WAEC GCE 2025 BIOLOGY PRACTICAL ANSWER



(1ai)
Plasmolysis

(1aii)
Water leaves the plant cell by osmosis (from higher water potential inside the cell to lower water potential in the surrounding solution) across the partially-permeable membrane. The large central vacuole loses water and shrinks, the cytoplasm and cell membrane pull away from the cell wall and the cell becomes flaccid/plasmolysed.

(1b)
I: Cell wall
II: Cell (plasma) membrane
III: Central vacuole

(1c)
Kingdom Plantae

(1cii)
(PICK ANY TWO)
(i) Presence of a rigid cell wall.
(ii) Presence of a large central vacuole.
(iii) Regular or rectangular plant cell shape.
(iv) Presence of chloroplasts.
(v) The cell wall is made of cellulose, a plant feature.
(vi) The cell can become turgid or plasmolysed due to osmosis.

(1d)
(i) Turgid: C, D
(ii) Flaccid: E
(iii) Plasmolysed: F, G
(iv) Unchanged: E

(1e)
Check the image below

(1fi)
Osmosis is the movement of water molecules from a region of higher water concentration to a region of lower water concentration through a partially permeable membrane.

(1fii)
(PICK ANY THREE)
(i) It helps root hairs absorb water from the soil.
(ii) It helps plants stand firm by maintaining turgor pressure.
(iii) It enables growth and enlargement of plant cells.
(iv) It helps in opening and closing of stomata.
(v) It aids the transport of nutrients and minerals dissolved in water.
(vi) It prevents wilting by keeping plant tissues moist and firm.

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(2a)
I: Funnel
II: Collecting jar / bottle
III: Light / lamp
IV: Stand / base
V: Wind vane arrow
VI: String / cord
VII: Net rim / hoop
VIII: Net handle

(2b)
Check the image below

(2c)
T: The beating tray is placed under a plant or tree branch and the branch is shaken or beaten so that insects fall into the tray for collection and study.

W: The sweep/dip net is moved through grasses or water to catch insects or small aquatic animals, which are then removed for observation

(2d)
(PICK ANY ONE)
(i) Ensure the collecting bottle is tightly fixed so insects cannot escape.
(ii) Keep the light trap away from rain or water to prevent damage.
(iii) Do not touch the electrical parts with wet hands to avoid electric shock.
(iv) Place the trap in a stable position so it will not fall or break.

(2e)
(i) dip/sweep net: used to collect small aquatic animals.
(ii) thermometer: used to measure water temperature.

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(3ai)
Germination

(3aii)
(i)Water
(ii) Oxygen
(iii)Suitable temperature

(3b)
(i) A: Epigeal germination
(ii) B: Hypogeal germination

(3c)
A:
(i) Cotyledons are pushed above the soil.
(ii) Shoot (plumule) elongates to lift cotyledons out of the ground.

B:
(i) Cotyledons remain below the soil.
(ii)Plumule grows upwards while cotyledons stay underground.


(3d)
I: Cotyledon
II: Plumule
III: First foliage leaf
IV: Second foliage leaf
V: Third foliage leaf
VI: Stem
VII: Primary root
VIII: Secondary root
IX: Plumule
X: Radicle

(3ei)
[TABULATE]
A:
(i) Cotyledons above the soil.
(ii) Larger cotyledons.
(iii) Germination type is epigeal.

B:
(i) Cotyledons remain below the soil.
(ii) Smaller cotyledons.
(iii) Germination type is hypogeal.

(3eii)
(i) Both undergo germination process.
(ii) Both develop roots and shoots.
(iii) Both require the same essential conditions

(3f)
From stage 1, the seed absorbs water and the radicle emerges to form the primary root. By stage 2, the shoot begins to grow upwards while roots expand downward. In stage 3, the plumule (young shoot) penetrates the soil surface, and roots continue developing. By stage 4, the seedling has leaves, an established root system, and cotyledons remain below the soil.

(3g)
[TABULATE]
Plant A (Epigeal germination): Beans, Tomato

Plant B (Hypogeal germination): Coconut, Maize, Rice

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WAEC GCE 2025 BIOLOGY THEORY & OBJ ANSWER

BIOLOGY OBJECTIVE ANSWERS
Pls kindly trace it from your system. The options are being reshuffled. You might see number 1 as any number, so trace and be fast. You might also see option A as option C, B or D. Just use the answers in words and and trace properly. Kindly Trace it carefully to avoid errors!!!!


