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To evaluate \( 2M - 3N \) where \(M = \begin{pmatrix} 1 & 3 & 2 \\ 4 & 5 & -1 \\ -3 & 2 & 0 \end{pmatrix}\) and \(N = \begin{pmatrix} 1 & -2 & 3 \\ 4 & -1 & 5 \\ 2 & -3 & -1 \end{pmatrix}\) Calculate \( 2M \) \(2M = 2 \times \begin{pmatrix} 1 & 3 & 2 \\ 4 & 5 & -1 \\ -3 & 2 & 0 \end{pmatrix} = \begin{pmatrix} 2 \cdot 1 & 2 \cdot 3 & 2 \cdot 2 \\ 2 \cdot 4 & 2 \cdot 5 & 2 \cdot -1 \\ 2 \cdot -3 & 2 \cdot 2 & 2 \cdot 0 \end{pmatrix} = \begin{pmatrix} 2 & 6 & 4 \\ 8 & 10 & -2 \\ -6 & 4 & 0 \end{pmatrix}\) Calculate \( 3N \) \(3N = 3 \times \begin{pmatrix} 1 & -2 & 3 \\ 4 & -1 & 5 \\ 2 & -3 & -1 \end{pmatrix} = \begin{pmatrix} 3 \cdot 1 & 3 \cdot -2 & 3 \cdot 3 \\ 3 \cdot 4 & 3 \cdot -1 & 3 \cdot 5 \\ 3 \cdot 2 & 3 \cdot -3 & 3 \cdot -1 \end{pmatrix} = \begin{pmatrix} 3 & -6 & 9 \\ 12 & -3 & 15 \\ 6 & -9 & -3 \end{pmatrix}\) Calculate \( 2M - 3N \) \(2M - 3N = \begin{pmatrix} 2 & 6 & 4 \\ 8 & 10 & -2 \\ -6 & 4 & 0 \end{pmatrix} - \begin{pmatrix} 3 & -6 & 9 \\ 12 & -3 & 15 \\ 6 & -9 & -3 \end{pmatrix}\) Subtracting the matrices element-wise: \(= \begin{pmatrix} 2 - 3 & 6 - (-6) & 4 - 9 \\ 8 - 12 & 10 - (-3) & -2 - 15 \\ -6 - 6 & 4 - (-9) & 0 - (-3) \end{pmatrix}\) Calculating each element: \(= \begin{pmatrix} -1 & 12 & -5 \\ -4 & 13 & -17 \\ -12 & 13 & 3 \end{pmatrix}\) Final Result Thus, the result of \( 2M - 3N \) is \(\begin{pmatrix} -1 & 12 & -5 \\ -4 & 13 & -17 \\ -12 & 13 & 3 \end{pmatrix}\)

(a)(i) Habitat: Any environment within an ecosystem where an organism lives naturally. (1) Similar organisms tend to associate and live together (2) Every habitat is affected by some environmental factor(s) / biotic and abiotic factors (3) Habitats may be terrestrial e.g. Tropical rain forest/ grassland / Savanna/ desert/ any suitable example, or aquatic, e.g. ocean / lake pond, arboreal trunks / leaf surface / or any suitable example. (ii) Ecological Niche: Every organism is adapted to a specific place, and play a role in that community e.g. it feeds on some organisms/serves as food for others, it derives / obtains nutrients from its habitat! returns nutrients to it habitat, it is either a producer of a consumer. The sum total of all these roles for any given organism is referred to as its ecological niche. (b) List of Ecological instruments and their uses Instrument Uses (1) Light meter (2) Rain gauge (3) Anemometer (4) Wind vane (5) Secchi Disc (6) Soil Thermometer (7) Maximum and Minimum Thermometer (8) Barometer (9) pH of soil, paper / colorimeter (10) Hygrometer (11) Quadrant (12) Slope gauge (13) Metre rule/ tape measurement -for measuring light intensity -for measuring the amount of rainfall -for measuring the velocity /speed of the wind -for determining the direction of the wind -for measuring the turbidity / transparency of wind -for measuring soil temperature -for measuring atmospheric - temperature -for measuring the atmospheric pressure pH meter / pH -for determining the water or a medium -for determining the relative humid-ity of the atmosphere -for plant count. / to measure inclination or slope plumb line of land -for measuring distance / length. (c) Plants of the Savanna Region: Grass -Acacia, shea butter, date palm, Mosses, Silk cotton, Flambouyant, Baobab, Lophina, Mango, Epiphyte / Orchid, Mushroom, Crotalaria, Parkia clapertonia, Vitex etc. Animals of the Savanna Region Animal: Antelope, Elephant, Lion, Squirrel, Ants, Termites, Millipede, Centipede, Butterfly/ insects, Scorpions, snakes, Tortoise, Monkey, Baboon, Grasscutters, Giraffe, Zebra, Birds etc.

