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During photosynthesis, water is absorbed by the roots of the plant and transported upwards through the xylem to the leaves. In the leaves, water is used in the photosynthetic process to produce glucose and oxygen. From the options, option D is correct because oxygen is produced as by-product.

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

Birds of prey, also known as raptors, have feet and beaks that are adapted for grasping, killing, and tearing flesh. Raptors have strong feet for striking and grasping prey. They have sharp, curved claws on their toes for gripping prey and puncturing skin. Raptors have sharp, hooked beaks for piercing, plucking, and pulling apart prey.

- Like frogs, most toads lay their fertilized eggs in water, where they hatch into tadpoles before developing into adult toads. These amphibians need a safe, undisturbed body of water to lay their eggs in. However, a few species breed on land. - the mother alligator typically lays about 35 eggs in a nest made of mud, sticks and other plant matter. - Rabbits sometimes dig a burrow in which to give birth

Embryos of vertebrates can be used to show evolutionary trend: - Fishes → Amphibians → Reptiles → Birds → Mammals

(a) Types of fruit: C- Berry/hesperidium. D-Capsule. E-Legume/Pod. F-Cypsela. G Berry/hesperidium. H-Drupe. (ii) Types of placentation with reasons: Specimen C Pepper - Axile - Ovules are attached to central placenta. E Beans pod -Marginal - Ovules are arranged in a single row at the margin of an ovary. G Orange-Axile- Ovules are attached to central placenta. (b)(i) Modes of dispersal: C/ Pepper - Animal/Man D/Castor oil Explosive mechanism. E/ Bean pod - Explosive mechanism. F/ Tridax -Wind G/ Orange -Animal/Man. H/Coconut- Water/Man. (ii) Dispersal of specimen D/Castor oil fruit: - The fruit matures ripens and dries up. Tension is set up in its fruit wall. - Due to uneven drying of the fruit wall/pericarp dries unevenly. - Fruit splits with explosion along weak lines. - Seeds are scattered. (c) Differences between Specimens G and H Specimens G/O Orange: Epicarp and mesocarp fused; Endocarp is succulent/fleshly/soft; Many seeds; Many chambers in fruit; Mesocarp is membranous/leathery; Axile placentation; Specimen H/Coconut: Epicarp and mesocarp separate; Endocarp is hard/stony; One seed; Only one chamber in fruit; Mesocarp fibrous; Parietal placentation.

(a) Adaptation: These are special features/characteristics that an organism possesses, which enable it to live/ survive successfully in an environment (b)(i) Aloe: - The succulent leaves are adaptations for water storage. They are also adapted for surviving high temperatures and drought. (ii) Cactus: Stems are thick and succulent for water storage, while leaves are reduced to conserve water, by reducing rate of transpiration. (iii) Fowl: The beak is short/ strong/straight for picking insects/seeds, earthworms/small pieces of food, pecking of feathers. (iv) Fish: The dorsal side is dark while the ventral side is silvery/counter shading. - This dual coloration protects the fish from predators, looking at them from above and below the water. (v) Pines: The needle like leaves reduce water loss by transpiration. - Also conserves water for use in the long dry season. (c)(i) Population: This is the total number of individuals of the same species, living together in a habitat, at a given time. (ii) Effects of over population: - Competition for limited resources. Predation/cannibalism. Spread of diseases. Food shortage. build up toxic waste in the environment. Limited space for individual dwellings. High mortality/mortality rate. Increase of social vices/behaviour.

(a) Chemical Equations for processes: (i) Aerobic respiration C\(_6\)H\(_1\)\(_2\)O\(_6\) + 6O\(_6\)→ 6CO\(_2\) + 6H\(_2\)0 + 38ATP Energy/690k cal. (ii) Anaerobic respiration in plants C\(_6\)H\(_1\)\(_2\)O\(_6\) --> 2C\(_2\)H\(_5\)OH + 2CO\(_2\) + 2ATP/Energy/50 k cal. (iii) Anaerobic respiration in animals C\(_6\)H\(_1\)\(_2\)O\(_6\_) → 2CH\(_3\)CH(OH)COOH + 2ATP/Energy/150 k cal. C\(_6\)H\(_1\)\(_2\)O\(_6\) → 2C\(_3\)H\(_6\)O\(_3\) + 2ATP/Energy/150 k cal. (b) A cancerous liver will not be able to: - regulate blood sugar carry out detoxication/deamination/regulation of blood proteins produce bile form red blood cells produce heat store vitamins regulate lipids manufacture protein store iron reserve blood. Labels: Cell lumen, nucleus, basal granule, flagellum/cilium, excretory duct, excretory tubule, cytoplasmic process, vacuole (d) Hormones responsible: - Ripening of fruit auxin/ethane/ ethylene/IAA Breaking of dormancy in seeds Auxin/ Gibberellins/cytokinins (kinta) Weed control Auxin/2,4 D/ 2,4 Dichlorophenoxyacetic acid Leaf fall Abscisic acid

