WAEC Biology 2021 past questions and answers

Which of the following organelles is common to both plant and animal cells?

1. A.Cellulose cell wall
2. B.Chlorophyll
3. C.Cell membrane
4. D.Large vacuole

The diagrams are illustrations of different sections of a particular fruit.
The sections in X and Y respectively, are

1. A.longitudinal and transverse.
2. B.transverse and longitudinal.
3. C.cross and transverse.
4. D.transverse and cross.

The diagrams are illustrations of different sections of a particular fruit.
The fruit that has the illustrated sections is a

1. A.hesperidium.
2. B.capsule.
3. C.drupe.
4. D.cypsela.

The diagram is an illustration of a fungus.
The structure labelled I is associated with

1. A.sexual reproduction.
2. B.asexual reproduction.
3. C.bud formation.
4. D.gamete formation.

The diagram is an illustration of a fungus.
The structure labelled II is the

1. A.spore.
2. B.stolon.
3. C.columella.
4. D.sporangium.

The diagram is an illustration of a fungus.
Which of the following statements about the structure labelled III is correct? It

1. A.secretes digestive enzymes into the substrate
2. B.absorbs mineral salts from the soil
3. C.forms the root hairs of the organism
4. D.develops into stolon

The diagram is an illustration of a living organism.
The level of organization of the organism is

1. A.tissue.
2. B.cell.
3. C.organ.
4. D.system.

The diagram is an illustration of a living organism.
The organism belongs to the Phylum

1. A.Rhizopoda.
2. B.Ciliophora.
3. C.Euglenophyta.
4. D.Rhodophyta.

A plant cell placed in a solution with a higher water potential will

1. A.expand and then shrink.
2. B.enlarge and become turgid.
3. C.expand and then burst.
4. D.decrease in size and become flaccid.

Offspring formed by sexual reproduction exhibit more variation than those formed by asexual reproduction because

1. A.greater amount of DNA is involved in sexual reproduction.
2. B.gametes of parents have different genetic composition.
3. C.genetic materials come from parents of two different species.
4. D.sexual reproduction is a lengthy process.

Radius and ulna are bones of the

1. A.pectoral girdle.
2. B.upper arm.
3. C.pelvic girdle.
4. D.lower arm.

The diagram is an illustration of the longitudinal section of a mammalian organ.
Which of the labelled parts is the cortex?

1. A.I
2. B.II
3. C.III
4. D.IV

The diagram is an illustration of the longitudinal section of a mammalian organ.
What is the main function of the organ?

1. A.Excretion
2. B.Respiration
3. C.Reproduction
4. D.Locomotion

Detoxification of urea takes place in the

1. A.pancreas.
2. B.heart.
3. C.liver.
4. D.testes.

Which of the following hormones is suddenly secreted into the bloodstream of a frightened person?

1. A.Insulin
2. B.Adrenaline
3. C.Thyroxine
4. D.Parathormone

The temperature control centre in mammals is located in the

1. A.skin.
2. B.hypothalamus.
3. C.pituitary gland.
4. D.adrenal gland.

How many gametes are produced in the pollen grain of a flowering plant before fertilization?

1. A.One
2. B.Two
3. C.Three
4. D.Four

Which of the following organisms does not undergo incomplete metamorphosis?

1. A.Locust
2. B.Grasshopper
3. C.Butterfly
4. D.Cockroach

An enzyme reaction may begin to decline when

1. A.the optimum temperature is attained.
2. B.the pH of the medium is altered.
3. C.there is an increase in substrate concentration.
4. D.the atmospheric pressure is altered.

The diagram is an illustration of the growth of a plant in a water culture. After a few days, the solution turned green and the plant died.
What precaution should have been taken to prevent the solution from turning green?

1. A.Use a non-green plant for the experiment
2. B.Aerate the solution daily
3. C.Cover the culture vessel with opaque paper
4. D.Keep cotton wool around the seedling to make it dry.

