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Phytoplankton are plant-like, microscopic organisms, specifically algae and some bacteria, that live in water and perform photosynthesis, similar to land plants. Hence, they are the primary producers. However, the herbivore will feed on them. The tadpole being placed directly after the phytoplankton means it will be the herbivore (the primary consumer).

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Camouflage is a method of cryptic or concealing coloration that allows an otherwise visible organism or object to remain indiscernible from the surrounding environment through deception. Examples include a tiger's stripes

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1. The structural differences between the nymph of cockroach and an adult cockroach are: Adult Cockroach Nymph Winged/Wings present Wingless/presence of wind buds More prominent anal styles Less prominent anal style Prominent egg pouch Less prominent egg pouch Bigger /named body part Smaller /Corresponding named body part. More prominent cerci Less prominent cerci Long antenna short antennae 2. Characteristic features of cross- pollinated flowers are: Protandry/stamen/androecium ripening before the gynoecium/pistil, Protogyny /pistil/ gynoecium ripening before the stamen/ androecium, Unisexual flower, Self sterility, brightly colored, Scented, presence of nectar - sticky/rough/spiny pollen grains sticky stigma - light pollen grains 3. Testes in most mammals are located outside the body cavity to ensure that the testes can remain at a temperature lower than the normal body temperature as the body temperature is too high for sperm formation. The temperature of the scrotal sac is more conducive for sperm production. 4 (a) Ameba uses pseudopodium /pseudopodia/false foot/ false feet for movement. (b) Euglena uses flagellum- flagella for movement, (c) Paramecium uses cilia /cilium for movement. 5. The types of stimuli detected by the sensory nerve endings on the skin are: touch/tactile,pressure, temperature, pain. 6. Functions of the ciliary muscles of the eye are to alter the shape of the lens, so as to control its focussing power accommodation 7. (a) Four "daughter cells" are produced in meiosis and (b) Two daughter cells for mitosis. 8. (a) Species is adapted to cold conditions/ temperate /cold regions with a temperature of O^\circC 11^\circC and therefore, its distribution will not be wide geographically, Species lll is adapted to 10^\circC- 40^\circC, hence a wide range of distribution. It is likely to be found in warm temperature of hot tropical regions (b) Optimal temperature for growth of Species I is 4/5^\circ/6^\circ C. (4^\circ-6^\circC); Optimal temperature for growth of Species ll is 14^\circ/ 15^\circ/ 16^\circC. (14^\circ- 16^\circC), Optimal temperature for growth of Species lll is 22^\circ/ 23^\circ/24/ 25^\circ C (22^\circ-25^\circC) 9. Abiotic factors which plants growing close to each other may compete for are: nutrients, mineral salts, light, sunlight, sunshine, solar energy, water, moisture, space. 10. Four excretory products of plants are: CO2/carbon IV oxide /carbon dioxide O\(_2\) / oxygen, Alkaloids (e.g. cocaine/ morphine/quinine/etc), Resins: e.g - gums, latex, mucilage, tannins, ammonia, water/water vapor. 11. (a) (i) Specimen A= Pelvic girdle, osinnomination, half pelvic girdle; Specimen B = small mammal, e.g. rat, rabbit, guinea pig, mice, squirrel etc. Specimen C= Toad, frog. Specimen D =Leaf of a dicotyledonous plant, e.g.mango, orange leaf. Specimen B Mammal /mammalia Specimen C Ampibia /amphibian Specimen B Kidney/skin/lung Specimen D Stoma/Stomata /stomates (Some of the external features used by specimen C for gaseous exchange are: skin, (external), nostril/nares- buccal cavity/mouth (C) Similarities between specimen B and C: (1) 2 pairs of limbs (2) a pair of eyes (3) a pair of hearing organs/ears (4) nostrils/nares for external respiration/ gaseous exchange (5) both have anterior opening (mouth) and posterior opening (anus) (6) Limbs end up in digits (ii) Structural differences between Specimens B and C Mammal (B) Toad (c) Pinna present Pinna absent Hair present Hair absent Tail present Tail absent Body not watery Body watery Digits end in claws Digits without claws Toes not webbed Webbed toes Nictitating membrane absent in the eye Nictitating, membrane present in the eye Whiskers present Whiskers absent No bulging eyes Bulging eyes present Neck present Neck absent or no distinct neck Limbs with five digits Limbs with four digits Poison gland absent Poison gland present. 12. a . Specimen E = Vertical section of ( bird's ) egg or longitudinal section of ( bird's ) egg 13. (a) F = Maize/Corn (grain); G = Onion /onion bulb/bulb; H Ginger/rhizome; I = Cowpea / bean/ bean seed Cocoyam /corm/potato (stem) tuber: K= Oil palm seed/kernel or coconut seed/endosperm. (b) Specimen Annuals Perennial Cash Crop Food Crop F = Maize ✓ ✓ G = Onion ✓ ✓ H = Ginger ✓ ✓ ✓ I = Cowpea ✓ ✓ J = Cocoyam ✓ ✓ K = Oilpalm / Coconut ✓ ✓ ✓ (d) Difference between specimens F and l F(Maize grain) I (Cowpea) - Remains of style present/two scars present Pericarp present Pericarp absent Testa and pericarp fused Only testa present Only one cotyledon present Two cotyledons present Endosperm present Endosperm absent

