NABTEB GCE 2025 Biology Answers – Type A

BIOLOGY OBJ (TYPE A)
01-10: BBBBCCBCCB
11-20: CBBCAACBBB
21-30: BADBBCABCA
31-40: BBCCBCBBDB
41-50: BBCDBABBCB

COMPLETED

NABTEB GCE 2025 BIOLOGY ANSWERS (TYPE A)

INSTRUCTIONS: ANSWER FOUR QUESTIONS ONLY, AT LEAST ONE QUESTION FROM EACH PART.

PART I

(1ai)
(Draw the diagram)

(1aii)
(i) Chloroplast: Chloroplast carries out photosynthesis. It traps sunlight and converts it into chemical energy for the production of glucose.
(ii) Mitochondrion: Mitochondrion carries out cellular respiration. It releases energy from food substances in the form of ATP to support cellular activities.

(1b)
(i) Cell level: This is the basic level where the cell is the smallest structural and functional unit of life capable of carrying out all life processes. Example: An amoeba exists and functions as a single, independent cell.
(ii) Tissue level: This is a level where similar cells with the same structure and function group together to perform a specific task. Example: Muscle tissue in animals or xylem tissue in plants.

(1ci)
Osmosis: Osmosis helps in the movement of water across the cell membrane, maintaining turgor pressure in plant cells, aiding absorption of water by roots, and regulating the balance of water within cells.

(1cii)
Diffusion: Diffusion enables the movement of dissolved substances such as gases, nutrients, and waste products across cell membranes, ensuring the exchange of materials between the cell and its environment.
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PART II

(2ai)
Growth is the irreversible increase in size, mass, and complexity of an organism or part of an organism over time.

(2aii)
(i) Light intensity
(ii) Water availability
(iii) Temperature
(iv) Soil nutrients
(v) Carbon dioxide concentration

(2aiii)
(i) Auxins
(ii) Gibberellins

(2bi)
Germination is the process by which a seed develops into a new plant under favorable conditions.

(2bii)
[IN A TABULAR FORM]
=HYPOGEAL GERMINATION=
(i) Cotyledons remain below the soil surface.
(ii) Epicotyl elongates to push the plumule above the soil.
(iii) Seedlings are usually more protected from environmental hazards.

=EPIGEAL GERMINATION=
(i) Cotyledons are pushed above the soil surface.
(ii) Hypocotyl elongates to lift the cotyledons.
(iii) Seedlings are more exposed but can start photosynthesis early.
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(3ai)
(i) It is required for the formation of proteins for the growth and repair of tissues.
(ii) It is used in the production of nucleic acids that carry genetic information.
(iii) It is needed for the formation of enzymes and certain hormones in organisms.

(3aii)
(i) Nitrogen fixation by bacteria in the soil: Bacteria such as Rhizobium convert atmospheric nitrogen into compounds like nitrates which plants can absorb.
(ii) Lightning and thunder activity: Lightning causes nitrogen to combine with oxygen to form nitrates which are washed into the soil for plant use.

(3b)
(Draw the diagram)

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such as the skull protecting the brain and the rib cage shielding the heart and lungs.
(iii) Movement: Bones serve as levers and points of attachment for muscles, enabling voluntary movements when muscles contract and pull on the bones.
(iv) Mineral storage and blood cell production: Bones store essential minerals like calcium and phosphorus and contain bone marrow, which produces red blood cells, white blood cells, and platelets.

(4bi)
Blood is a specialized connective tissue that circulates throughout the body, transporting oxygen, nutrients, hormones, and waste products to maintain homeostasis and support life.

(4bii)
(i) Red blood cells: Transport oxygen from the lungs to body tissues and carry carbon dioxide from tissues to the lungs for excretion.
(ii) White blood cells: Defend the body against infections by destroying pathogens and producing antibodies.
(iii) Platelets: Aid in blood clotting to prevent excessive bleeding after injury.

(iv) Plasma: A liquid medium that transports nutrients, hormones, waste products, and gases throughout the body.
(v) Proteins in plasma: Maintain osmotic pressure, aid in clotting, and serve as antibodies to fight infections.

(4c)
(i) Reduces the risk of maternal and child mortality by allowing adequate spacing between pregnancies.
(ii) Helps parents provide better care, nutrition, and education for their children.
(iii) Prevents overpopulation, reducing pressure on resources such as food, water, and housing.
(iv) Improves women’s health by preventing frequent or high-risk pregnancies.
(v) Enhances economic stability for families by allowing them to plan and allocate resources effectively.
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