May/June 2016

Yeast, sugar and water are combined in a test-tube. The diagrams illustrate the test-tube at the beginning and one hour later. Which process is responsible for this change?

Anaerobic respiration

Which graph illustrates how temperature affects enzyme activity?

Enzymes

The diagram shows enzyme action. Which parts are W, X and Y in this chemical reaction?

Enzymes

In an experiment on photosynthesis, a plant is placed in bright sunlight for several hours. A leaf is then taken from the plant and tested for starch using iodine solution. The diagram shows the leaf from the plant that was used in the experiment. Which diagram shows the result of the experiment?

Photosynthesis

What substance required for protein synthesis is transported into a leaf from the stem?

Translocation

Which kind of food is absorbed by the body without first being digested?

Absorption

The diagram illustrates the human alimentary canal. In which structure is most glucose taken up into the blood?

Absorption

Which dietary component is least likely to be lacking in a meat-free diet?

Diet

Which graph makes it clearest what happens to the rate of transpiration as humidity increases?

Transpiration

The diagram shows a potted plant and that same plant after 24 hours. What is responsible for the change in the plant’s appearance?

Transpiration

Which substances are dissolved in the plasma of human blood?

Blood

What term is used for a group of individuals capable of reproducing to produce fertile offspring?

Concept and uses of classification systems

Which chamber of the heart has the thickest muscular wall?

Heart

Approximately what percentage of oxygen is present in expired air?

Gas exchange in humans

Relative to atmospheric air, the air exhaled by a human contains

Gas exchange in humans

What is made by anaerobic respiration in yeast?

Anaerobic respiration

What word equation represents aerobic respiration in plants?

Aerobic respiration

In which part of the body is urea produced?

Excretion in humans

The diagram shows a simple reflex arc. What is the order of nerve cells through which an impulse travels during a reflex action?

Coordination and response

The diagram depicts a neurone. Which structures might be present at X and Y?

Coordination and response

How will strenuous exercise affect the volume of water lost via the skin and the kidneys?

Homeostasis

Which organ is most commonly harmed by regularly consuming too much alcohol?

Drugs

Refer to the key to identify the animal shown in the diagram.

Concept and uses of classification systems

When a baby is delivered, the following events take place. 1 rupture of the amniotic sac 2 contraction of muscles in the wall of the uterus 3 severing of the umbilical cord In what sequence do these events normally happen?

Sexual reproduction in humans

The diagrams illustrate pollen grains from three different plant species as seen through a microscope. All of the diagrams are drawn to the same scale. Which pollen grains are involved in insect-pollination?

Sexual reproduction in plants

The diagram illustrates the human female reproductive system. If a woman uses a femidom as a contraceptive, at what location would it be inserted?

Sexual reproduction in humans

Cells arise when existing cells divide. Four different cells are shown below. Which cell is formed by meiosis?

Meiosis

Albinism is a condition passed on through inheritance in which pigment fails to develop in the skin, hair and eyes. The albinism allele is recessive. What is the probability that parents who are albino will have an albino child?

Monohybrid inheritance

What is the name for the observable characteristics of an organism?

Features of organisms

Which of the following is not a characteristic of natural selection?

Selection

The graph illustrates a population growth curve. Which factors would make region X on the graph become steeper?

Populations

The diagram represents a straightforward food chain. green plant $\rightarrow$ herbivore $\rightarrow$ carnivore If a disease reduces the number of herbivores, what effect will this have on the numbers of green plants and carnivores?

Food chains and food webs

A gene for insulin is isolated from a human cell and introduced into a bacterium. The bacterium can then produce human insulin. What is this process known as?

Genetic modification

Which row correctly pairs the cell membrane and cell wall of a palisade cell with their functions?

Cell structure

The diagram indicates where four farms are located and the nitrate concentrations measured at various points along a river. Which farm is most likely to have been applying excess fertiliser to its land?

Pollution

In a plant, what structure is made up of a cluster of xylem vessels?

Xylem and phloem

What functions do xylem vessels carry out?

Xylem and phloem

Active transport is the process of moving

Active transport

The diagram illustrates an experiment used to show the movement of molecules. After one hour, the water in the beaker had become red. What is the most likely explanation for this colour change?

Diffusion

Small molecules act as the fundamental units used to synthesise large food molecules. Which statement is correct?