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

(a) Importance of transport systems in mammals are as follows: (i) The primary purpose of transport systems .is to move materials throughout the body of the organism (ii) Mammals have various substances/materials for specific functions located in different parts/organs of the body; For example oxygen is present in the lung while digested food is located in the alimentary canal (iii) Through transport systems metabolic waste products/excretory products are eliminated/removed via the kidney/lung/skin (iv) Hormones which are produced by the endocrine glands are made available to far away cells which they serve (v). Blood is the main medium of transport; assisted by the lymphatic system/lymph (vi)Mammals being large and complex organisms have a surface area comparatively smaller than the volume/surface volume ratio is low. Diffusion alone is inefficient (vii) Therefore there is the need to develop an efficient transport system to cope with this problem. (b) Functions of blood in mammals: (i) Blood serves as a transport medium of soluble organic compounds/digested food from the small intestines to various parts of the body where they are stored/assimilated or used; and transported from storage areas where they are used. (ii) It transports soluble excretory waste materials such as Urea/CO2/to organs of excretion such as kidney/lungs. (iii) Transport of hormones / from the glands/corresponding gland/where they are produced to target organs is also facilitated. (iv) Distribution of excess heat from deeply seated organs to maintain a constant body temperature is equally a function of the blood. (v) Transport of oxygen from the lungs to all parts of the body/transport of carbon dioxide produced by the tissues to the lungs. (vi) Defence against disease/foreign bodies through photocytosis. (vii) When an injury occurs, clotting of blood (by platelets/thrombocytes and fibrinogen) prevents excess loss of blood, and also prevents entry of pathogens/germs. (viii) Immunity is achieved by antibodies and lymphocytes carried by blood. (ix) Transports water (x) Transports mineral salts. (c) The following are materials transported in the bodies of flowering plants: (i) Latex/secretion/specific secretion (ii) Water/soil water (iii) Manufactured food / specific food e.g. glucose, amino acids (iv) Hormones/auxins (v) Dissolved mineral salts/specific salts e.g. nitrated, phosphate (vi) Oxygen (vii) Carbon dioxide. (viii) Excretory products

