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

Reasons why termites are most active during the night: Avoiding Predators: By coming out at night, termites try to avoid their predators like birds, ants, and other insects, who might feed on them during the day. So, this is their self-defense mechanism. Nesting Behavior: Termites feel more secure during the night. They prefer building new colonies in the ground or inside the woods at night. They feel more secure traveling between their food sources and nests without worrying about being noticed. Feeding Patterns: Another reason for termites to come out at night is their feeding pattern. These silent destroyers feed on paper, wood, and other organic matter. They prefer emerging out at night in search of food without any disturbance, which is more common and frequent during the daytime. Colony Organization: Termites usually organize their colonies in different sections like soldiers, workers, and reproductives. Worker termites being more responsible as well as sensitive to the daytime environments, prefer carrying out their responsibilities during the darkness of night. Conserving Moisture: Termites can easily dry out and look for ways to conserve moisture to survive. This is not possible during the daytime when the temperature is high, so they come out at night when the air is cooler and humidity levels are higher so that they can conserve moisture for survival.

(b)(i) Diagram of the Human Ear (a) How the human ear carries out its function of balancing; - Head movement in any direction affect the fluid/endolymph, In the semi-circular canals, Which are at right angles to each other, The movement forces the sensory/hair cells in the ampulla to set up the impulses, The brain interprets the impulses and relays the impulses to the body muscles for balancing. (b)(i) Diagram of the Human Ear; (b)(ii) Description of the structure of the middle ear; The middle ear is an air filled chamber, It connects the ear drum of the oval window fenestra ovalis. It contains three bones/hammer/malleus, anvil/incus and stapes/stirrup/ear ossicles. The malleus is attached to the tympanic membrane/tympanum/eardrum. Each of the bones has direct contact with the one next to it, the eustachian tube is formed at the base of the middle ear . The eustachian tube links the ear to the throat/pharynx.

(a)(i) Deficiency Disease; This is a disease caused by lack of or insufficient or inadequate supply of a specific vitamin or other nutrients/food substances. (a)(ii) Nutrient deficiency diseases Remedy Goitre/Goiter Consumption of iodizes salt/sea food Rickets Consumption of a diet rich in calcium/phosphorous/vitamin D Anaemia/Anemia Eating a diet rich in iron Kwashiokor Diet of infant should contain protein Scurvy Consumption of foods/fruits rich in Vitamin C Pellegra Addition of naicin/vitamin K to diet Night blindness Consumption of food rich in Vitamin A Beriberi Consumption of food rich in vitamin B Stunted growth/cretinism Consumption of food rich in iodine Marasmus Consumption of protein and carbohydrate (b) Procedure of Chemical Test for; (i) Starch in a tuber of yam; The tuber of yam is peeled and sliced, a few drops of iodine solution is added to the peeled yam, blue-black colour formed indicates presence of starch. (ii) Glucose in orange fruit; Orange fruit is cut and it's juice is extracted into a beaker/test tube, few drops of Benedict's solution/Fehling's solutions A and B is added to equal volume of orange juice, add heat gently, a red/orange/brick-red precipitate shows the presence of glucose. For Benedict's solution when heated shows red/yellow precipitate confirming presence of glucose

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

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

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

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The process that gives rise to \(F_1\) generation is cross fertilization.

(a) Disease Causative Organism Vector Control Cholera Vibrio Cholerae Housefly/Cockroach Good sanitation/good personal hygiene/ any other method of good sanitation/inoculation/vaccination Trypanosomiaasis/Sleeping sickness Trypanasome Tsetsefly/Glossina Destroying habitat of vector/clearing the vegetation, killing vector/ eradicate flies. Malaria Plasmodium sp Penale anopheles mosquito Proper sanitation/using spraying recommended insecticide/fumigation, clearing of bushes/drainages of breeding sites/sleeping under nets. Ringworm Tinea Sp/Fungi/Microsponium None Good personal hygiene, avoid contact with infected persons/material, use of drugs/griseofluvin (b) Biological Basis of Preserving Foods by; (i) Salting; Removes water/moisture from food by osmosis therefore prevents micro-organisms from growing on food by dehydrating and killing them. (ii) Irradation; Involves the exposure of food to high energy gamma rays/x-rays radiation to destroy enzymes that cause spoilage, delay ripening of fruits, sprouting of vegetables therefore allowing long storage periods. (iii) Smoking; Reduces the water content of food thereby creating unfavourable conditions for microbial growth and survival also called curing. Smoking contains phenols/carbon that kills microbes on the surface of food.

