50 questions. Try each one, then open the answer to check yourself and read the explanation.
The mouth parts of the housefly are adapted for
Answer: A (lapping and sponging)
The housefly pours saliva on its food and mops up the liquid with its spongy proboscis, so its mouthparts are for lapping and sponging.
The male toad differs from the female by having
Answer: A (vocal sacs)
Only the male toad has vocal sacs, which swell up when it croaks to call females.
Mosses, liverworts and ferns can be grouped together because they
Answer: C (are seedless plants)
Mosses, liverworts and ferns reproduce by spores and never form seeds or flowers.
Spirogyra and Mucor can be grouped together as Thallophyta because
Answer: E (their bodies are made up of thallus and filaments alternatively.)
Thallophytes have a simple body (a thallus) that is not divided into root, stem and leaves; both Spirogyra and Mucor have simple filamentous bodies of this kind.
Which of the following invertebrates does NOT possess antennae?
Answer: E (Spider.)
Spiders (arachnids) have no antennae; they have pedipalps instead. Insects, crustaceans, centipedes and millipedes all have antennae.
Which of the following is INCORRECT? The prothallus of a fern
Answer: C (is the dominant plant)
In ferns the dominant plant is the leafy sporophyte. The prothallus is the small, short-lived gametophyte.
Which of the following cell constituents is NOT common in both plants and animals?
Answer: B (Chloroplasts)
Chloroplasts are found only in plant cells (for photosynthesis). Animal cells have mitochondria, ribosomes, Golgi apparatus and small vacuoles too.
The character-producing factors in living organisms are
Answer: E (genes)
Genes are the units of heredity that control characters; Mendel called them 'factors'.
A mixture of mercurous and mercuric nitrates is added to a food substance. A white precipitate is formed which on gentle heating turns red. The food substance is
Answer: A (protein)
This is Millon's test: a white precipitate that turns red on warming shows that protein is present.
The mammalian organ through which nourishment and oxygen diffuse into a developing embryo is called
Answer: E (placenta)
In the placenta the mother's blood and the embryo's blood come very close, so food and oxygen diffuse across into the embryo's blood.
Fig.1 below represents a quill feather. The structure labelled 'M' is the
Answer: C (superior umbilicus)
M marks the small opening where the quill joins the vane, the superior umbilicus. The inferior umbilicus is the hole at the tip of the quill.
Osmosis can be defined as the movement of
Answer: D (water across a semi-permeable membrane from solution of low concentration to high concentration)
Osmosis is the movement of water molecules through a semi-permeable membrane from a dilute (low concentration) solution to a more concentrated one.
Which of the following statements is NOT true of enzymes? They
Answer: E (can withstand high temperatures.)
Enzymes are proteins, so high temperatures denature them and they stop working.
The dorsal and anal fins of fish are used for
Answer: B (controlling rolling movements)
The unpaired dorsal and anal fins keep the fish upright, stopping it from rolling and yawing.
Exoskeleton is NOT found in the
Answer: C (earthworm)
The earthworm is an annelid with a hydrostatic skeleton. The others are insects or insect larvae with a chitin exoskeleton.
Blood clotting is initiated by
Answer: B (platelets)
At a wound, platelets break down and release thrombokinase, which starts the chain of reactions that forms a clot.
Pepsin is a digestive enzyme which breaks
Answer: C (protein into peptones)
Pepsin, made in the stomach, starts protein digestion by breaking proteins into peptones (shorter chains).
Anaerobic respiration in yeast produces
Answer: A (carbondioxide and ethanol)
Without oxygen, yeast ferments glucose into ethanol (alcohol) and carbon dioxide, releasing a little energy.
Underground stems which grow horizontally through the soil are
Answer: B (rhizomes)
A rhizome, e.g. ginger, is a stem that grows horizontally under the ground. Runners and stolons grow along the surface.
A man with a normal haemoglobin (AA) marries a woman who has sickle-cell haemoglobin (SS). They have a child who has a sickle-cell trait. Which of the following genotypes could be associated with the child's haemoglobin?
Answer: D (AS)
The child gets A from the father and S from the mother, so every child is AS, which is the sickle-cell trait (carrier).
In a Biuret test, some protein was mixed with sodium hydroxide solution. Which of the following chemicals should be added to the mixture for a positive result?
Answer: B (Copper sulphate)
In the Biuret test a few drops of dilute copper sulphate are added to the food and sodium hydroxide; a violet colour shows protein.
The removal of a man's pancreas by surgical operation can affect only the digestion of
Answer: B (starch, protein and fats)
Pancreatic juice contains amylase, trypsin and lipase, so without the pancreas the digestion of starch, proteins and fats is all affected.
The parts used by the tapeworm to fasten itself to the host's intestine are the
Answer: B (hooks and suckers)
The scolex (head) of the tapeworm holds on to the gut wall with its hooks and suckers.
Use Fig. 2 (transverse section of a fowl's egg) to answer this question. The young chick is formed from
Answer: D (2.)
The chick develops from the germinal disc (part 2), the small spot on the yolk where the embryo begins.
Use Fig. 2 (transverse section of a fowl's egg) to answer this question. Which parts provide food for the developing chick?
Answer: C (3 and 4)
The yolk (3) and the albumen or egg white (4) are the food stores used by the growing chick.
Which of the following types of vertebrae occur in equal numbers in the rabbit, rat and man?