(a)(i) Types of germination with examples: Epigeal germination e.g. cowpea/bean seed. Hypogeal germination e.g maize grain/wheat/oil palm/guinea corn. (ii) Experiment to demonstrate factors necessary for germination: Some dry cotton wool are placed at the bottom of each of conical flasks labeled A,B,C and D. In flask A, few/2 to 4 bean seeds are placed on dry cotton wool; the flask is placed in a warm place. In flask B the cotton wool is moistened together with the seeds in it Test tube containing pyrogailic acid and caustic soda/pyrogaliol is suspended in flask B; to absorb oxygen; flask B is put in a warm place In flask C a little water is placed on the cotton wool and seeds and it is placed in a warm place; In flask D a little water is poured on the seeds to moisten them and it is placed in the refrigerator the four flasks are observed for four to five days/few days; only the seeds in flask C germinated. This shows that oxygen, water/moisture and warmth are necessary for seed germination. (b)(i) Epiphytes: - A plant which grows on/supported by another plant/lives on trees Where it competes with other producers for sunlight It does not take manufactured food from the support plant It is capable of photosynthesis. (ii) Parasites: - An organism that lives on or in another organism is called a host it obtains shelter/protection/food from the host At the expense of the host/leading to harm/death of the host. (c) Examples of plant parasites: - Dodder Striga Mistletoe Cassytha

(a) Short notes: (i) Niche: Refers to a specific portion of a habitat/dwelling place which is occupied by a particular species of organism. It is also a functional position/role of an organism within the community. Each organism living in the same habitat has its own living space, source of food and tolerance for the effect of the habitat/environment. (ii) Population density: It is the number of individual organisms of the same species. Per unit area/volume of the habitat at a particular time. It determines the interaction between members of the same species and members of other species. It is mathematically expressed as Total population/population size. It is estimated in humans/animals by counting. In plants by using quadrat. Area of habitat (iii) Climax community: Is established when a stable/ unchanging community is attained in ecological succession. The community is in equilibrium with the environment. The vegetation reaches its highest development. The same species of animals, plants/organism re-occur from year to year. (b) Interaction between biotic and abiotic components of an ecosystem: In an ecosystem the abiotic factors are non-living things (carbondioxide, oxygen, sunlight, soil and water, etc) while the biotic components are plants and animals. Green plants use carbondioxide in the presence of sunlight to produce carbonhydrate/ starch/food. Animals/herbivores feed on carbonhydrate/ plants and release carbondioxide from respiration. Decomposers break down dead plants/animals/organic matters to release nutrients to the soil. These nutrients are absorbed by plants for use in food production/ photosynthesis. Plants give out oxygen during photosynthesis, which is used by animals for respiration.

(a) Inheritable characters: - Skin/hair/eye colour - Blood Group - voice Height/structure - Haemophilia Albino/albinism Weight Size - Sickle cell anaemia Colour blindness Size - Tongue rolling Intelligence - baldness (b)(i) Sites of Meiosis: - In plants: antheridium/archegonium. Anthers Ovary sporangium/spore capsule. In animals Testes Ovaries Mitosis Meiosis Nucleus divide only once Nucleus divides twice Number of chromosomes remain the same after division. Diploid Number of chromosomes is halved after division. Haploid Homologous chromosomes do not associate homologous chromosome associate to form bivalents chiasmata are never formed chiamata are formed crossing over never occurs / no exchange of genetic material crossing over occurs/exchange of genetic material occurs Daughter cells identical to parents cells daughter cell generally different from parent cell Two daughter cells are formed four daughter cells are formed chromosomes form single role at the equator chromosomes form double role at the equator Occurs in somatic cell occurs in reproductive cell occurs in asexual reproduction occurs in sexual reproduction The woman's claim is wrong. Reasons (ii) Half their children are heterozygous blood group A and Half homozygous blood group A (iii) No child is group 0.

