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

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

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

(a) (i) Forms in which living cells exist Single/free-living Colony/colonial Filamentous/filament Part of a living organism. (ii) Example Single/free-living -Amoeba/Chlamydomonas/Paramecium/Euglena Colony/colonial -Eudorina/Pandorinallolvox/Sponges Filamentous/filament - Spirogyra/Chladophora/Ulothrix/Zygnema/Oedogonium Part of living organism - cheek cell/onion cell/epidermal cell/parenchyma cell. (b) Diagram of a typical plant cell (c) (i) Differences between a plant cell and an animal cell plant cell Animal Has cellulose cell wall / rigid Lacks cellulose cell wall Has one large central vocoule has numerous/vocoule has chloroplast lacks chloroplast Contains starch granules in its cytoplasm contains glycogen granules in it cytoplasm Usually larger in size Usually smaller in size Does not have lysosome has lysosome Does not have centrioles / centrosome Has centrioles / centrosome Has a regular / defined cell shape has an irregular / indefinite cell shape cytoplasm less dense cytoplasm more dense stores lipid as oil stores lipid as fat (ii) Similarities in plant cell and animal cell; They both have cytoplasm; nucleus; vacuole; mitochondrion; Golgi body; (smooth/rough) endoplasmic reticulum; cell membrane/plasma membrane; ribosomes

(a) Organs of alimentary canal of humans in sequence Mouth/buccal cavity Oesophagus/gullet Stomach Duodenum Ileum/jejunum/small intestine Caecum/Colon/Large intestine Rectum. (b)(i) Structural differences between the alimentary canal of a bird and human Bird Human Beak present / mouth modified to beak Beak absent / present of mouth Teeth absent teeth present Crop present crop absent Gizzard present gizzard absent Anal pore modified to cloaca anal pore modified to anus Shorter alimentary canal Longer alimentary canal Appendix absent appendix present (ii) Similarities in the alimentary canal of a bird and human; They both have mouth; oesophagus/gullet; stomach; duodenum; small intestine; large intestine; caecum; rectum. (c) Adaptation of the dentition of herbivores for feeding Elongated/curved incisors; for cutting grass/herbs Thick horny pad; against which the lower incisors bit Canines are absent/presence of diastema; allows tongue to roll the cropped grass Broad surfaces of the cheek teeth/molars; for grinding/chewing/masticating. Ridges/furrows on cheek teeth/molars; for grinding/chewing/masticating (d) Roles of pancreas in digestion Produces pancreatic juices which contain enzymes Sodium bicarbonate in the pancreatic juice neutralizes the HCL from the stomach/produces alkaline medium Pancreatic amylase digests starch to maltose Trypsin in the pancreatic juice digests protein to peptides/peptones Lipase in the pancreatic juice digests fat droplets to glycerol and fatty acid

(a)(i) Habitat The natural dwelling place of an organism. OR A place/locality where an organism lives successfully (ii) Role of a decomposer in an ecosystem Decomposers are organism which bring about the decay of dead parts/whole of plants/animals; to produce manure/humus; they release nutrients in them into the soil; which are absorbed by roots of plants; and are used to build up new plant tissues; they thus help in nutrient recycling; also release offensive gases/odour which pollute the air. (b) Energy flow in a freshwater habitat; Common aquatic plants/Pistia/Spirogyra/any correctly named aquatic plant; using energy from the sun; photosynthesize/produce food; the food is eaten by primary consumers/animals; small aqautic animals would be eaten by bigger aquatic animals/secondary consumers; tertiary consumer/a much bigger fish/any correctly named fish will feed on secondary consumer, in the process of feeding energy flows from one trophic level to another; decreases progressively; dead animals/plants decompose; energy is lost. (c)(i) Harmful effects of microorganisms to plants They cause diseases They can cause undesirable qualities in plants/plant product They cause spoilage Reduction in yield (ii) Beneficial effects of micro organisms to humans Bacteria/decomposers help to decay/decompose dead organisms to release nutrients Bacteria is used in cleaning/mopping up oil spillage Used in the fermentation of foods/cocoa beans/garri/locust beans/kenkey production Used to make vinegar Used in making alcoholic beverages/wine/beer/spirit Used in making some antibiotics/penicillin Used in the manufacture of insulin Used in making cheese/yoghurt/bread/Single Cell Proteins Used in making flax/tanning of leather;

(a)(i) Agglutination; The clumping together; of antigens or red blood cells/RBC; with the corresponding antibodies in the plasma; of incompatible blood groups/wrong blood group. (ii) Donor Recipient A B AB O A B AB O (b) How each of the following organisms are adapted for obtaining food (i) Mosquito larva - Possess a pair of ciliated mouth brushes; for creating water current to carry water with food particle into the mouth; - Its mouth brushes; filter food out of water and sweep it into the mouth. (ii) Dodder plant - Possess haustoria; for penetrating host plant tissue to obtain food/water (iii) Grasshopper Possess mandibles/heavy toothed jaw-like structures; for cutting/crushing food/plant materials/vegetation Possess maxillae; for directing food to mandibles/cutting/grinding food Labrun; for holding food/ plant materials/vegetation Labium; for guiding foods/prevent it from falling off.