(a) Functions of the mammalian skeleton include: (I) Supports it posture and provides to the body e.g. backbones/ vertebrae/pelvic girdle (ii) It gives protection — e.g. ribcage protects heart/lungs/cranium(skull) protects brain/vertebrae protects spinal cord/pelvic girdle protects female reproductive organs. (iii) The skeleton helps in the production of blood cells — in the bone/marrow of the long bones (iv) Storage of calcium is also encourage, e.g., in the bone matrix (v) Movement/locomotion is enhanced. — any of the limb bones (vi) Breathing movements — Riles (vii) Attachment of muscles is facilitated — any bone (viii) Provision of shape-axial skeleton/grindles etc (b) Bones and muscles bring about movement at the elbow in the following ways: (i) Bicep and tricep act antagonistically to bring about movement at the elbow. The bicep is attached to the scapula and radius; while the tricep are attached to the scapula and ulna (ii) Bicep contracts while tricep relaxes to cause bending/flexing of the forearm (iii) Tricep contracts while bicep relaxes to cause straightening of the forearm. (c) Support in herbaceous and woody Plants can come in different ways: (i) Herbaceous Plant: (1) By turgidity, water is preserved (2) Due to the presence of water, vacuoles inside parenchyma cells/living cells (3) Thickening of walls of collenchyma cell (at the corners). (ii) Woody Plant: (1) Sclerenchyma in the cortex (2) By the Xylem strengthened by deposits of lignin in their walls (2) Secondary growth/thickening provides extensive wood / secondary xylem and bark. (d) The vitamin and mineral element necessary for healthy bone development are: (1) Vitamin — D/Calciferol, Vitamin C (forms the cement of bow) (2) Mineral elements — calcium/phosphorus/magnesium.

(a) Definition of enzymes: Enzymes are organic catalyst substance that speed up/slow down the rate of biochemical reactions, they are made of proteins, and produced by living cells. (b) Characteristics of enzymes are: (1) Remain chemically unchanged at the end of a reaction (2) Are specific in action/one or a group of enzymes will act on specific substrates (3) Required in small quantities (4) Act best over a specific range of temperature/between 35o — 40^\circC (5) They are denature/destroyed at high temperature/inactivated at very low temperature (6) Act best at specific Ph (either acidic or alkaline) (7) Their action is reversible (8) Enzyme action is retarded by poison or inhibitors (9) Some are inactive and require a co-enzyme/agent to activate them (10) They can function outside the body of the organism that produces them (11) Enzymes are protein in nature (c) Role of Pancreatic juice in carbohydrate and Protein digestion are: (1) Pancreatic juice provides an alkaline medium for the action of the enzymes involved; Which operate in the small intestine/duodenum (2) Pancreatic juice contains Amylase/Amylopsin, which converts starch to maltose sugar, it also contains trypsin, which converts proteins to peptone / peptide/ polypeptides /amino acids (3) Carboxypeptidase, converts polypeptides to amino acids. (d) Storage of excess carbohydrate takes this form: (i) In Animals : Glycogen /fat (ii) In plants: Starch /Sucrose/ Sugar (e) The saprophytic nutrition of reproduction goes like this: - Rhizopus grows on organic matter e.g. damp/moist food/ bread / decaying mater substrate; its hyphae penetrate the food / substrate and secrete hydrolyzing enzymes, Which digest the food / substrate / results in extracellular digestion; the hyphae absorb the digested food / soluble products for metabolic activity.

(a)(i) Definition of asexual reproduction: Asexual reproduction is the production of a new individual from a parent / organism / order individual, without fertilization / gametes / change in chromosome number/genetic constitution; it involves, a single parent. (ii) Types of asexual reproduction in animals Types Example; Types Example (1) Binary fission (2) Budding (3) Sporulation (4) Parthenogenesis (5) Schizogony (6) Fragmentation Amoeba, Paramecium Hydra/Obelia Amoeba Aphids, Honey bee Plasmodium / Merozoides Planaria / Sponges / Hydroid Coelenterate (b) Differences between asexual and sexual reproduction Asexual reproduction Asexual reproduction Sexual reproduction (1) One parent involved (2) No gametes formed (3) Meiosis not involved (4) No fertilization / fusion of gametes/ sex cell / no zygote formed (5) Offspring identical I. No genetic variation (6) Rapid / faster mode of reproduction (7) More individuals are produced Two parents involved Gametes / sex cells formed meiosis involved Fertilization / fusion of gametes / sex cells occur zygote formed Offspring vary genetically Slower mode of reproduction Fewer individual are produced (c) (d) Function of organelles; Acrosome - contains enzymes / lytic agents that help to digest the cell membrane of the female ovum during fertilization. Nucleus; contains haploid number of chromosomes / genetic materials / DNA Mitochondria; contain respiratory enzymes / for respiration that provide energy / site for production of energy for locomotion/ movement.