Biological molecules

A test-tube contains yeast, sugar and water mixed together. The diagrams illustrate the test-tube at the beginning and again after one hour. Which process brings about this change?

Anaerobic respiration

When a substance is combined with meat, amino acids are formed. What is this substance?

Enzymes

Which graph illustrates how temperature affects enzyme activity?

Enzymes

Which two substances are formed during photosynthesis?

Photosynthesis

In a photosynthesis experiment, a plant is kept in bright sunlight for several hours. After that, a leaf is taken from the plant and tested with iodine solution to check for starch. The diagram shows the leaf from the plant that was used in the experiment. Which diagram shows the outcome of the experiment?

Photosynthesis

Which category of food is absorbed by the body without first being digested?

Absorption

The bacterium Salmonella enterica can lead to severe food poisoning, and the lining of the alimentary canal may become damaged. In such cases, the absorption of digested food products cannot occur easily. Which part of the alimentary canal is most affected?

Absorption

The diagram illustrates several organs of the human body. In which organs does the digestion of proteins occur?

Chemical digestion

The diagram illustrates a potted plant and the same plant 24 hours later. What causes the change in the plant’s appearance?

Transpiration

Which graph most clearly shows how the rate of transpiration will change as humidity increases?

Transpiration

The diagram illustrates the human heart together with some of the blood vessels attached to it. Before the blood in W arrives at Z, it must

Heart

The scientific name of a rat is Rattus rattus. What do the two parts of this name denote?

Concept and uses of classification systems

What substances are dissolved in human blood plasma?

Blood

What are the approximate percentages of oxygen and carbon dioxide found in atmospheric air?

Gas exchange in humans

Along which pathway does air travel from the lungs of a human to the atmosphere?

Gas exchange in humans

When aerobic respiration occurs, glucose is broken down. What is produced in this process?

Aerobic respiration

Which processes are dependent on enzyme action?

Enzymes

Which diet will lead the liver to produce the greatest amount of urea?

Excretion in humans

The diagram shows a simple reflex arc. What is the order of nerve cells along which an impulse travels during a reflex action?

Coordination and response

The diagram illustrates a cross-section of an eye. Which part controls the amount of light entering the pupil?

Sense organs

What effects does adrenaline have?

Hormones

Which organ metabolises heroin and alcohol?

Drugs

The diagram depicts a bird that lives close to rivers. Use the key to identify the bird shown in the diagram.

Concept and uses of classification systems

Under what conditions will seeds germinate most quickly?

Sexual reproduction in plants

What features does asexual reproduction have?

Asexual reproduction

The diagram shows processes involved in sexual reproduction. Which processes are shown by stages Q and R?

Sexual reproduction

What is the term for the observable characteristics of an organism?

Features of organisms

Which structure is present in the nucleus of a body cell in a woman?

Chromosomes, genes and proteins

What does the term mutation mean?

Chromosomes, genes and proteins

In the food chain shown below, a viral disease reduces the snake population to half. grass $\rightarrow$ locusts $\rightarrow$ snakes $\rightarrow$ eagles What impact does this have on the other organisms in the food chain?

Populations

Which one below is an example of a population?

Populations

The diagram shows the carbon cycle. Which process does arrow X show?

Nutrient cycles

A gene coding for insulin is removed from a human cell and inserted into a bacterium. The bacterium is then able to produce human insulin. What is this process known as?

Genetic modification

In a plant, what structure is produced by a cluster of xylem vessels?

Xylem and phloem

The diagram shows the locations of four farms and the nitrate concentrations at different points along a river. Which farm is most likely to have been using too much fertiliser on its land?

Pollution

The diagram illustrates a palisade mesophyll cell. Which structure is absent from an animal cell?

Cell structure

Which statement is true of phloem but not of xylem?

Xylem and phloem

What causes oxygen to diffuse into the blood from an alveolus in the lungs?

Gas exchange in humans

The diagram shows water and sugar molecules positioned on opposite sides of a partially permeable membrane. What occurs during osmosis?

Osmosis

Small molecules act as the starting units in the formation of large food molecules. Which statement below is correct?

Biological molecules

Yeast, sugar and water are combined in a test-tube. The diagrams show the test-tube at the beginning and again after one hour. Which process is responsible for this change?