1. The correct answer is A. petiole.
2. The correct answer is A. Osmosis.
3. The correct answer is B. Osmosis.
4. The correct answer is C. Increase in food and energy needs.
5. The correct answer is C. centriole, formation of spindle fibers.
6. The correct sequence is: A. spiracle, trachea, tracheole, body fluid.
7. The answer is: A. P, Q
8. The answer is: B. is lost during transformation.
9. The answer is: D. arrangement of chromosomes at the equator.
10. The answer is: D. xylem.
11. The answer is: C. hepatic portal vein and inferior vena cava.
12. The answer is: C. capillaries.
13. The answer is: A. raker.
14. The answer is: D. III is forklike to sieve debris from entering the fish.
15. B insufficient secretion of thyroxine
16. B coloration of the sclera
17. A they are transported through the blood
18. A axile
19. D berry
20. D an achene
21. A fixation of carbon (IV) oxide
22. C nitrogen
23. D lymph in the lacteal
24. B the PH of the medium is altered
25. C colon
26. C molar crushes food
27. C. sea.
28. B. I and III.
29. C. II and IV.
30. A. Chemosynthesis in organisms
31. B. sunlight.
32. D. ensures a greater chance of survival
33. B. carbon cycle.
34. A. industrial chimneys, combustion and effluents.
35. C. An evergreen climax forest
36. D. kill most strains of bacteria.
37. A. conserving the soil by reducing erosion.
48. The correct answer is B. structural.
49. The correct answer is D. protection.
50. The correct answer is B. inheritance of acquired characteristics.



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(1a)
A conditioned reflex is a learned response to a stimulus that is developed through association with an unconditioned stimulus.

(1aii)
(i)Enables animals to learn and adapt to their environment.
(ii)Helps animals associate stimuli with food or danger.
(iii)Enhances survival through learned responses to specific stimuli.

(1b)
(i)Sensory neurones
(ii)Motor neurones
(iii)Interneurones

(1ci)
(i)Blinking when dust enters the eye
(ii)Withdrawal of hand from a hot surface
(iii)Sneezing
(iv)Knee jerk reflex

(1cii)
(i)Measuring the length of a specimen
(ii)Recording observations
(iii)Handling laboratory equipment
(iv)Following instructions from the teacher

(1d) TABULATE
Hormonal coordination
(i) Generally slower, long lasting effects
(ii) Uses chemical messengers ( hormones ) carried by blood
(iii) Effects are widespread and diffuse

Nervous coordination
(i) Very rapid, short - lived effects
(ii) Uses electrical impulses via neurons
(iii) Effects are precise and localized

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(2&3)


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(4ai)
Mutation plays a role in evolution by introducing genetic variation, providing new traits that can be acted upon by natural selection, potentially leading to the emergence of new species.

(4aii)
(i)Fossil record
(ii)Comparative anatomy
(iii)Molecular biology (e.g., DNA and protein sequence similarities)

(4bi)
under Two scientists:
(i)Charles Darwin
(ii)Alfred Russel Wallace

(4bii)
Under Famous theory of evolution:
Theory of Natural Selection (by Charles Darwin)

(4c)
(i) Spirogyra, Moss, Fern, Conifer, Maize

(ii) Tilapia, Toad, Lizard, Monkey, Human

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(5a)
Courtship behaviour is the set of actions or displays carried out by animals to attract a mate and prepare for reproduction. These behaviours increase the likelihood of successful mating and often involve visual displays, vocalizations, or chemical signals.

(5aii)
(i) elaborate dances
(ii) vocalizations
(iii) physical contests.


(5bi)
[TABULATE]

=Complete metamorphosis=
(i) Involves four distinct stages: egg, larva, pupa, and adult.
(ii) The larval stage looks completely different from the adult

=Incomplete metamorphosis=
(i) Involves three stages: egg, nymph, and adult
(ii) The nymph stage resembles a smaller, wingless version of the adult.

(5bii)
(i) Complete metamorphosis: Butterflies and beetles

(ii) Incomplete metamorphosis: Grasshoppers and cockroaches

(5ci)
(a) Food
(b) Water
(c) Shelter/Space
(d) Mates

(5cii)
(a) Atmospheric carbon dioxide
(b) Respiration of organisms
(c) Decomposition of organic matter
(d) Combustion of fossil fuels

(5d)
[TABULATE]

=THREE AGRICULTURAL ACTIVITIES=
(i) Deforestation
(ii) Excessive use of fertilizers
(iii) Overgrazing

=TWO ADVERSE EFFECTS EACH OF THE AGRICULTURAL ACTIVITY ON THE ECOSYSTEM=
(i) (a) Habitat loss
(b) Soil erosion

(ii) (a) Eutrophication of water bodies
(b) Soil acidification

(iii) (a) Desertification
(b) Loss of vegetation cover


(5e)
(i) Nutrient and oxygen supply to the fetus
(ii) Waste removal from the fetus