Oct/Nov 2020

The diagram illustrates the structure of a cell taken from a leaf of a green plant. What are the numbered parts in the cell?

Cell structure and function

A disease may cause weakness, fatigue, aching and swollen joints, and gums that are swollen and soft. Which food is used to treat this disease?

Diet

Which diagram indicates the location of phloem tissue in a herbaceous, dicotyledonous root?

Specialised cells, tissues and organs

The diagram shows a section of a leaf. Which arrows indicate translocation and transpiration?

Transpiration and translocation

During blood clotting, the \(\ldots\ldots 1 \ldots\ldots\) cause \(\ldots\ldots 2 \ldots\ldots\) to change into \(\ldots\ldots 3 \ldots\ldots\), and this then makes a clot. Which words finish the statement about blood clotting?

Blood

The diagram illustrates part of a capillary. Which arrow indicates the formation of tissue fluid?

Blood vessels

Which row identifies possible causes of coronary heart disease?

Heart

Which products are formed during anaerobic respiration in yeast?

Anaerobic respiration

The diagram illustrates apparatus set up to investigate respiration. Which change would be observed, and what is the explanation?

Respiration

The diagram illustrates the rib cage and some of the muscles used in breathing from a side view. What occurs when the intercostal muscles in the diagram contract?

Human gas exchange

In dialysis, substances including glucose, mineral salts, urea and water pass between the patient’s blood and the dialysis fluid. Which processes cause these movements?

Diffusion and osmosis

The diagram presents three plant cells, P, Q and R. The arrows indicate the direction in which water moves by osmosis. What is the correct sequence of water potential in the cells, from highest to lowest?

Diffusion and osmosis

Which organs in humans take part in keeping body temperature constant?

Temperature control

The diagram shows a cross-section of the brain. Which labelled part is the hypothalamus?

Mammalian nervous system

The diagram illustrates a cross-section of the eye. When the person looks downward and focuses on their mobile phone, what is the condition of structures P and R?

Mammalian sense organs

What is one indication of diabetes mellitus?

Blood glucose control

The diagram illustrates the bones in the human arm. Which bone is marked X?

Specialised cells, tissues and organs

For which illnesses can antibiotics be used as effective treatments?

Antibiotics

The table presents the features of four microorganisms. Which one might be a virus?

Features of organisms

Which comparison statement about the production of single cell protein and the production of protein in meat is incorrect?

Biotechnology

Which statement is used to describe relationships in ecosystems?

Ecosystems and biodiversity

Mealybugs are tiny insects that feed on crops such as mango and coffee. They harm the crops and lower the yield and profits for farmers. Lacewing insects and ladybird beetles both feed on mealybugs. Which row shows the positions of some of the organisms in this food chain?

Energy flow

An experiment was used to determine the rate at which plants absorb magnesium ions from solution. One plant was treated with a poison that prevents respiration, whereas another plant was left untreated. The graph shows the results. By what process are the magnesium ions being taken up by the plants at points N and P?

Active transport

The diagram displays the carbon cycle. What is process X?

Nutrient cycles

Three statements about malarial parasites are given. Which methods may be used to control malaria?

Disease

Which property would be unwanted in an insecticide?

Effects of humans on ecosystems

The diagram illustrates a part of a flower. In which part are the male gametes produced?

Sexual reproduction in plants

Which condition is not essential for seed germination?

Sexual reproduction in plants

What is one benefit to a baby of breast-feeding rather than bottle feeding?

Immunity

The diagram represents a calendar covering 33 days in February and March. A girl with a regular menstrual cycle lasting 28 days starts menstruating on 5 February. Between which dates would the progesterone concentration in her blood increase most quickly?

Sexual reproduction in humans

In one mouse species, fur colour may be either black or white. Two black female mice were each allowed to mate with the same black male. One female produced nine offspring, all of them black. The other female produced seven offspring, five black and two white. One of the white mice was male, and is allowed to mate with a heterozygous female. What phenotypic ratio is expected in their offspring?

