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(a)(1) Producer: This is a green plant or autotroph which traps the energy of sunlight, radiant energy or solar energy and converts it to chemical energy in order to form organic compounds and photosynthesis using CO2 and water or simple inorganic substances as raw materials. It forms the starting point or origin of every food chain. (ii) Consumer: This is an organism which derives its nutrients, energy and food from eating plants directly or indirectly. In other words, it is an organism which depends on other organisms for food, energy and nutrients. All consumers are heterotrophs and they lack chlorophyll. They are either animals that derive their nutrients, food and energy from eating plants directly (e.g. cow and sheep) and are called herbivores or primary consumers or they are other animals (e.g. cats, hyenas, lions and leopards) that eat herbivores and thus derive energy indirectly from the producers. These are called carnivores or secondary consumers. (iii) Community: This refers to a group of plants and animals that occupy a given area and are adaptable to the conditions of their environment. They are interdependent i.e depend on one another and can continue to live successfully and reproduce new offspring. (iv) Decomposer: Decomposers are fungus or bacteria which lives saprophytically or feed on dead remains of plants, animals and organisms leading to or resulting in recycling of nutrients by breaking down organic matters to produce soluble nutrients which are absorbed by plants. (b)(i) Characteristics of trees in Tropical Rain Forest: (a) The trees are predominantly woody. (b) They are stratified. (c) Some are called "emergents, ' and attain a height of over 60 metres. (d) They have straight columnar trunks with branches only at the crown. (e) They have buttresses. (f) They have thin smooth barks without conspicuous fissures or lenticels. (g) They usually have dark green leaves that are broad,large and leathery. (h) The leaves are with entire margin, having drip tips or extended tips. (i) The trees form canopies at the crown and cast dense shade on the underneath. (j) They have cauliflory or flowers attached directly to trunks and branches - not on inflorescence stalks. (k) Some of the trees have stilt roots. (ii) Characteristics of trees and shrubs of the Savanna: (a) The trees and shrubs are scattered and woody. (b) They have narrow leaves and few stomata. (c) Their leaves have thick cuticle. (d) The trees are not usually very tall (10-50 metres). (e) They have gnarled, twisted or crooked trunks with fissured, fire-resistant or corky barks (g) Most of the trees are deciduous, they shed leaves during dry season. (h) They also have long taproot with extensive root system.

No expanded working has been attached for this question yet. The verified answer is Option E.

(a)(i) Parasitism; is a feeding relationship or association between two organisms, in which the parasite lives in or on the body of the host, deriving benefit from and causing harm to it while the host loses in the process. (ii) Commensalism; is a relationship or an association between two organisms of different species, in which one, the commensal benefits or gains while the other, the host, is not adversely or significantly affected in any way, i.e., it is not harmed, neither loses gains. (b)(i)Fungal parasites of host plants include; (a) Ustilago on maize (b) Puccinia on maize,wheat or barley (c) Phytophthora palmivora on cocoa (d) Phytophthora infestans on tomato/potato (e) Alternario on tomato. (ii) Bacterial parasites of humans include; (a) Clostridium tetani - (tetanus;) (b) Neisseria - (Gonorrhaea;) (c) Mycobacterium - (Tuberculosis and leprosy;) (d) Vibrio cholerae -(Cholera;) (e) Salmonella paratyphi typhi (typhoid) (f) Escherichia coli (dysentery). (c)(i) Symptoms of malaria are; (a) high fever or high temperature (b) loss of appetite (c) pains at the joints (d) headache (f) rigour or shivering (g) stomach cramps (h) dizziness (i) vomiting co weakness or tiredness. (ii) To control malaria (a) treat the patient with curative drugs, e.g. chloroquin, cannoquin (b) use anti-malaria drugs (c) prophylactic drugs, e.g. daraprim (d) sleep under mosquito net (e) use screen wire net houses, windows and doors against mosquitoes to apply mosquito repellent balms (g) burn mosquito coils or spray room with insecticides (h) drain or avoid stagnant water bodies, bury or recycle empty cans (i) burn herbs or plant materials, e.g. lemon grass. (j) spray stagnant water with oil (k) clear the bushes around the house by using predators, e.g. introducing fish to eat up mosquito larvae. (m) educate or enlighten the public or community on the control of mosquito

(a) A receptor; is a sensory cell which receives stimuli, initiates and transmits an impulse through neurons to the brain, spinal cord or the central nervous system. (b) General features common to all receptors: Generally, receptors consist of a group of sensory cells with their free surfaces bearing, short hair-like processes otherwise called dendrites. Around their basal portions are nerve fibres which lead to the spinal or cranial nerves and the central nervous system. (c) Diagram showing the outer/external and middle ear of human. (ii) How to care for the ear: (i) avoid inserting sharp objects into the ear (ii) clean regularly with cotton buds (iii) report any ear discharge or problem to the medical doctor (iv) avoid places of loud noise (v) avoid misuse of ear-phones (vi) avoid introducing hot liquid into the ear (vii) treat measles and meningitis instantly to prevent deafness (viii) avoid using quinine carelessly