(a)(i) Placentation: This is the arrangement of ovules, within the ovary. (b) (i) Organs Associated with human placenta: Umbilical cord, Uterus (b)(ii) Functions of Placenta: Establishes connection between the embryo and the mother. Carries oxygen/water/food/ nutrients from mother's blood to foetus. Removes waste/urea/salt/carbon dioxide from foetus blood to mother's blood for elimination. Produces progesterone/hormone for maintenance of uterine wall/ endometrium/pregnancy. Carries antibodies from mother's blood to foetus. (c) Viviparity: This is a type of reproduction in which the young develops inside the mother's body. Obtaining nutrients directly from the parent. When fully developed, the young are born alive. (ii) Territoriality: In many animal species individuals, usually males mark out areas/territories where they can live and breed. They guard these territories fiercely. Chasing away other members of the species. Only vigorous individuals are able to establish large territories, secure suitable mates and produce many offspring. Territoriality limits overcrowding. Animals that carry out this phenomenon are lizards, lions, etc. (iii) Seasonal migration: In many habitats food supply is affected by seasonal changes. Food is abundant in rainy seasons but scarce in dry seasons. Animals overcome these seasonal food shortages by moving to other habitats during unfavourable seasons. Such large scale seasonal movements of animals between habitats are called migrations. Other causes of migrations are temperature changes and breeding seasons.

(a)(i) Name of organism: A Domestic fowl/hen/cock/chicken. B Duck (ii) Habitats: A - terrestrial/land, B- Terrestrial/land. -Aquatic/fresh water/marine/sea/pond/lake/stream/river. (b) Adaptations to environment: Specimen A: - Presence of digits for walking on land. - Position of digits/three forward one backward/presence of class on digits. - For digging/searching/scratching for food/defense, - Presence of scales on foot to prevent desiccation/drying. Specimen B Webbed digits for swimming/paddling in water/ increases. - Surface area for walking on mud. - Presence of claws for digging for food. - Presence of scales on foot to prevent/protect against desiccation/drying/injury. (c)(i) Differences between specimens A and B A/Chicken foot : -digits free; -hind digit long B/Duck foot: -digits webbed; -hind digit short (ii) Similarities: Both specimens have scales - Presence of claws on digits. -Presence of three forward and one backward pointing digits. - Both have 4 digits each.

(a)(i) Agricultural classification: Classification of M and N: M/Bean seed - Legume N/Maize- Cereal (ii) Advantage of cultivation of M over cultivation of N: - Acts a cover plants to prevent erosion . Enriches the soil/conversion of atmospheric nitrogen to nitrates which are absorbed by the roots of the plants. (b)(i) Main classes of food: M/Bean - Protein N/Maize - Carbohydrate. (b)(ii) Functions: For body building/replacement /repair of worn out tissues. - For energy production (c)(i) State of M and N: Perforated/has holes/hollow, powdery. - Eaten/spoilt insects/infested. (ii) Pest: Weevil (iii) Phylum and Class with reasons: Phylum Reasons Anthropoda Segmented body Chitinous exoskeleton Jointed appendages Class Reasons Insecta Three body divisions/head, thorax and abdomen Three pairs of jointed legs. - Two pairs of wings (iv) Other crops; Rice, millet, guinea Corn, wheat. (d)(i) Adaptive Features of Pest: - Long proboscis/Rostrum. burrowing into the grain/feeding. - Hard forelimbs/elytron. -To protect hind/inner membranous wing/soft body. Small body size, - That will enable it For piercing/ penetrate/enter tne grain. - (Membranous) wings. for flying. (ii) Preventive measures: - Proper drying of grains. -Use of pesticides/insecticide. - Store in a dry place. - Use of irradiation. - Avoid mixing old stock of grains witn new grains. - Store in air light container. (e) Other pests: - Rats - Mice- Squirrel - Rabbit.

In \Delta TYX XY = TY ∴y =47^\circ base ∠s of ISC\Delta But y+x+34+47 = 180 interior opposite ∠s are supplementary 47 + x + 34 + 47 = 180 x + 128= 180 x = 180- 128 x = 52^\circ