(a)(i) Independent Assortment of Genes; is the random selection of genes during meiosis to produce gametes, where the genes separate/segregate so that only one of a pair is found in any one gamete. In the dihybrid inheritance in heterozygote the pairs of alleles are found on different pairs of chromosome, Only four types of gametes are produced in approximately equal numbers. (ii) Blood grouping in humans; Is determined by three alternative genes/alleles A, B and O. A person can only possess two alleles of the genes on a pair of homologous chromosomes. Gene O is recessive to both genes A and B which are dominant/co-dominant and possess antigen A and B in the red blood cells hence it is possible to have blood group A as AA (homozygous) or AO (heterozygous) and blood group B as BB or BO, Blood group O can only exist genotypically as OO and does not possess antigen A or B in the red blood cells or in the homozygous recessive state. (b) Classes of Vertebrates in their Evolutionary Trend; Class of Vertebrates One Example Pisces/Osteichthyes/Chondricthyes Tilapia; Tuna, Salmon, Shark, Dogfish, Catfish, Skate, Ray Amphibia Frog/Toad Reptilia Snake, Crocodile, Tortoise, Turtle, Lizard, Wall Gecko Aves Dove, Pigeon, Parrot, Weaver Bird, Hawk, Eagles, Domestic Fowl Mammalia Human, Monkeys, Rat, Rabbit/Guinea pig

(a)(i) External Fertilization; Involves the release of eggs by the female to the outside environment where a male sheds its sperms on them for fertilization outside the body of the female. (ii) Internal Fertilization; Involves the release of eggs inside the body of a female males deposit sperms inside the female where fertilization occurs. (b)(i) Groups of Animal that exhibit external fertilization ;- Fish/pisces, amphibians (ii) Groups of Animal that exhibit internal fertilization;- Reptiles, birds/aves, mammals (c)(i) Effect of Detached Placenta on a Foetus; The exchange of dissolved food substances/oxygen/antibodies between a foetus and the mother will cease, removal of waste products from foetus will cease production of progesterone/hormone will cease might lead to the death of foetus/miscarriage/abortion/still birth. Certain molecules may pass into the body of foetus. (ii) Other Features Present in the Uterus of a Pregnant Woman; Umbilical cord, amnion, amniotic fluid, allantois, Chorion (d) Dynamic Equilibrium; Nature does not encourage any population exceeding the carrying capacity of the habitat, living organisms play a role in the regulation of the abundance of organisms/population in the habitat. Interaction among various populations lead to competition which may result in the elimination of one species or its restriction to a non-competitive position, Plants sometimes compete by producing toxic chemicals that inhibit neighboring species, there also exists predator-prey relationship/association between animals all these forces act together to achieve dynamic equilibrium in the habitat. (e) Problem that Organisms in Intertidal Zones of Marine Habitats could Encounter; Tendency of being carried away by waves drying up/desiccation/exposure to air, varied osmotic balance oxygen deficiency, low light intensity for producers, reduced visibility in animals, fluctuation of water temperature.. (f) Reasons the following factors are necessary for germination; (i) Moisture;- A seed imbibes/absorbs moisture causing the seed to swell and the testa becomes more permeable to oxygen and carbon (IV) oxide. This swelling will rupture the testa before germination starts, the moisture/water activates the enzymes for metabolism leading to germination (ii) Viable Seed;- Has a living/healthy embryo, intact healthy cotyledon/endosperm, whole without boring from insect. (g) Reason Light energy is Considered a Limited Factor in the Production of Food by Autotrophs; Light energy is obtained from the sun which is an important factor for photosynthesis/photolysis of water that is a process of manufacturing/producing food by autotrophs at optimum temperature/sunlight/solar/light energy green plants/autotrophs will manufacture food.