(a) Differences between tactic and nastic movements in plants Differences between tactic and nastic movements in plants Tactic movement Nastic movement movement of whole organism / entire plant movement shown by part of a plant movement is directly towards / from stimulus Non-directional movement stimuli consist of light / heat / chemical stimulus is touched / tugor pressure (b) Examples of organisms that show (i) Tactic movement Volvox Chlamydomonas Egulena earthworm tilapia (ii) Nastic movement Morning glory Mimosa Pride of Barbados (Caesalpinia) Four-o-clock plant Morning flower sunflower Desmodium clover (c)(i) Care of the skin Eating balanced diet rich in vitamins A/B2/E Engaging in regular exercise Washing the skin with clean water and soap daily; Drinking lost of water Moisturising/rubbing the skin with lotion/cream Avoilding excessive exposure to ultraviolent yars/radiation Avoilding bleaching creams/harsh chemicals Wearing clean clothes next to skin Protect the skin against injury. (ii) Stimuli to which the mammalian skin is sensitive Touch Pressure Heat Cold Pain Chemicals (d) Effects of high temperature on terrestrial habitat Causes high transpiration rate in plants Plants wither/wilt Leads to high rate of metabolism in both plants and animals There is a high rate of decay of organic matter Leads to high rate of growth; and shorter length of life cycle in toad/housefly Makes poikilothermic animals to look for shelter from heat/hibernation There is high rate of water loss in animals/sweating/perspiration Leads to high incidence of bush fires Migration/emigration (e)(i) Courtship behaviour in animals A type of behaviour/instinctive action in animals; that play an important role in attracting a compatible mate/ opposite sex; of the same species; for copulation/sexual reproduction (ii) Courtship behaviours in animals Pairing Territoriality Seasonal migration Smell/release of attractive sex hormones/odour Display of prominent colour patterns Mating calls/croaking/vocal displays/sound signal Dancing/attractive movements. (f) Examples of organisms that carry out holozoic mode of nutrition Goat rat lizard frog bird human any correctly named example; pitcher plants; sundew; bladder worths. (g) Use of fingerprinting in crime detection No two individuals have the same/identical pattern/contour of fingerprints/hence it is used for crime detection; fingerprints left behind by a criminal at the scene of a crime/door/table/weapon/on victim; provide a valuable clue in the detection and subsequent arrest of a criminal; the fingerprints left on the scene of crime are photographed; and the crime suspect's fingerprints are taken and compared with the fingerprint at the scene of crime; if it matches then the suspect is the criminal.

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

(a)(i) Habitats of Specimen S/Toad, U/Lizard and W/Locust: Specimen S: Wet/moist/damp land/under stone/damp grass/vegetation near freshwater ponds. Specimen U: House/walls/cracks/mountain slopes/trees/garden/farmland Specimen W: Vegetation/grassland/farm/trees/leaves (ii) Class to which Specimens S, U and W belong: Specimen S: Amphibia Specimen U: Reptilia Specimen W: Insecta (b)(i) Observable similarities in Specimens S and U: Both have: -eyes, head, (wide terminal) mouth, 2 pairs/4limbs/forelimb/hind limb, tympanic membrane/eardrum, nostrils, trunk. Observable differences between Specimens S and U: (ii) - Specimen S/Toad has poison gland but poison gland is absent in Specimen U/Lizard -Gular fold absent in Specimen S/Toad but Gular fold is present in Specimen U/Lizard - Presence of bulging eyes in Speciemen S/Toad, eyes are not bulging in Specimen U/Lizard - Scales absent in Specimen S/Toad but scales present in Specimen U/Lizard -Streamlined body in Specimen S/Toad, body not streamlined in Specimen U/Lizard - Warty skin on Specimen S/Toad but no warts on Specimen U/Lizard - Absence of tail in Specimen S/Toad but tail is present in Specimen U/Lizard - Absence of nuchal crest in Specimen S/Toad but nuchal crest is present in Specimen U/Lizard - Neck absent in Specimen S/Toad but present in Specimen U/Lizard - Digits of hind limbs of Specimen S/Toad are webbed, but not webbed in Specimen U/Lizard - No claws on the digits of Specimen S/Toad but digits of Specimen U /Lizard end in claws - In Specimen S/Toad the forelimbs end in four digits, but in Specimen U/Lizard the forelimbs end in five digits -Body is short and wide in Specimen S/Toad but long and narrow in Specimen U/Lizard. (c)(i) Sex of Specimen U: Male. (ii)Reasons for the answer in 4(c(i): -Brightly colored with red head/blue black trunk; - Blue and orange tail; Presence of Gular fold -Prominent Nuchal crest - Presence of hemi-penis (d) Observable features that adapt Specimen S to its habitat - Poison gland; for protection; - Warty skin; for camouflage -Webbed digits of hind limbs for swimming; - Bulging eyes; for wide vision; - Muscular forelimbs; for absorbing shock - Long muscular hind limbs for jumping/hopping -Cryptic coloration for camouflage; - Moist skin for (cutaneous) respiration; -Forelimbs have pads for absorbing shock during landing. (e) Food chain: Specimen T/grass => Specimen W/Locust => Specimen S/Toad Specimen T/grass => Specimen W/Locust => Specimen U/Lizard

