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(a) Definition of tropic and nastic movements: (i) Tropic movement is growth movement of plant organs in response to external unilateral or directional stimulus. Nastic movement is the movement of certain parts of plants in response to diffuse or non-directional stimulus. (ii) Tropic movement Nastic movement Movement is not easily reversible. Response leads to growth. Movements are not due to change in cell turgor. Response is towards the direction of the stimulus. Response is slow. Responses are not due to pressure. Movement is reversible. Response does not lead to growth. Movements are due to changes in cell turgor. Response is not Directed to the stimulus. Response is rapid. Responses are due to pressure. Experiment to show that auxins are produced in the apical cells of a shoot: Aim: To show that auxins are produced in the apical cells of a shoot. Material: 3 potted seedlings of maize labelled A, B and C; agar block, sharp knife/cutting instruments, mica sheet / aluminium foil/cover slip. Methods: (i) Cut tip of coleoptile/shoot in Ato serve as control (ii) Leave decapitated shoot for about 48 hours (iii) Select another potted seedling, B,.and cut off tip of coleoptile/shoot (iv) Place the cut tip on an agar block for about 2 — 6 hours (v) Place agar block on stump of the decapitated shoot and leave for about 48 hours (vi) Select a third seedling, C, and cut off tip of the coleoptile (vii) Place tip of the cut coleoptile on mica sheet for 2 — 6 hours (viii)Place mica sheet on cut surface of decapitated shoot and leave for about 48 hours. Observation: Growth ceased in decapitated shoot A, but when agar block was placed on stump of shoot B in which growth had stopped, growth resumed. When mica sheet was placed on stump of shoot C in which growth had stopped, growth did not take place (resume). Conclusion: This shows that a chemical substance (auxin) produced at the tip, i.e., apical cell of the shoot is responsible for the growth of the shoot. (c)(i) Names of plant hormones other than auxins are Gibberellic acid / Gibberellin 2, 4 - D 2, 4 - Dichlorophenozy acid cytokinis/kinins/kinetin abscisic acid/abscisin ethylene/ethene traumatin florigen dormin formin, etc. (ii) Examples of tropisms are: geotropism hydrotropism thigmotropism/Haptrodropism photoropism stereotropism chemotropism thermotropism.

(a) An ecosystem; is a natural unit in which there is an interaction between all living organisms (biotic factors) and non-living organisms (abiotic factors) within an environment or habitat. (b) Abiotic factors that affect plants and animals are: inorganic compounds or elements, e.g. O\(_2\), N\(_2\), salts, CO\(_2\) , H\(_2\)O etc; water/rainfall; temperature; light/ sunlight; wind; altitude; pressure; moisture/humidity; pH; wildfire/thunder and lightning (c) Effects of abiotic factors include: (i) Temperature: (1) high temperature leads to high transpiration rate in plants/ aestivation and hibernation in animals (2) High rate of metabolism in organisms (3) a high rate of decay of organic matter (4) a higher rate of growth and shorter length of life cycle in some organisms, e.g. housefly and toad (5) at very low temperature plant roots absorb water at slower rates leading to reduction in the rate of transpiration and metabolism of organisms (6) at low temperature, animals, e.g. snails may hibernate., birds migrate. (ii) Rainfall: (1) makes water available to organisms (plants and animals) (2) quantity of rainfall determines type of vegetation in a habitat (3) vegetation in turn influences types of animals that will live there (4) rainfall, splash or floods may dislodge organisms (5) rainfall increases relative humidity which may affect the rate of transpiration and perspiration in plants and animals respectively (6) rainfall causes soil erosion which deprives plants of soil nutrients (7) may form puddles or ponds thereby creating habitats or breeding ground for certain terrestrial organisms (iii) Wind: (1) steady wind increases rate of evaporation, transpiration and desiccation for animals (2) strong wind causes soil erosion which affects living organisms (3) strong wind breaks off branches of trees, fell trees or bend them, and force animals out of cover (4) aids dispersal of organisms (5) aids pollination (iv) Light: (1) intensity of sunlight affects plants by affecting rate of photosynthesis (2) affects the rate of transpiration and stomata opening (3) adequate sunlight promotes growth of many plant species (4) low light leads to growth of shade tolerant species (5) light affects the vision/movement of animals (6) light affects the distribution of organisms in habitat. (v) Pressure/Altitude: (1) at high altitude, pressure decreases and animals have problems with respiration and blood pressure (2) at high altitude, temperatures decrease while wind action increases, and this affects the distribution of organisms (3) at high altitudes, only animals with special hemoglobin are found in the environment (4) altitude may affect speciation (5) altitude may affect the behavioral pattern of animals. (vi) Inorganic Compounds: (1) used by organisms (plants and animals) to maintain growth and sustain life (2) 02 for respiration (3) CO2 for photosynthesis (4) N2/Nitrates promote plant growth (5) H2O for growth and maintenance of body temperature (6) PO for protein synthesis (7) SO4\(_2\) for plant growth. (vii) Humidity: (1) affects rate of transpiration and perspiration (2) affects the vision of animals through the formation of fog or mist (3) affects the activities of poikilothermic animals (4) affects the distribution of organisms, e.g. earthworms; bryophytes, e.g. liverworts etc. (viii)Wildfire/Thunder and Lightning: (1) destroys organisms, vegetation and animals (2) displaces organisms (animals) from their habitat

