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Degree for food items = 360^\circ - (120^\circ + 80^\circ + 43^\circ + 30^\circ + 18^\circ) = 360^\circ - 291^\circ = 69^\circ ∴∴ Amount spent on food items = \(\frac{69}{360}\)\times12,000.00 = N2300.00

(a) Observation after colouring the tissue by the red ink or eosin - The fing-like section is stained red. The remaining sections remain colourless (i.e others are not stained) (b) Observation after flooding with a drop of iodine for about one minute -A layer of ring-like tissue is stained blue-black or dark (c) () In (a) the tissue stained red conducts water and mineral salts (ü) In (b) the tissue stained active blue-black or black stores starch (d) Differences between the arrangements of tissues in specimen I and J I dicot Stem (i) Ring like vascular bundles (i) Presence of cambium (iii) Has wide cortex (v) Has distinct endodemis or starch sheath (v) Has distinct pith J Monocot Stem (i)Scattered vascular bundles (ii) Absence of cambium (iii) Has narrow or small cortex (iv) Has no endodermis or starch sheath (v)Has no distinct pith or has no pith

(a)The process involved in the breakdown of glucose in living cells occurs in two stages namely anaerobic and aerobic stages (i) Anaerobic process: In this process, glucose is broken down into pyruvic acid in the presence of enzyme or hexokinase by a process called glycolysis. Oxygen is absent in this process. For each of the glucose respired, two molecules of ATP are released. (ii) Aerobic process: In the mitochondria, pyruvic acid under the influence of enzymes is oxydised to Acetyl-coenzyme A (AcetylcoA) releasing carbon (iv) oxide. Acetyl COA enters the krebs cycle or citric acid cycle where series of changes take place and oxygen combines with hydrogen to form water. In the process, a large quantity of energy is generated in the form of ATP (Adenosine triphosphate). The equation for the overall process is as follows: C\(_6\)H\(_1\)\(_2\)O\(_6\) + 6O\(_2\) → 6H\(_2\)O + 6CO\(_2\) + Energy. In yeast cells, in the absence of oxygen, glucose is broken down into ethanol, carbon (iv) oxide and energy. C\(_6\)H\(_1\)\(_2\)O\(_6\) → 2C\(_2\)H\(_5\)OH + 2CO\(_2\). Energy. Strenuous exercise results in depletion of oxygen in the muscles. Hence, pyruvic acid is converted to lactic acid which can be oxidized further to yield energy. (b) Glycogen can be converted to glucose during exercise when the body needs more glucose to produce sufficient energy and when one is anxious, sick, full of fear, fasting or hungry. This results in a fall in the blood sugar level. Experiment to demonstrate that oxygen is released during Oxygen photosynthesis. Aim: To show that oxygen is released by green Test tube plant during photosynthesis. Apparatus: Two beakers, two funnels, two test tubes, water plant (Elodea). Method — Fill the beakers with Gas bubble water and place the water plant in beaker A and B. Invert a glass funnel in the beaker in order to enclose the water plant. Invert a test tube with water over the stem of the funnel. Experiment A is exposed to sunlight while B is covered with a cardboard paper or placed in the dark. Leave both experiments for sometime. Water containing Observation: Bubbles of gas appear or are noticed in experiment A. carbon IV oxide (CO2) When tested with a glowing splint, it rekindles, confirming that the Beaker gas is oxygen. This observation in A is absent in B. Conclusion: What happens in A shows that oxygen is liberated during photosynthesis.

(a) (i) Reasons why termites are called social insects: (1)They live in colonies or communities. (2)They undergo division of labour. (ii) Castes found in termites nest are -king -queen -workers -soldiers. Role: king fertilizes the eggs Queen lays the eggs workers do all the necessary work, e.g. building of colony, provision of food, feeding of the young ones and the queen Soldiers defend the colony. (b) Behavioural adaptation of termites: (i) Laying of many eggs which hatch into nymphs thereby ensuring survival of many. (ii) Movement in group enables them to ward off their enemies. (iii) They build tunnels and burrows into the heart of wood and this protects them from their enemies and harsh weather conditions. (iv) They feed on their dead members and this helps to maintain a clean and healthy colony. (v) Presence of inter-connecting tunnels enhances aeration within the termites nest.

(a)Succession can be defined as a progressive natural development of vegetation towards a climax during which one community is gradually replaced by others. The abandoned farm land is a secondary succession as a result of the fact that it follows a partial destruction of the original vegetation. The process is as follows: (i) Decay of plants and animals of the old farm enhances nutrient of the soil. (ii) The pioneer or initial colonizers are insects' eggs, larvae, worms and seeds of plants carried by animals or by wind. There are also underground stems like rhizomes and stem tubers. (iii) Next stage includes the hatching of eggs of insects, larvae development, germination and growth of herbaceous plants like grasses and lilies. (iv) Growth of vegetation attracts rodents to feed on grasses. (v) Lizards are also attracted to feed on the insects. (vi) Herbs are displaced by shrubs. (vii) Shrubs are in turn displaced by trees. (viii) Trees attract birds, monkeys and tree reptiles. (ix) Presence of herbivores, carnivores and omnivores (animal community) makes the community to develop or reach a climax. This results in a complex food web. (b) Ways by which micro-organism can be controlled to maintain good health are: (i) People should be vaccinated against killer diseases. (ii) There should be personal hygiene, e.g. regular cleanliness of our body, environment, teeth and clothes. (iii) Avoid overcrowding to prevent infectious diseases, e.g. tuberculosis. (iv) Destroy breeding ground for mosquitoes. (v) Isolate people with highly infectious diseases, e.g. leprosy (vi) Promote health education (vii) Cover food to prevent contamination by rats, flies, cockroaches, etc. (viii) Encourage ventilation of houses. (ix) Cut bushes around the house and drain stagnant water properly.

(a)Process of meiotic division: (i) In the prophase of first meiotic division, there is formation of chiasma. Variation occurs from the number and position of chiasmata formed. This determines the different combination that is possible in genes relative to the sequence of genes on the chromosomes. (ii) In the metaphase of the first meiotic division, segregation of chromosomes occurs. This results in mixing of genes from different individuals carried on different chromosomes which now result in variation between parents and offsprings or among offsprings. Mixing of genes is known as crossing over. (b)(1)Mendel's first law called law of segregation of genes states that characters of an organism are controlled by genes occurring in pairs which are independently transmitted in gametes from one generation to another without undergoing any alteration. (ii) The second law known as independent assortment of genes states that character behaves as a separate unit and is inherited independent of another character.

(a) The stigma and anthers mature at different times (i) Male and female parts of the flower are located on different plants (ii) Male and female flowers occur separately on the same plant (b) Petals are dull with no nectar of scent. Pollen grains are numerous, light, smooth and powdery so that they can be blown by the wind.

2. (a) Sclerenchyma, Collenchyma (b) Synthesis of carbohydrates and proteins. It is a protein collecting and station.

(a) 1- endosperm Il - the cotyledon ll - coleoptile IV - the coleorhiza (b) I and l - endosperm and cotyledon.

Yeast, Hydra.

(a) I-The olfactory lobe I| - the cerebrum ll - the cerebellum IV - the medulla oblongata V- spinal nerve (b) V- spinal nerve

The process of chemosynthesis.

(i) Guinea worm disease (ii) Damping off of seedlings.

(i) Availability of food (ii) Competition (iii) Increased rate of mortality.

(i) Secretion of enzyme for extracallular digestion of food (ii) Possession of rhzoids for absorption of nutrient