1.Study Specimens B, C and D and answer questions (a)(i) Place two drops of specimen B on a white tile and add two drops of iodine solution. Complete table below with the test, observation and inference: Test Inference Observation Two drops of iodine solution was added to two drops of Specimen B on a (white tile) Brown/Yellow color remains unchanged/no (visible) Starch absent Test Observation Inference 5mls of specimen B was put into a test tube +2mls of sodium hydroxide solution+ three drops of copper (ii) tetraoxosulphate (VI) solution and it was shaken Violet/Purple color formed Protein present (b) (b) Name of Test: (i) lodine test/test for starch (II) Biuret test/test for protein. (c) Economic Importance of Specimen C/Mushroom:- -Facilitates nutrient cycling. -Facilitates decay. -Used as -Source of income/employment. -Manufacture of drugs. food/source of food (d)(i) Kingdom of Specimen C: Fungi/Mycota: (ii) Reason for Kingdom of Specimen C: -Lacks chlorophyll. -Is filamentous. -Reproduces (asexually) by spores/conjugation. -Has hyphae/mycelium. of cellulose cell wall/chitin/glucans/protein. -Saprophytic/heterotrophic nutrition. (iii) Other organisms that belong to the Kingdom of Specimen C: Mucor/Mould: -Aspergillus; - Yeast; -Rhizopus; toadstool;-Puffball: -Puccinia/black rust/rust; -Smut;-Penicillium; -Bracket fungus;-Pythium fungus. (e)(i) Phylum of Specimen D/Giant Land Snail: Mollusca. (i) Reason for Phylum of Specimen D: -Has shell; -Has tentacles; -Body divided into head, Viscera hump and muscular foot; muscular foot;-Has a mantle/mantel. (f) Role of Specimen C in Nutrient Cycling: -They are decomposers; -They release nutrients into the soil;-Which plants absorb for growth;-Herbivore feed on plants. (ii) Mode of nutrition of Specimen C: Saprophytic

(a) Type of Fruits of Specimens E/Pawpaw fruit, F/Tomato fruit and H/Pod of Pride of Barbados: (b) Placentation of Fruits of Specimens E/Pawpaw fruit and F E: Berry F: Berry H: Legume. (b) Placentation of Fruits of Specimens E/Pawpaw fruit and F Tomato fruit. E: Parietal F: Axile. (c) Agents of Dispersal of Specimens E/Pawpaw fruit, F/ Tomato fruit and H/Pod of Pride of Barbados: E: Man/Human/animal/any correctly named animal F: Man/Human /animal/any correctly named animal H: Explosive mechanism (d)i) Explanation of how Specimen E is dispersed:-The epicarp is brightly colored;-Which attracts man/humans/ animal/correctly named animal; -To eat its succulent parts (mesocarp and endocarp);-then eventually -Which attracted man/humans/ throws away its seed/plants it. (ii) Nutrient present in Specimen E: -Vitamins; -Carbohydrate -Protein/amino acid/calcium/magnesium/potassium/zinc/phosphorus/iron/ Carbohydrate: fructose/sucrose/sugars copper/manganese; -Mineral salts; -Water; -Riboflavin (e) Color of Specimen H: Green. (ii) Significance of the Color of Specimen : It indicates that the fruit contains chlorophyll / is photosynthetic. (f(i)) Type of Placentation of Specimen H: Marginal.

x = 180\(^o\) - (52\(^o\) + 70\(^o\)) = 180\(o\) - 122\(^o\) = 58\(^o\)