Biology 5090 · O Level
May/June 2019
98 questions from this paper, with worked solutions and instant marking.
The diagram depicts a cell from a plant leaf and a cell from an animal’s skin. Which part would turn blue-black when iodine solution is added?
Biological molecules
Which statement best explains the function of the stomach?
Human digestive system
Which statement most accurately describes how water moves through a plant stem?
Transpiration and translocation
A plant was put into water that contained black dye. After $24$ hours, the plant was taken out and cross-sections were cut from the root and the stem. Which diagram represents the results?
Uptake and transport of water and ions
In a muscle, which two substances undergo a net transfer from the plasma to the tissue fluid?
Circulatory system
A patient breathes in a drug. Which chamber of the patient’s heart would receive the blood carrying the drug first?
Heart
Which table indicates the vessels that transport blood to and from the heart, liver and lungs?
Blood vessels
Which of the following statements about anaerobic respiration in humans is correct?
Anaerobic respiration
The diagram illustrates the human gas exchange system. Which label indicates where the larynx is located?
Human gas exchange
The graph illustrates how the pressure and volume inside the lungs vary during one full breath. At which point do the muscles of the diaphragm begin to contract?
Human gas exchange
The diagram illustrates the kidneys and the structures connected to them. Which row correctly names P, Q, R and S?
Urinary system
The diagram shows a plant cell after it has been placed in a solution for an hour. What explains the appearance of this cell?
Diffusion and osmosis
Through which process would the body lose the greatest amount of heat on a hot, dry day, when the temperature of the air around it is above body temperature?
Temperature control
What short-term effects does adrenaline have on the body?
Mammalian hormones
In what way does hormonal control usually differ from nervous control?
Mammalian hormones
A girl is standing at a bus stop and looking at a bus moving towards her. What happens to her eyes as the bus comes nearer?
Mammalian sense organs
The diagram illustrates a dog skeleton. Which bone is called the radius?
Specialised cells, tissues and organs
Which statements concerning heroin use are correct?
Disease
What characteristics do bacteria have?
Features of organisms
Which of these can be made using bacteria?
Biotechnology
In the long run, what happens to all the energy present in an ecosystem?
Energy flow
Which statement about the organisms found at the start of food chains is correct?
Energy flow
The diagram shows several cells in the root of a plant taking up water from the soil. In what way does the water potential of cell 2 differ from the water potentials of cells 1 and 3?
Uptake and transport of water and ions
The diagram illustrates part of the carbon cycle. What are the processes X and X?
Nutrient cycles
In what way does an anti-malarial drug control malaria?
Disease
A large number of the world’s main rivers are dammed to regulate water flow. Which result of this would be beneficial to humans in the long term?
Effects of humans on ecosystems
After the pollen tube has entered which structure does a male gamete leave it?
Sexual reproduction in plants
What does genetically identical mean?
Variation
The diagram illustrates several stages of human reproduction, beginning with ovum (egg) and ending with foetus. In which part of the body does stage 2 take place?
Sexual reproduction in humans
Which row shows the correct match between a hormone and its role in the menstrual cycle?
Mammalian hormones
Two heterozygous plants are crossed. What ratio of homozygous genotypes to heterozygous genotypes is most likely in the offspring?
Inheritance
Which row gives the sex chromosomes when the parents have a baby boy?
Inheritance
Which statement about genetic engineering is incorrect?
Genetic modification
Which statement concerning enzymes is incorrect?
Enzyme action
Which term refers to reproduction among the members of a species that are most suited to their environment?
Selection
How do plant leaves change when nitrate ions are deficient?
Mineral nutrition
The graphs illustrate how two different conditions influence the rate of photosynthesis. Which conditions are changed in graphs 1 and 2?
Photosynthesis
A plant has leaves that contain both green regions and white regions. On one leaf, part of the surface is covered with aluminium foil so that light cannot reach it. The plant is then kept beneath a lamp for 24 hours. After this period, discs are removed from the leaf areas shown and examined using iodine solution. Which leaf discs will turn blue-black when iodine solution is added?
Photosynthesis
The diagram illustrates a section of the wall of the small intestine. Into which structure are most of the lipid components of the diet absorbed so that they can be carried to the rest of the body?
Absorption and assimilation
The diagram illustrates how the human teeth are arranged in the lower jaw. Which tooth is an incisor?
Human digestive system
Which two structures occur in every plant epidermal cell?
Specialised cells, tissues and organs
The lengths of three sections of the human alimentary canal are given below. Section P: $350\,\text{cm}$ Section Q: $150\,\text{cm}$ Section R: $26\,\text{cm}$ Which row names these sections correctly?
Human digestive system
Which option gives the best description of how water moves through a plant stem?
Transpiration and translocation
A plant was kept in water mixed with black dye. After $24$ hours, the plant was removed and sections were cut from the root and the stem. Which diagram shows the results?
Uptake and transport of water and ions
In a muscle, which two substances undergo net transfer from the plasma into the tissue fluid?
Circulatory system
Via which valve does blood move as it leaves the right ventricle, and which structure does it then enter?
Heart
Which statement concerning white blood cells is correct?
Blood
During the night, the air temperature is $3\,^{\circ}\text{C}$. Someone goes outdoors for $30$ minutes, and their body temperature decreases. What could explain this change in temperature?
Temperature control
The table gives the percentages of four gases in inspired air and expired air. Which gas is carbon dioxide?
Human gas exchange
The graph illustrates how lung pressure and volume vary over one full breath. At which point do the diaphragm muscles begin to contract?