Answer: D (Cervical)
Nearly all mammals, from rats to giraffes and man, have seven cervical (neck) vertebrae. The numbers of thoracic, lumbar, sacral and caudal vertebrae vary between species.
Which of the following statements is NOT true of the piliferous layer of a root? It
Answer: B (is the outermost layer of the cortex)
The piliferous layer is the epidermis of the root, which lies outside the cortex and is not part of it. It bears root hairs, has little or no cuticle and is replaced by cork as the root ages.
A flowering plant is monoecious if
Answer: D (the gynoecium and androecium are on the same plant)
A monoecious plant (e.g. maize) bears both male (androecium) and female (gynoecium) parts on the same plant, usually in separate flowers.
How many nuclei are found in a pollen tube during fertilization?
Answer: B (3)
The pollen tube contains one tube nucleus and two male (generative) nuclei, three in all.
Which of the following is NOT a waste product of plants?
Answer: D (Sap)
Sap is the watery fluid in the plant's vessels and cells, not a waste. Tannins, alkaloids, oxygen (from photosynthesis) and carbon dioxide (from respiration) are wastes.
If an animal is very active and has good muscular control, it is likely to have well-developed
Answer: D (cerebellum)
The cerebellum coordinates muscle movement and balance, so it is large in very active animals such as birds.
Which of the following adaptations is NOT concerned with the flight of birds?
Answer: E (Webbed feet)
Webbed feet help water birds to swim, not to fly. The other features reduce drag and weight or power the wings.
The transect method can be used in ecology to show the
Answer: C (distribution of organisms along a line)
In a line transect, a rope is laid across the habitat and the organisms touching it are recorded. It shows how organisms change (are distributed) along that line.
Asexual reproduction does NOT occur in
Answer: E (Rhizopus, Ascaris and Amoeba.)
Ascaris (a roundworm) reproduces only sexually. Every organism in the other groups can reproduce asexually by spores, fission or fragmentation.
Fehling's solution will readily change colour from blue to a reddish colour when it is
Answer: E (Warmed with a solution of reducing sugar.)
Fehling's test needs heat: a reducing sugar warmed with Fehling's solution gives a brick-red precipitate.
The presence of a diastema in the jawbone indicates that the mammal lacks the teeth suitable for
Answer: A (tearing)
The diastema is the gap where canines would be. Canines are for tearing flesh, so herbivores like the rabbit lack them.
Normally the flow of blood is NEVER from
Answer: D (arterioles to the artery)
Blood flows from arteries to arterioles, capillaries, venules and then veins. Flow from arterioles back into an artery would be in the wrong direction.
Heat produced in tissue respiration in plants is
Answer: E (a waste form of energy.)
Respiration releases energy partly as ATP (chemical energy) and partly as heat. Plants do not use this heat to keep warm, so it is lost as waste.
The axial skeleton of a mammal does not include the bones of the
Answer: C (limbs)
The axial skeleton is the skull, vertebral column (neck, back, tail) and ribs. Limb bones belong to the appendicular skeleton.
Which of the following sequences represents the process of blood clotting? 1. Fibrin forms a network of threads 2 Red blood cells are caught and a clot is formed 3. Fibrinogen in plasma changes into soluble fibrin 4 Blood is exposed to air
Answer: B (4,3,1,2)
Blood is first exposed to air at the wound (4), fibrinogen is changed to fibrin (3), fibrin forms a mesh of threads (1) and red cells are trapped in it to make the clot (2).
Green plants are important in the ecosystem because they are
Answer: B (producers)
Green plants make food by photosynthesis, so they are the producers on which all other organisms depend.
An anemometer is an instrument for measuring
Answer: C (wind speed)
An anemometer has spinning cups that measure wind speed.
Which of the following is NOT regarded as a pollutant on land or in the air?
Answer: E (Nitrogen.)
Nitrogen gas makes up about 78% of normal air and is harmless. Smoke, noise, sulphur dioxide and carbon monoxide are pollutants.
Which of the following groups of factors is completely abiotic?
Answer: C (Wind, altitude, humidity, light.)
Abiotic factors are non-living. Option C contains no living thing; the others include plankton, insects, conifers or bacteria.
Which of the following lists of diseases, their causes and transmission is CORRECT?
Answer: D (Smallpox, virus, skin with blister, close contact with infected person)
Smallpox is caused by a virus, causes blisters on the skin and spreads by close contact. Cholera and syphilis are bacterial, malaria spreads by mosquitoes, and sleeping sickness is caused by a protozoan.
Erosion can be reduced along a slope by
Answer: A (ridging across slope)
Ridges made across the slope (contour ridging) slow down running water and hold the soil in place.
If a handful of soil is shaken with water and left to settle, the soil particles will settle from light to heavy particles as follows
Answer: A (humus, clay, silt, sand, stones)
Heavier particles sink first, so from lightest to heaviest the order is humus (floats on top), clay, silt, sand and then stones.
Denitrifying bacteria in nature liberate gaseous nitrogen directly from
Answer: B (soil nitrates)
Denitrifying bacteria break down nitrates in the soil and release nitrogen gas into the air.
Leaching is
Answer: E (washing out of chalk and limestone from upper layers of soil by heavy rains.)
Leaching happens when rain water sinks through the soil and dissolves soluble minerals (e.g. chalk and lime), carrying them down out of the topsoil where roots can reach them.
The process of soil erosion is usually from
Answer: D (sheet → rill → gully)
Running water first removes a thin layer evenly (sheet erosion), then cuts small channels (rills), which grow into deep gullies.