Inheritance

The diagram illustrates the blood group phenotypes of several family members. Which member of the F1 generation has to be heterozygous for the codominant alleles?

Inheritance

The diagram illustrates how a human characteristic, $X$, is distributed within the population. What is characteristic $X$?

Variation

Starch digestion takes place in the mouth cavity and in the duodenum, but it does not continue in the stomach. Why is this?

Effects of temperature and pH

Which of the following statements about using bacteria to make human insulin are correct?

Genetic modification

Which row gives the correct number of molecules, for each substance consumed and formed, during photosynthesis?

Photosynthesis

By what route do carbon dioxide and water enter a leaf?

Leaf structure

The graph illustrates how the rate of photosynthesis changes as light intensity changes at two different temperatures. All other variables remain unchanged. In which parts of the graph does light intensity limit the rate of photosynthesis?

Photosynthesis

The diagram illustrates the human alimentary canal. In which section does protein digestion start?

Human digestive system

Blood travels from the small intestine in the hepatic portal vein. After that, where does the blood travel to, and what can happen there?

Absorption and assimilation

The diagram illustrates a section of a plant cell. Which structure regulates the entry of substances into the cell?

Cell structure and function

Signs of this disease include weakness, tiredness, painful and swollen joints, and gums that are swollen and soft. Which food is used to treat this disease?

Diet

The diagrams illustrate transverse sections of a dicotyledonous root and stem. Which tissues are involved in the movement of sugar?

Transpiration and translocation

The diagram shows a cut plant shoot placed in a container of water. What will prevent water from moving up this stem?

Transpiration and translocation

Which route does oxygenated blood take through the human body?

Circulatory system

The graph illustrates a person's pulse rate across a time interval during which they rest, ride an exercise bike, and then rest once more. At what point did the person cease pedalling?

Heart

Which row indicates the blood pressures in an artery, a capillary and a vein?

Blood vessels

Anaerobic respiration occurs when which substance is absent?

Anaerobic respiration

The apparatus illustrated is used to produce alcohol by anaerobic respiration. What do P, Q and R represent?

Anaerobic respiration

The diagram illustrates the rib cage and some of the muscles used in breathing, viewed from the side. What happens when the intercostal muscles shown in the diagram contract?

Human gas exchange

The diagram illustrates a dialysis machine. Which substance would not be found in a sample of the dialysis fluid collected from point X?

Urinary system

Which of the following statements about diffusion are correct?

Diffusion and osmosis

Which layer of the skin plays a major role in insulating the human body?

Temperature control

What is the meaning of a reflex action?

Mammalian nervous system

A person is viewing some hills in the distance. Which row shows the condition of the lenses, ciliary muscles and suspensory ligaments in her eyes?

Mammalian sense organs

What is one symptom of diabetes mellitus?

Blood glucose control

The diagram illustrates the bones in the forelimb. Which labels indicate the attachment points of the muscle that extends the hinge joint?

Specialised cells, tissues and organs

Which one of these diseases is treated effectively using antibiotics?

Antibiotics

The table presents the features of four microorganisms. Which of them could be a virus?

Features of organisms

A fermenter is used to produce penicillin. Why is it necessary to keep stirring continuously during fermentation?

Biotechnology

Which of the following statements describes relationships in ecosystems?

Ecosystems and biodiversity

The diagram shows a food web of organisms in a pond. Which organism is a herbivore as well as a carnivore?

Energy flow

An experiment investigated the speed at which plants absorb magnesium ions from a solution. One plant was treated with a poison that prevents respiration, while the other plant was kept unchanged. The graph displays the outcomes. How are the magnesium ions being taken up by the plants at points N and P?

Active transport

The diagram illustrates the nitrogen cycle. Which stage is performed by nitrifying bacteria?

Nutrient cycles

Three statements concerning malarial parasites are given. Which methods may be used to control malaria?