Human gas exchange
In what way is the blood in the renal vein different in composition from the blood in the renal artery?
Urinary system
Which process happens only through diffusion?
Diffusion and osmosis
What happens to an athlete's skin during a long run?
Temperature control
Which statement gives an example of a simple reflex action in an arm or a leg?
Mammalian nervous system
Which statement is correct about the formation of urea?
Excretion
What occurs when a person looks at something close by?
Mammalian sense organs
The diagram shows the bones of the human forelimb. Which bone is the radius?
Specialised cells, tissues and organs
Which disease is closely linked to cigarette smoking?
Disease
What are the optimum conditions in a fermenter for the large-scale production of penicillin?
Biotechnology
Waste products from microorganisms are used in the making of bread and yoghurt. Which waste products from microorganisms are involved in these processes?
Anaerobic respiration
What ultimately becomes of all the energy in an ecosystem?
Energy flow
Which statement correctly describes the organisms found at the start of food chains?
Energy flow
The diagram shows a group of cells in the root of a plant that is taking up water from the soil. In what way is the water potential of the cell labelled 2 different from the water potentials of the cells labelled 1 and 3?
Diffusion and osmosis
The diagram illustrates part of the carbon cycle. Which processes are X and Y?
Nutrient cycles
Which of the following statements about mosquitoes are correct?
Features of organisms
The following are some consequences of deforestation: 1 fewer animal habitats; 2 reduced uptake of carbon dioxide during photosynthesis; 3 burning that releases gases into the atmosphere; 4 soil erosion and the loss of minerals needed for plant growth. Which two consequences are most likely to lead to global warming?
Effects of humans on ecosystems
After the pollen tube has entered which structure does a male gamete leave the pollen tube?
Sexual reproduction in plants
1000 seeds were put into moist soil, kept in the dark, at $25\,^{\circ}\text{C}$ for 4 days. On each day, the same number of germinating seeds was taken out, dried, and their components separated and weighed. Which statements are supported by the data from this investigation?
Aerobic respiration
What sign of syphilis can appear many years after infection if treatment is not given?
Disease
The diagram illustrates several stages in the asexual reproduction of a single-celled organism. Which row correctly indicates the relative quantities of DNA in the cells V, W, X, Y and Z?
Nuclear division
When two heterozygous plants are crossed, what is the probable ratio of homozygous genotypes to heterozygous genotypes among the offspring?
Inheritance
The diagram presents a family tree, with the blood groups of certain individuals marked. What blood groups could the numbered individuals have?
Inheritance
Which plant genetic engineering product is associated with farming methods that could reduce biodiversity?
Genetic modification
Which graph illustrates how temperature affects the rate of a reaction catalysed by amylase?
Effects of temperature and pH
Which term is used for reproduction among the members of a species that are most well adapted to their environment?
Selection
How does a shortage of nitrate ions affect plant leaves?
Mineral nutrition
Which word equation represents photosynthesis?
Photosynthesis
A student carried out an experiment to find out whether chlorophyll is necessary for photosynthesis. Which plant would be suitable for this experiment?
Photosynthesis
The diagram depicts part of the wall of the small intestine. Into which structure are most dietary lipid components absorbed before being carried to the rest of the body?
Absorption and assimilation
A surgical procedure is used to remove the gall bladder. What are patients who have had this procedure unable to do?
Human digestive system
A seal is a mammal that lives mainly in the sea. Its breathing and respiration are very much like those of a human, but when it dives to chase and catch fish, it can remain underwater for as long as 20 minutes. The graph shows how the percentage concentrations of oxygen and carbon dioxide, together with the concentration of lactic acid, change in a seal’s blood over a 40 minute period while it dives to hunt and catch fish.
Anaerobic respiration
The diagram displays three insect varieties, C, D and E, from the same species, together with three leaf patterns, F, G and H, from the same plant species, which the insect feeds on.
Selection
The diagram illustrates a seed just after planting.
Sexual reproduction in plants
The diagram illustrates different stages in the life cycle of this same plant.
Sexual reproduction in plants
The diagram indicates where several organs are located in the human body. These organs could be present in a male, a female, or in both.
Mammalian hormones
Define osmosis and explain why it counts as a distinctive form of diffusion.
Diffusion and osmosis
Describe how named toxic materials and metabolic waste products are removed from the human body.
Excretion
Describe and compare a gene with an allele.
Variation
Describe and compare the characteristics of antibodies and antibiotics.
Immunity
Food supplements are materials that are often added to a person's diet. They may come as tablets. The diagram shows the label on a food supplement. Use together with a balanced diet. Ingredients: • Amylase • Cellulase • Lipase • Protease This supplement could be suitable for a person whose pancreas is not making enough of some of the ingredients listed on the label.
Enzyme action
The diagram illustrates the layout of a kind of bacterium and outlines how that bacterium responds to light.
Cell structure and function
The diagram illustrates the inside of a seed from a pea plant. Seeds produced by a pea plant are non-endospermic.
Inheritance
The photograph depicts a species of tree frog. Every tree frog in this species is coloured either grey or green.
Selection
The diagram illustrates the carbon cycle.
Nutrient cycles
The diagram presents the heart’s internal layout as seen from the front, together with the blood vessels linked to it.
Heart
The nervous system controls and coordinates body activities.
Mammalian nervous system
Name and describe each process that has to occur in order to move carbon dioxide molecules from a person's blood into the air in the atmosphere.
Human gas exchange
Describe the route taken by water molecules from the soil, through a plant and into the atmosphere.
Transpiration and translocation