Anaerobic respiration

The diagram shows a chemical reaction in which two reactants combine to make a product. Which diagram would represent the enzyme for this reaction?

Enzymes

Which graph illustrates how temperature affects enzyme activity?

Enzymes

Four test-tubes are arranged as shown in the diagram and kept in direct sunlight. After several hours, which test-tube has the greatest amount of dissolved oxygen?

Photosynthesis

In an experiment on photosynthesis, a plant is kept in strong sunlight for several hours. After that, a leaf is taken from the plant and tested for starch with iodine solution. The diagram shows the leaf from the plant used in the experiment. Which diagram represents the outcome of the experiment?

Photosynthesis

Which organ is responsible for producing amylase?

Chemical digestion

Which treatment is most suitable for a person suffering from persistent diarrhoea?

Diseases and immunity

Which kind of food is absorbed by the body without being digested first?

Absorption

Which graph best shows how the rate of transpiration changes as humidity rises?

Transpiration

The diagram compares a potted plant with the same plant after 24 hours. What is responsible for the change in the plant’s appearance?

Transpiration

Which blood vessel contains a high concentration of carbon dioxide, a low concentration of oxygen, and a high blood pressure?

Blood vessels

Phototropism illustrates which two characteristics of living organisms?

Characteristics of living organisms

Which substances are present in dissolved form in human blood plasma?

Blood

What route does carbon dioxide take as it leaves the lungs?

Gas exchange in humans

In certain amphibians, gas exchange takes place across the entire skin surface. Which characteristics are the skin surface most likely to have?

Gas exchange in humans

Which statement correctly describes anaerobic respiration in yeast?

Anaerobic respiration

Give one example of excretion in mammals.

Excretion in humans

Someone has remained in a room at $35^{\circ}\text{C}$ for $30$ minutes. What effect would then drinking several glasses of iced water have?

Homeostasis

The diagram shows a simple reflex arc. In what order do the nerve cells carry the impulse in a reflex action?

Coordination and response

Give one example of gravitropism.

Tropic responses

Which organ releases a hormone?

Hormones

What is one effect of drinking too much alcohol?

Drugs

The table displays the scientific names and the common names for four plants. Althaea officinalis - marsh mallow Hottonia palustris - water violet Viola palustris - marsh violet Viola tricolor - wild pansy Which word in their names indicates that two of the plants have the highest number of features in common?

Concept and uses of classification systems

The table sets out the conditions supplied for four groups of seeds. Which of the seeds germinate?

Sexual reproduction in plants

The diagram illustrates the reproductive organs of a human female. What is the name of structure X?

Sexual reproduction in humans

People who own race horses that perform well hope the young will resemble their parents. In what way does a young race horse acquire its characteristics by inheritance?

Chromosomes, genes and proteins

In pea plants, the allele for tall, $T$, is dominant over the allele for dwarf, $t$. Which cross would give plants in the ratio of $1$ tall : $1$ dwarf?

Monohybrid inheritance

What name is given to the characteristics of an organism that can be observed?

Features of organisms

Which human characteristic exhibits discontinuous variation?

Variation

The graph illustrates how the world’s human population has grown since 1630. What was the greatest length of time needed for the population to double?

Populations

The diagram illustrates a food chain. $ \text{tree} \rightarrow \text{small insects} \rightarrow \text{small birds} \rightarrow \text{birds of prey} $ Which pyramid of numbers is correct for this food chain?

Food chains and food webs

Which process is not included in the water cycle?

Nutrient cycles

A gene coding for insulin is removed from a human cell and inserted into a bacterium. The bacterium is then able to produce human insulin. What is this process called?

Genetic modification

What is the correct sequence of the following structures in order of increasing size, from the smallest to the largest?

Size of specimens

The diagram indicates where four farms are located and gives the nitrate concentrations at various locations along a river. Which farm is most likely to have been applying excessive fertiliser to its land?

Pollution

In a plant, what structure is produced by a collection of xylem vessels?

Xylem and phloem

The shaded region in the diagram shows structures that occur in both plant cells and animal cells. Which cell structure is in the shaded region?

Cell structure

As shown, a jar filled with air was turned upside down and positioned above a jar that contained a brown gas. Which process has occurred?

Diffusion

Which statement explains how young plants are supported?

Water uptake

In the synthesis of large food molecules, small molecules act as the basic units. Which statement is correct?

Biological molecules