Disease

Which characteristic would be unwanted in an insecticide?

Effects of humans on ecosystems

The diagram depicts a flower split in two. Which two parts of the flower make haploid gametes?

Sexual reproduction in plants

The diagram shows a cross-section of a non-endospermic seed. Which structures grow into the mature plant?

Sexual reproduction in plants

Which row gives a cause, a symptom and a treatment for syphilis in males?

Disease

The diagram illustrates how the thickness of the lining of the uterus changes over one menstrual cycle. At what point would the levels of progesterone and LH be at their highest?

Mammalian hormones

In a species of mouse, fur colour may be black or white. Two black female mice were each mated with the same black male. One female produced nine offspring, all black. The other female produced seven offspring, of which five were black and two were white. One of the white mice was male and is then allowed to mate with a heterozygous female. What phenotype ratio is expected among their offspring?

Inheritance

The diagram illustrates the blood group phenotypes for several individuals in a family. Which member of the F1 generation is certain to be heterozygous for the codominant alleles?

Inheritance

Which human characteristic displays discontinuous variation?

Variation

Starch digestion takes place in the mouth cavity and in the duodenum, but it comes to an end in the stomach. What is the reason for this?

Effects of temperature and pH

A farmer aims to breed oranges that are extra-large and sweet by selective breeding. From the information in the table, which plant types should the farmer choose for breeding?

Selection

Which part of a leaf takes in and uses carbon dioxide from the air?

Leaf structure

In what way do carbon dioxide and water enter a leaf?

Leaf structure

The graph illustrates how the rate of photosynthesis changes with light intensity at two different temperatures. All other variables are kept constant. At which parts of the graph is light intensity the factor limiting the rate of photosynthesis?

Photosynthesis

Which substrates and end products are linked to amylase and lipase?

Enzyme action

What is the principal role of the villi in the ileum?

Absorption and assimilation

The diagram shows how the human alimentary canal would appear if it were taken out of a person and then laid out straight.

Human digestive system

Corals consist of many tiny animals that live together in the sea, and their skeletons build coral reefs. Inside the cells of these animals are microscopic green, plant-like organisms known as algae.

Photosynthesis

Atmospheric air is made up of several gases.

Effects of humans on ecosystems

The diagram illustrates two identical cigarettes before smoking and one cigarette after smoking.

Disease

State the substance that plants absorb by means of osmosis.

Diffusion and osmosis

State the roles of the aorta and the vena cava and explain how each is adapted for its role.

Blood vessels

Explain how the energy that first comes from the Sun is ultimately used to drive the muscles of a lion when it runs.

Energy flow

Explain why plants grown commercially are often reproduced by asexual methods.

Asexual and sexual reproduction

Describe, with examples, what the term mutation means. Name factors that may increase the rate of mutation.

Selection

The flow chart outlines the stages in the life cycle of a flowering plant.

Sexual reproduction in plants

In 1931, a scientist was transferring powdered PTC into a bottle. A small quantity of the powder was accidentally released into the air. Soon after, another scientist in the same room reported a bitter taste in her mouth from the powder floating in the air.

Mammalian sense organs

When an apple fruit is sliced open, the exposed surface of the apple tissue turns brown quickly and is less likely to be eaten. The diagram shows this colour change.

Enzyme action

Hydroponics is a method for raising plants without soil. The diagram shows plants being grown by hydroponics.

Uptake and transport of water and ions

The diagram illustrates the total amount of water that enters and leaves the organs of the human alimentary canal in one day.

Absorption and assimilation

The diagram depicts a vertical cross-section of human skin in a hot setting.

Temperature control

The kidneys are organs for excretion.

Urinary system

Describe the main functions of the cerebrum in coordinating and regulating bodily functions.

Mammalian nervous system

Explain how a surgical procedure can be used as an effective form of birth control in a man and in a woman.

Sexual reproduction in humans