Quiz 9 of 9

2021 Biology NECO Theory Past Questions

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2021 Biology NECO Theory Question 1

ANSWERS

(1) (a) – To search for food.

– To escape from danger, natural disaster, or predators.

– To search for a mating partner or for breeding purposes.

– To search for shelter

– To escape harsh climatic changes

– Seasonal migration

(b) Phloem: It transports manufactured food from the leaves to other parts of the plant.

Leaf: The chlorophyll of the leaf traps radiate energy from sunlight for photosynthesis

  • For transpiration
  • For guttation
  • For water conservation
  • For food storage
  • For vegetative propagation

Xylem: Conducts water and mineral salts from the roots to other parts of plant.

  • Provides mechanical support in plants.

Flower: Its bright colour attracts insects, birds for pollination

  • For reproduction
  • Formation of male and female gametes
  • Fertilization resulting in the formation of fruit.

(c)  – They have a well developed root system to hold them to the soil.

– They have well developed extensive root system to absorb water.

– Presence of a large amount of strengthening tissue/xylem for support.

– Presence of sunken stomata to reduce transpiration

– They possess chlorophyllous/green stems which photosynthesize.

– They possess swollen stem leaves that act as storage organs

– Presence of thick, waxy cuticles which reduces the rate of transpiration.

– Their leaves are small, needle-like/spine to reduce water loss.

– They have reduced number of stomata to prevent water loss.

– They possess multiple epidermal layers for water conservation.

(d) (i) Light rays from an object enter the eye. It passes through the cornea, aqueous humour, lens and vitreous humour.

  • The rays are refracted and brought to focus on the retina.
  • The stimulus of the reflected light is received by rods and cones depending on the light intensity which converts the stimulus to impulses.
  • The impulse is transmitted through the optic nerve to the optic lobe of the brain which correctly interprets the image.

(ii)     – Evidence from vestigial organs

– Evidence from geology or fossil

– Evidence from comparative anatomy

– Evidence from physiology/biochemistry

– Evidence from taxonomy

– Evidence from comparative embryology

2021 Biology NECO Theory Question 2

ANSWERS

(2) (a) – Eyelid

– Eye lashes

– Eye socket

– Conjunctiva

(b) Excretion: This is defined as the removal or elimination of waste products/harmful by-products of metabolism from the body of an organism.

Competition:  It is the interaction or struggle between members of the same species/population/two or more species occupying the same tropical level to obtain mutually needed resources that are in short supply in the habitat.

Deforestation: Deforestation is defined as the deliberate, intentional or indiscriminate clearing of forest areas/trees through human activities.

(c) Thoracic Vertebra Diagram of a Rabbit  

(d)    – Salting

– Freezing/refrigeration

– Drying/sun drying

– Smoking

– Chemical preservation

– Canning

– Pasteurization

– Fermentation

– irradiation

2021 Biology NECO Theory Question 3

ANSWERS

(3) (a)  – Meiosis is four (4)

– Mitosis is two (2)

(b) (i) – It permits genetic variability of individuals

– It allows production of hybrids of desirable traits/characters.

– It enhances formation of new species

– It allows for continuity of the species

– It maintains the chromosome numbers from one generation to the other

– The species can adapt to new environments due to variation which gives them a survival advantage.

– More resistant to diseases

(ii) A remora fish would attach itself to a shark. A remora fish would use the shark for transportation. The remora fish gets its food from the shark; the shark gets no benefits from the remora fish. The relationship between them is commensalism.

(c) (i) – Headache

– Dry cough

– Tiredness/fatigue

– Aches and pain

– Sore throat

– Loss of taste or smell

– Difficulty in breathing

– Chest pain

– Vomiting

– Diarrhoea

(ii) It removes blood from the kidney.

(d) Ecological Niche: The interaction of a species with the other members of the same community. It is the specific part of a habitat occupied by a particular organism.

In a niche, every organism is adapted to play a specific role in the community. No two organisms share the same role at the same time, hence no competition between them.

Population Density: It refers to the number of individuals present per unit area at a given time. The number of individuals present is represented as N and A, area in square kilometer (Km represented as (S) thus

Population density is measured in the following ways:

  • Total count method
  • Relative density
  • Indirect estimation
  • Biomass estimation

Climax Community: This is an ecological community in which populations of plants or animal remains stable and exist in balance with each other and their environment.

It is the final stage of succession. Climax community is determined by the climate of the region. The climax community is called a biome.

2021 Biology NECO Theory Question 4

ANSWERS

(4) (a) (i) It is a prolonged dormancy or inactivity of some animals during a hot or dry period. It is characterized by lowered metabolic rate. The purpose is to avoid damage from high temperatures and the risk of desiccation.

(ii) – Ears: Sensory system for hearing/balancing

– Eyes: Sensory system for vision/sight

– Tongue: Sensory system for taste

– Nose: Sensory system for smell

– Skin: Sensory system for touch.

(iii) The three semi-circular canals in the ear are sensitive to movement of the head. They are filled with endolymph. The ampulla in the semi-circular canals contains sensory hairs. When someone moves his head, the ampulla moves in the endolymph. It pulls on the hair, so the hair sends messages through the auditory nerve to the brain.

(b) (i) Neuron: It transmits impulses to and from the brain.

(ii) Cerebrum:  The cerebral cortex serves as the centre for memory and thinking.

  • It controls voluntary actions such as hearing, smelling, seeing, and touching.
  • It helps in the regulation and coordination of nerve impulses.

(iii) Medulla Oblongata: It controls many involuntary actions associated with heartbeat, digestion, and respiration.

  • It regulates blood pressure by controlling the constriction and dilation of blood vessels.
  • It serves as a reflex centre for vomiting, coughing, sneezing, and swallowing.

(iv) Cerebellum:

  • It coordinates voluntary movements
  • For muscle coordination and postures
  • It is important for learning and motor behaviours.

(c) (i)

(c) (ii)  – It contains chlorophyll to absorb light.

– Presence of stomata to allow diffusion of carbon-dioxide.

– Network of tubes (xylem and phloem) to transport water (xylem) and food (phloem).

– Flat shape to receive maximum sunlight energy.

– Presence of guard cells to regulate opening and closing of stomata.

– Presence of a large network of veins to support the leaf and transport water and mineral ions and sucrose (sugar).

2021 Biology NECO Theory Question 5

ANSWERS

(a) (i) Display in Agama Lizard

The male Agama Lizard displays its bright colours and approaches the female. The female lizard curves her back, lifts her tail vertically. The male wags its tail, nods its head, and grips her by the neck, pushes his tail under her body. Their cloaca’s come into contact for copulation to take place.

(ii) – Haemophilia (bleeding disease)

– Baldness

– Colour blindness

– Albinism

– Congenital night blindness

(iii)

(b)

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