(a) The main constituents of the mammalian blood are: (i)Plasma/fluid matrix (ii) Erythrocytes/red blood corpucles (iii) Platelets/thrombocytes (iv) Leucocytes/white blood cells or white corpuscles. (b) Blood Constituents and their functions; (i) Plasma: (a) plasma transports end products of digestion or digested food especially glucose and amino acids. (b) It transports waste products, hormones, heat from very actively respiring tissues, CO2, urea or waste materials, antibodies, amino acids and mineral salts. (c) It participates in blood clotting. (d) It transports oxygen. Arteries Veins 1.They carry blood away from the heart. 2. Blood flows rapidly under high pressure. 3. They possess narrow lumen. 4. Walls have thick layer of muscles i:e. they are thick-walled. 5. They have elastic walls. 6. Valves are absent. 7. They start as large vessels and subsequently sub-divide. 8. They are deep-seated in the body. 9. Blood flows in arteries under the pressure from the heart beats or pulse. 10. Arterial blood is bright red. 11. All arteries carry oxygenated blood except the pulmonary artery. They carry blood into the heart. Blood flows gently or slowly under low pressure. They possess wide lumen. They are thin-walled. The walls are inelastic. Valves are present. They start as tiny vessels and subsequently unite or merge into large vessels They are superficially-seated in the body i.e., not deep seated Blood flows in veins with assistance from contracting muscles and gravity and are not detectable. Venous blood is dark or dull red. . All veins carry deoxygenated blood except the pulmonary the pulmonary vei (ii) Erythrocytes (Red blood cells): (a) The red blood cells transport oxygen as oxyhaemoglobin. (b) They transport small quantities of CO2 and (c) They take part in blood clotting. (iii)Leucocytes (White Blood Cells): (a) Leucocytes defend the body against disease - causing organisms, for example, phagocytes engulf or ingest and breakdown disease-causing bacteria. (b) They produce antibodies or immunity for the body. (iv) Platelets: They aid clotting of blood.

(a) Sexual reproduction is the fusion or joining of male and female gametes or nuclei from different individual to form a zygote which later develops into an embryo or organism. (b) Functions of the placenta: (i) The placenta attaches the foetus to the uterine wall of the mother. (ii) It filters out urea or nitrogenous waste of baby's blood and transfers it to the.mother's blood and kidneys. (iii) It absorbs digested food from the mother's blood and passes it on to foetus by diffusion. (iv) The placenta allows passage of ingredients or antibodies that protect the developing foetus against infection. (v) It exchanges CO from the foetus' blood for oxygen from the mother's blood. (vi) It prevents the mixing of foetal-and mother's blood. (vii) The placenta produces the hormones that prevent ovulation and menstruation during pregnancy. (viii) It prevents passage of some pathogens from mother to foetus. (ix) It converts glucose to fructose. (x) It allows the passage of drugs or vaccines and alcohol from mother to foetus. Functions of the umbilical cord: (i) The umbilical cord attaches the foetus to the placenta. (ii) The vein in the umbilical cord transports digested food and oxygenated blood from the placenta to the foetus. (iii) The artery transports waste metabolic products or excretory products and deoxygenated blood from the foetus to the placenta (vii) It suspends foetus in the amniotic cavity. (c) Types of placentation in flowering plants: (i) Axile (tomato) (ii) Marginal (legumes) (iii) Parietal (pawpaw) (iv) Free-central (orange) (v) Basal (vi) Central (vii) Pendulous (viii) Superficial (d) The conditions necessary for seed germination include; (i) viability of seed (ii) adequate supply cif moisture or water (iii) suitable temperature i.e warmth (iv) adequate supply of air e.g. oxygen (v) suitable soil pH.