(a) Food Test Observation Result Specimen A/bread/it; turns blue-black/blue/black Starch present Specimen E/orange juice turns brownish/yellowish Starch absent (b)(i) Observable differences between specimens A and B -Specimen A is white/ cream in color while specimen B is dark brown/black in color -Specimen A is soft in texture while Specimen B is hard in texture -Absence of mould/Rhizopus/Mucor in specimen A, while in specimen B, there are presence of mold/mould, fungus/fungi/Rhizopus/Mucor. - Specimen A is fresh, while specimen B is stale/decaying (ii) Factors responsible for the state of Specimen B - Moisture/water/humid air/humidity; -Warmth/temperature - Spores of fungus/fungi; - Time. (iii) Name of Organism : Mold/mould/fungus/fungi/Rhizopus/Mucor. (iv) Mode of feeding Saprophytic. (c)(i) Diagram/drawing of longitudinal section of Specimen C/boiled egg (ii) Function of labeled parts: -Shell: Protection/aeration/shape/gaseous exchange; -Shell membrane allows gaseous exchange, -Albumen: Supplies protein; -YoIk: Provides food for embryonic growth/embryo; - Air space: allows exchange of gases; - Chorion protects the embryo/yolk sac.

(a) Location of Specimens H, K and M In the body of a mammal Specimen H/Liver: Below the diaphragm/upper part of the abdominal cavity/abdomen. Specimen K/Lung: Thoracic cavity/chest/thorax/thoracic region: Specimen M/Kidney: Located at the dorsal wall of the abdominal cavity/abdomen. (b)(i) Fluid in Specimen L: Bile (ii) Functions of the fluid in Specimen L: - It emulsifies fats (and oils into fat droplets); -The inorganic salts in it neutralize the acid in the chyme/bile neutralizes chime - It provides alkaline medium for pancreatic juice to act; - It prevents the decay of food in the small intestine. - It gives brownish and yellowish coloration of feces. (iii) Other Specimen that Specimen L is associated with Specimen H/Liver. (c)(i) Observable differences between Specimens H/Liver and K/Lung -Specimen H/Liver is more solid/thick/turgid while Specimen K/Lung is soft/softer/fluffy/spongy -Specimen H/Liver is darker/dark red in color while specimen K/Lung is brighter/red/pink in color Specimen H/Liver is smoother on the surface while Specimen K/Lung is folded/convoluted surface. (ii) Observable features that adapt Specimen K/Lung to its function: - Moist/wet surface; for dissolving gases/O\(_2\) /Co\(_2\), - Thin surface membrane for easy diffusion/exchange of gases; - Many blood vessels/highly vascularised/for transportation of gases/dissolved food substances (d) Biological importance of Specimens K/Lung and M/Kidney: Specimen K/Lung Surface for inspiration and expiration/exchange of gases/respiration. Specimen M/Kidney - Osmoregulation; - Production of urine/excretion/excretion of metabolic waste; - Maintenance of acid-base balance (e) Drawing/diagram of longitudinal section of Specimen M/Kidney

If logx 64 = 3, then \(64 = x^3\) \(4^3 = x^3\) Since the indices are equal, x = 4 Hence, x log\(_2\)8 = 4(3.log\(_2\)2) = where log\(_2\)2 = 1(1) = 12 X 1 = 12

If m = 4, n = 9, r = 16, then \(\frac{m}{n}\) - 1\(\frac{7}{9}\) + \(\frac{n}{r}\) = \(\frac{4}{9}\) - \(\frac{16}{9}\) + \(\frac{9}{16}\) = \(\frac{64 - 256 + 81}{144}\) = \(\frac{-111}{144}\) = - \(\frac{37}{48}\)

In a school with students' population 810, the sectoral angle for a class of 72 students is = \(\frac{72}{810}\) x 360º = 32º