(a)(i) The two stages involved in photosynthesis are: Light reaction stage or photolysis or Hill's reaction and Dark reaction stage or Carbon assimilation or Calvin reaction. (ii) Equation to represent Photolysis 4H\(_2\)O Light 4H\(^{+}/) + 4OH\(^{-}/) → chloropyll (b)(i) Modes of nutrition in organisms are: (1) Holozoic nutrition (2) Parasitic nutrition (3) Symbiotic nutrition (4) Carnivorous /Insectivorous/Piscevorous nutrition (5) Herbivorous nutrition (6) Chemosynthetic nutrition (7) Photosynthetic/Autotrophic /Holophytic nutrition (8) Ominivorous nutrition (9) Heterotrophic nutrition (b)(ii) Features that made feeding possible in: (1) Paramecium are: Food vacuole/cilia/ oralgroove/gullet/cytostome (II) Spirogyra are: Chloroplast/chlorophyll (III) Rhizopus are: Mycelia/Rhizoids / Hyphae (IV) Tape worm are: Body surface/flat body/body. (c) A balanced diet; is a diet containing the correct proportion or right amount of all the six food substances or names of the six food substances or essential food subtances required by the organism/man. OR A balanced diet contains 15% protein, 15% fats and oils, Vitamins, 10%Minerals water and 60% carbohydrates. (d)(i)Characteristics of enzymes are: Enzymes (i) speed up chemical reactions or act as catalysts (ii) are specific in action (iii) are not used up or changed during reaction (iv) Actions of enzymes are reversible. (v) are affected by temperature or denatured at high temperature (vi) are affected by pH of their surrounding (vii) Some enzymes act best in the presence of co-enzymes. (vii) Enzymes can function outside organisms producing them. (ix) are protein in nature (x) Enzymes have active sites. (xi) Small amount of enzymes catalyze large amounts of substrate. (d)(ii) Enzyme Source Substrate Product Ptyalin Pepsin Mouth/salivary Gland/ saliva Stomach/Gastric Starch/ Cooked starch Proteins gland/ Gastric juice Maltose/ Malt Sugar/dextrin/ dextrose Peptones/ Polypeptides/peptides

a(i) Four Floral parts of a flower are: (1) calyx/sepals (2) corollapetals (3) androecium/stamen, filament, anther, pollen grains (4) gynoecium/pistil/carpel (5) stigma, style, ovary, pedicle, receptacle, ovules. (b)(i) Differences between wind and insect pollinated flowers are: Wind pollinated flowers Insect pollinated flowers - Flowers are small or inconspicuous - No scent, odour or smell - No nectar - Have no particular shape - Flowers not brightly coloured - Produce large quantity of pollen grains - Smooth pollen grains - Pollen grains not sticky /powdery - Light pollen grains - Stigmas are large, feathery providing large surface area -Flowers are large and conspicuous. -Scented/possess scent/odour -Nectar present -Flowers are specially shaped to facilitate pollination by particular types of insects. -Flowers are usually brightly coloured. -Produce relatively small quantity of pollen grains -Rough pollen grains /Spiky pollen grains -Pollen grain are not light/heavy -Stigmas are flat/have small surface area (b)(ii)Examples of wind pollinated flowers are Maize, Millet, Rice, Oat, Grass while examples of insect pollinated flowers are Delonix, Tridax, Eurena, Sunflower, Basam, Mango, Pride of Barbados, Thumbergia, Hibiscus. (c) Agents of fruit and seed dispersal are: (i) Wind - tecons,cotton, tridax, aspilia, emilia etc. (ii) Animal-mango, pawpaw, oranges etc. (iii) Explosive mechanism - flamboyant, pride of barbados, okra, oil bean, castor oil seed, balsam etc. (iv) Man - Cocoa, rubber, oil palm, cassava, coconut, etc (v) Water coconut, mangrove, water-lily, etc. (d)(i) Hormones are organic/chemical susbtances/bio chemical substances produced in minute quantities in one part of an organism and transported to the site of action where they exact specific effect to control body metabolism. (ii) Examples of plant hormones are Indole -3- acetic acid/Indole acetic acid (I AA), Gibberellin, Florigen, Cytokinins, Put Abscussin/abscissic acid, Traumatin 2,4, dicholorphencxy ethanoic acid ( 2- 4 -d) auxin. (iii) Examples of effects of plant hormones are; (1) Promotes abscission of leaves. (2) Induces dormancy in buds/seeds. (3) Promotes ripening of fruits/maturity/flowering. (4) Encourages parthenocarpy (5) Promotes apical dominance (6) Promotes growth (7) Excess inhibits growth in root/ it retards growth in roots when in excess/high concentration (8) delays abscission in young leaves