The diagram is an illustration of the growth of a plant in a water culture. After a few days, the solution turned green and the plant died.
The death of the plant was likely caused by

1. A.excess supply of nutrients to the plant.
2. B.inadequate supply of water to the plant.
3. C.algal growth in the solution that used up the nutrients.
4. D.inability of the plant to make food due to lack of sunlight.

Which of the following factors is not necessary for photosynthesis?

1. A.Water
2. B.Carbon (IV) oxide
3. C.Wind
4. D.Sunlight

Autotrophic nutrition is a process whereby an organism obtains food

1. A.by utilizing its stored energy.
2. B.by synthesizing simple substances using energy.
3. C.from other organisms in exchange for some products.
4. D.in a synthesized form, from other living organisms.

The process that takes place at the light stage of photosynthesis is

1. A.Splitting of water molecules to form hydrogen ions.
2. B.reduction of carbon (IV) oxide to form carbohydrate.
3. C.formation of two molecules of phosphoglyceric acid.
4. D.breaking down of ATP molecules to produce energy.

The diagram is an illustration of the foot of an animal.
The adaptation of this type of foot is that it is

1. A.used as a bait to catch fish in water.
2. B.used as a paddle for swimming.
3. C.effective in scratching the soil for food.
4. D.used for killing prey in water.

The following organisms are examples of carnivorous plants except

1. A.Gloriosa
2. B.Venus flytrap
3. C.Pitcher plant
4. D.Utricularia

Plants and animals of an ecosystem make up a

1. A.habitat.
2. B.succession.
3. C.community.
4. D.population.

The illustration below is a food chain. Grass → grasshopper → domestic fowl → hawk
What would happen if the population of domestic fowl decreases? The population of

1. A.grasshoppers would decrease
2. B.hawks would increase
3. C.grasshoppers would increase
4. D.grasses available to grasshoppers would increase.

Which of the following features is a characteristic of aquatic plants? Possession of

1. A.multiple epidermis
2. B.heavily lignified tissue
3. C.finely divided leaves
4. D.succulent stem

When a large number of organisms share limited resources, the result is

1. A.mutualism.
2. B.extinction.
3. C.commensalism.
4. D.competition.

Which of the following behaviours is correctly matched with the corresponding diseases?
A. Smoking cigarette — liver cirrhosis, lung cancer, AIDS
B. Having multiple sexual partners — liver cirrhosis, syphilis, AIDS
C. Living near dirty gutter — lung cancer, syphilis, river blindness
D. Eating uncooked meat — dysentery, cholera, food poisoning

1. A.A
2. B.B
3. C.C
4. D.D

Endangered species are organisms that are

1. A.likely to migrate to other favourable lands.
2. B.likely to disappear from the surface of the earth.
3. C.reproducing profusely in an area.
4. D.dangerous to humans and attacking other animals.

Which of the following practices is a wildlife conservation method?

1. A.Use of cover crops
2. B.Crop rotation
3. C.Mulching
4. D.Discouraging poaching.

Which of the following resources cannot be conserved?

1. A.Forest
2. B.Water
3. C.Soil
4. D.Garbage

The diagrams are illustrations of types of comb found in domestic fowl.
The types of comb show

1. A.variation.
2. B.inheritance.
3. C.cell theory.
4. D.courtship behaviour.

The diagrams are illustrations of types of comb found in domestic fowl.
Which factor is most likely responsible for the various types of comb?

1. A.Environment
2. B.Genetics
3. C.Physiology
4. D.Morphology

Which of the following statements about mitosis is not correct?

1. A.Chiasmata are not formed
2. B.Bi-valents are not formed
3. C.It does not lead to variation
4. D.Four daughter cells are produced

A mixture of blood with antigen A and blood containing antibody a will

1. A.lead to agglutination.
2. B.facilitate dissolution of clot.
3. C.have no effect on blood composition.
4. D.change the blood group.

