................................... ..................................................................................................................................... (2) (b) Suggest one reason why the data on the American Indian and Alaskan Native population are described as statistically unreliable. ..................................................................................................................................... ..................................................................................................................................... ..................................................................................................................................... (1) alevelbiology.co.uk (c) Using the information in the table above, describe the relationship between ethnic group, cholesterol levels and the percentage of the population with high blood pressure. ..................................................................................................................................... ..................................................................................................................................... ..................................................................................................................................... ..................................................................................................................................... (2) (d) A student concluded from the results for gender, shown in the table below, that higher cholesterol levels cause lower blood pressure. Adult population (gender) Mean cholesterol level / mg Percentage of population dm–3 with high blood pressure (%) Female 207 26 Male 204 30 Using the information in both tables, explain why this is not a valid conclusion. ..................................................................................................................................... ..................................................................................................................................... ..................................................................................................................................... ..................................................................................................................................... ..................................................................................................................................... (3) [Total 8 marks] alevelbiology.co.uk 16. Coronary heart disease (CHD) is a major cause of death in developed countries, and accounts for over 160 000 deaths each year in the United Kingdom. One of the main causes of CHD is atherosclerosis, a condition in which lipids and connective tissue build up on the inside wall of blood vessels. (a) State two consequences of atherosclerosis which may lead to the development of CHD in an individual. 1................................................................................................................................... ..................................................................................................................................... 2................................................................................................................................... ..................................................................................................................................... (2) (b) The table shows deaths from coronary heart disease as a percentage of all deaths in the United Kingdom in 1983. Percentage of all deaths Age / years Males Females 0– 14 4 3 15– 24 7 10 25– 34 15 14 35– 44 37 18 45– 54 53 26 55– 64 53 37 65– 74 53 50 75 and over 51 56 With reference to the data in the table, compare the percentage of deaths from CHD in males and females. ..................................................................................................................................... ..................................................................................................................................... ..................................................................................................................................... ..................................................................................................................................... (3) (Total 5 marks) alevelbiology.co.uk 17. Several risk factors influence the onset of coronary heart disease (CHD), including high blood cholesterol level, high blood pressure and smoking. The chart shows the effect of combining these three factors on the incidence of CHD. (a) Describe the effect on the incidence of CHD of increasing the number of risk factors. ..................................................................................................................................... ..................................................................................................................................... ..................................................................................................................................... ..................................................................................................................................... (3) b) Explain how each of these risk factors can influence the onset of CHD. High blood cholesterol ..................................................................................................................................... ..................................................................................................................................... ................................................................................................................................... High blood pressure ..................................................................................................................................... ..................................................................................................................................... ..................................................................................................................................... Smoking ..................................................................................................................................... ..................................................................................................................................... ..................................................................................................................................... (6) (Total 9 marks) alevelbiology.co.uk 18. Obesity is a significant problem in western countries and an increasing problem in other parts of the world. An obese person has a greater risk of developing heart disease. Body Mass Index (BMI) is one measure used to help decide if a person’s weight is healthy for their height. The BMI can be calculated by dividing mass in kilograms by height in metres squared. A table is then used to judge if the BMI is reasonable or not. A copy of this table is shown below. BMI range Less than 18.5 18.5 to 24.9 25.0 to 29.9 30.0 to 39.9 40.0 or above Description Underweight Healthy weight Overweight Obese Morbidly obese (a) A man was concerned that he was overweight and at risk of coronary heart disease. He was 1.8 m tall and had a mass of 83.0 kg. (i) Calculate the man’s body mass index (BMI) using the formula below. BMI = Answer ................................................... (2) (ii) Using the information in the table, interpret this man’s BMI. ................................................................................................................... ................................................................................................................... ................................................................................................................... ................................................................................................................... ................................................................................................................... (2) alevelbiology.co.uk (b) Using the pie chart given above, discuss whether or not a woman in her early 30s with a BMI of 32.5 should be concerned about her risk of dying due to cardiovascular diseases. ..................................................................................................................................... ..................................................................................................................................... ..................................................................................................................................... ..................................................................................................................................... ..................................................................................................................................... ..................................................................................................................................... (2) (Total 6 marks) 19. Name two diseases associated with obesity. 1................................................................................................................................... 2................................................................................................................................... [Total 2 marks] alevelbiology.co.uk 20. A way of determining whether a person is underweight or overweight is to use a graph showing the relationship between height and body mass. The figure below is an example of this type of graph. (i) Using the graph above, state the category into which a female who has a body mass of 69 kg and a height of 1.67 m is placed. ..................................................................................................................................... [1] (ii) There are many factors that determine the category into which a person is placed. The graph above does not take into account all of these factors. Suggest why the female in (i) might be placed in the wrong category. ..................................................................................................................................... ..................................................................................................................................... ..................................................................................................................................... ..................................................................................................................................... [2] [Total 3 marks] alevelbiology.co.uk