(a)(1) Trait: Characteristic of an organism controlled by pairs of genes. (ii) Recessive gene: Member of a pair of genes in a genotype, whose characteristics are not manifest in the phenotype / in the presence of its contrasting gene / allele (iii) Test cross: Mating / exposing of the heterozygous individual of Fl generation, to homozygous recessive parents (iv) Heterozygous: This refers to the genotype, consisting of two different / contrasting genes / alleles Blood group of Blood Blood Blood Blood Offspring Group A Group B Group A Group A No, the man cannot be-the father of the child. (c)(i) Test cross: The male rabbit (Brown) is mated with a homozygous white female rabbit, having the recessive trait, f the male is homozygous all the offspring will be brown, if the male is heterozygous half of the offspring will be brown and half white. (ii) Gamete and somatic chromosome number: The gametes contain half the number of chromosomes / n / haploid number of chromosomes, found in the body / somatic diploid / 2n cell.

Length of an arc = \(\frac{\theta}{360}\) x 2\(\pi\)r 22 = \(\frac{3x}{360}\) x \(\frac{22}{7}\) x 7 (since D = 2r) 22 x 7 x 360 = 3x X 22 X 7 x = \(\frac{22 \times 7 \times 360}{3 \times 22 \times 7\times 2}\) = 60º

PQ = \(\sqrt{(\beta - 1)^{2} + (1 - \alpha)^{2}}\) 3 = \(\sqrt{(\beta^{2} -2\beta^{2} + 1 + 1 - 2\alpha + \alpha^{2})}\) 3 = \(\sqrt{(\alpha^{2} + \beta^{2} - 2\alpha + 2\beta + 2)}\) 3 = \(\sqrt{(\alpha^{2} + \beta^{2} - 2(\alpha + \beta) + 2)}\) 3 = \(\sqrt{(\alpha^{2} + \beta^{2} - 2 * 2 + 2)}\) 3 = \(\sqrt{(\alpha^{2} + \beta^{2} - 2)}\) 9 = \(\alpha^{2} + \beta^{2} - 2)\) \(\alpha^{2} + \beta^{2}\) = 9 + 2 \(\alpha^{2} + \beta^{2}\) = 11

6x + 6y = (n - 2) 180 6x + 6y= (5 - 2) 180 6(x + y) = 3 * 180 x + y = (3 * 180)/6 x + y = 90o y = 90 - x

Area of parallelogram PQTU = base * height 32 = 4 * h w = 32/4 w = 8 ∴ = Area of Trapezium PQRU = (1/2)(4 + 14) *8 = 1/2 * (18 * 8) = 72 cm\(^2\)

Mid point = \(\frac{(x_1 + x_2)}{2}\) ; \(\frac{(y_1 + y_2)}{2}\) = \(\frac{(-3 + 5)}{2} ; \frac{(5 - 3)}{2}\) = \(\frac{2}{2}\) ; \(\frac{2}{2}\) = (1, 1)

The diagonal QS bisects the angle formed by PQ and QR ∴ [A]

\(\frac{X}{\sin 45^\circ} = \frac{15}{\sin 60^\circ}\) \(X = \frac{15 \sin 45^\circ}{\sin 60^\circ}\) \(X = \frac{15 \times \left( \frac{1}{\sqrt{2}} \right)}{\sqrt{\frac{3}{2}}}\) \(X = \frac{15}{\sqrt{2}} \times \frac{2}{\sqrt{3}}\) \(X = \frac{30}{\sqrt{6}}\) \(X = \frac{30}{\sqrt{6}} \times \frac{\sqrt{6}}{\sqrt{6}} = \frac{30\sqrt{6}}{6} = 5\sqrt{6}\)