Plants suitable for experiments in genetics must not

1. A.produce numerous seeds within a short time.
2. B.have a small number of chromosomes.
3. C.have a relatively short life cycle.
4. D.produce one generation in a long period.

Which of the following statements about sickle cell anaemia is correct?

1. A.It is caused by sex-linked genes
2. B.It is more common in males than in females
3. C.Two sickle cell carrier parents may have a sickling child
4. D.It is caused by recessive genes

In humans, pointed eyebrows (B) is a dominant trait over smooth eyebrows (b). A student and the mother have smooth eyebrows while the father has pointed eyebrows. What is the genotype of the father?

1. A.BB
2. B.Bb
3. C.bb
4. D.BBbb

A woman with Rhesus negative blood group was advised not to marry a man with Rhesus positive blood group because

1. A.it will hinder her from having blood transfusion from her husband.
2. B.it will result in sickness and probably death of the offspring.
3. C.her children may all resemble her husband.
4. D.it may affect her childbearing ability.

Which of the following statements is not Lamarck's postulate on evolution?

1. A.Great changes in the environment result in corresponding changes in species
2. B.Frequently used organs become well developed while the ones not used become vestigial
3. C.Well developed acquired characters are inheritable
4. D.Survivors in a competitive community must have inherited useful traits

A sample of human blood was put in a test tube and allowed to spin in a centrifuge. The components of the blood sample were clearly separated.
(a) List the four main components of blood that would be in the test tube.
(b) Name the component of the blood that: (i) would form the top layer in the test tube; (ii) destroys pathogens; (iii) is biconcave in shape; (iv) would be relatively low in a haemophilic condition; (v) is produced in the bone marrow; (vi) is a thrombocyte; (vii) is nucleated.
(c) Mention three chemical substances transported by the blood component named in 1(b)(i).
(d) List four diseases associated with blood.
(e) Explain briefly why a disease of the blood could be dangerous.

(a) What is dentition in animals?
(b) Describe briefly the generalised structure of a tooth in animals.
(c) List three food substances that plants manufacture from glucose.
(d) Make a diagram, 6 cm to 8 cm long of an experimental set-up to show that oxygen is produced during photosynthesis.

(a) Complete the table below by placing each of the following organisms under the appropriate heading:
Algae, Bacteria, Dog, Water lettuce, Tadpole, Cat, Lemna, Waterleaf, Mucor, Mushroom
Headings: Decomposer | Producer | Consumer
(b)(i) Name four products of decomposition. (ii) Mention three roles of decomposers on a refuse dump.
(c) List three materials found in a refuse dump which would not be affected by the action of decomposers.

(a) Complete the table below by naming five wildlife animals in West Africa and one body part each that makes them endangered because of the activities of humans.
Headings: Animal | One body part that makes animal endangered
(b) State three effects each of the following factors on the conservation of natural resources: (i) Poor economy of a nation; (ii) poaching.
(c) State four roles played by the Government in conservation of natural resources.

(For candidates in Nigeria only)
(a) Complete the table below by naming the nutrient cycle that involves each of the given processes and give three other processes involved in the nutrient cycle.
Process | Nutrient cycle | Three other processes involved in the named nutrient cycle
Combustion | ________ | ________
Precipitation | ________ | ________
Lightning | ________ | ________
(b)(i) What is irritability?
(ii) Complete the table below by stating the type of response elicited by each of the given actions.
Action | Type of response
Euglena moving towards source of light | ________
Opening and closing of Mimosa plant leaves | ________
Mosquitoes avoiding repellants | ________
Earthworm moving away from light | ________
Sperm cell moving towards chemical substances of an ovum | ________
Four o'clock plant opening at 4.00 p.m. | ________
Shoot of bean seedling growing towards sunlight | ________
(c) Name three animals each that exhibit: (i) territoriality; (ii) seasonal migration; (iii) display.