(a)(i) Ecological succession; is the orderly series of changes occurring in plant and animal or microbial communities over a period of time, resulting in the establishment of a final,stable and climax community. (ii) Characteristics of ecological succession of plants:. (a) Ecological succession- of plants takes place in a newly formed open habitat barren area or land. (b) Successional changes are orderly and they develop in a certain sequence. (c) Pioneer or earliest colonisers are hardy with short life cycle and are replaced by small herbaceous plants (d) The rate of successional change is rapid initially but, gradually, it slows down until the final climax or stable community is reached. (e) The number of serial communities depends on minor differences in edaphic, topographic or other local conditions. (f) Succession occurs over a period of time. (g) The earliest colonizers are usually very few species. (h) During their life, the pioneers make extensive use of the material in their environment to a point of depletion. (i) Death of the pioneer communities adds some organic matter to the soil environment, and favours the establishment of new species. (b) Factors which affect population size are: (i) availability of resources (e.g. water, space, food, resting sites, nesting sites) (ii) existence of other organisms which compete for resources in the environment (interspecific competition) and thus decrease the size of the population (iii) predators/organisms feeding on the members of the population (iv) existence of parasites and pathogens which cause diseases and thereby reduce the population size. (v) abiotic factors such as climatic factors, e.g. rainfall temperature, humidity, topography, soil and edaphic factors (vi) natality and mortality effects on the population size (the greater the mortality, the less the population but the greater the natality, the greater the population size). (vii) over crowding (viii) migration, emigration, dispersal and immigration. (c) Adaptation of tapeworm Taenia solium to its habitat in gut of human: (i) Tapeworm possesses hooks on the scolex for attachment to gut wall. (ii) It possesses suckers for attachment to gut wall. (iii) It has a ribbon-like, flatten or tape-like body to fit into the gut of host. (iv) It has a fast rate of proliferation of proglottides to ensure survival of the organisms or ensure perpetuation of the species. (v) Large surface area of its body allows absorption of food from the gut. (vi) It is a hermaphrodite and this allows successful sexual reproduction (vii) The surface of its body is thin and permeable and allows rapid absorption of food. (viii) The wall of its body is resistant to digestion by host digestive enzymes (ix) Mature proglottides loaded with eggs are detached and expelled with faeces of the host for dispersal.

Hint: Use BODMAS, in other words, do multiplication of the second and the last first before subtracting value obtained from the first.

\((\sqrt[3]{64a^{3}})^{-1} = (\sqrt[3]{(4a)^{3}})^{-1}\) = \((4a)^{-1} \) = \(\frac{1}{4a}\)

\(\frac{p^{2} - q^{2}}{2pq} = \frac{(p + q)(p - q)}{2pq}\) = \(\frac{(1 + \sqrt{2} - (1 - \sqrt{2}))(1 + \sqrt{2} + 1 - \sqrt{2})}{2(1 + \sqrt{2})(1 - \sqrt{2})}\) = \(\frac{(2\sqrt{2})(2)}{-2}\) = \(-2\sqrt{2}\)

Total cost = N(250,000 + 70,000) = N320,000 Selling price = N400,000 (given) Gain = SP - CP = N(400,000 - 320,000) = N80,000 Gain % = gain/CP x 100 = (80,000/320,000) x 100 Gain % = 25%

\(x = \frac{y}{2} \) \(\left(\frac{x^{3}}{y^{3}}+\frac{1}{2}\right) \div \left(\frac{1}{2} - \frac{x^{2}}{y^{2}}\right)\) \(\frac{x^3}{y^3} + \frac{1}{2} = (\frac{y}{2})^{3} \div y^{3} + \frac{1}{2}\) = \(\frac{y^{3}}{8} \times \frac{1}{y^3} + \frac{1}{2}\) = \(\frac{1}{8} + \frac{1}{2}\) = \(\frac{5}{8}\) \(\frac{1}{2} - \frac{x^2}{y^2} = \frac{1}{2} - (\frac{y}{2})^{2} \div y^2)\) = \(\frac{1}{2} - \frac{y^2}{4} \times \frac{1}{y^2}\) = \(\frac{1}{2} - \frac{1}{4}\) = \(\frac{1}{4}\) \(\therefore \left(\frac{x^{3}}{y^{3}}+\frac{1}{2}\right) \div \left(\frac{1}{2} - \frac{x^{2}}{y^{2}}\right) = \frac{5}{8} \div \frac{1}{4}\) = \(\frac{5}{2}\)

Principal, P = Amount, A - Interest, I. A = P + I I = (P.T.R)/100 = (P x 5 x 2)/100 = 10P/100 = P/10 But A = P + I, => 5500 = P + (P/10) => 55000 = 10P + P => 55000 = 11P Thus P = 55000/11 = N5,000

\(\frac{(0.14)^{2} \times 0.275}{7(0.02)} = \frac{(0.14)^{2} \times 0.275}{0.14}\) = \(0.14 \times 0.275\) = \(0.0385 \approxeq 0.039\) Note: Embedded zeroes are counted just the same as non-zero digits and For the number of decimal places stated, count that number of digits to the right of the decimal and underline it. The next number to its right is called the 'rounder decider'. If the 'rounder decider' is 5 or more, then round the previous digit up by 1

\(\frac{a^{3x} - 26a^{2x} + 156a^{x} - 216}{a^{2x} - 24a^{x} + 108}\) Let \(a^{x} = z\) \(\therefore = \frac{z^{3} - 26z^{2} + 156z - 216}{z^{2} - 24y + 108} ... (i)\) Dividing (i) above, we get \(z - 2\) = \(a^{x} - 2\)