P = {1,2,u,v,w,x} Q = {2,3,u,v,w,5,6,y} R = {2,3,4,v,x,y} P - Q = {1,x} (P - Q) ∩ R = {1,x} ∩ {2,3,4,v,x,y} = {x} NB: The set P−Q consists of elements that are in P but not in Q.

1st year, Population = 240,000 x (\(\frac{2}{100}\)) = 4800. Being the 2nd year population = 240,000 + 4800 = 244800. Increase in Pop. in 2nd year = 244800 x (\(\frac{2}{100}\)) = 4896 Jan 2000, Pop. = 244800 + 4896 = 249,696

Rationalize \(\frac{(2\sqrt{3}-\sqrt{2})}{(\sqrt{3}+2\sqrt{2})}\) and equate to \(m +n\sqrt{6}\). Such that m = -2, and n = 1. Use \(\sqrt{3}-2\sqrt{2}\) as the conjugate for Rationalization \(\frac{(2\sqrt{3}-\sqrt{2})}{(\sqrt{3}+2\sqrt{2})}\) X \(\frac{(\sqrt{3}-2\sqrt{2})}{(\sqrt{3}-2\sqrt{2})}\) \(\frac{6 - 4\sqrt{6} - \sqrt{6} + 4}{3 - 2\sqrt{6} + 2\sqrt{6} - 8}\) =\(\frac{10 - 5\sqrt{6}}{-5}\) = -2 + \(\sqrt{6}\) = \(m +n\sqrt{6}\) ∴ m = -2 and n = 1

x = no. of ppl that like none. no. of ppl that like both Traditional and Modern music, which is equal to 3x Modern Music = 60 - 3x Traditional Music = 50 - 3x 60-3x + 50 - 3x + 3x + x = 94 110 - 3x + x = 94 -2x = 94 - 110 =>-2x = -16, this x = 8. Members that like only one music: = 60 - 3x + 50 - 3x = 60 - 3[8] + 50 - 3[8] = 60 - 24 + 50 - 24 = 36 + 26 = 62 Members that like only one type of music = 62

\(\frac{2.813 \times 10^{-3} \times 1.063}{5.637 \times 10^{-2}}\) = \(\frac{0.002813 \times 1.063}{0.05637}\) \(\approxeq \frac{0.0028 \times 1.1}{0.056}\) = \(0.055\)

Amount A = P(1+r)n; A = N150,000, r = 25%, n = 3. 150,000 = P(1+0.25)3 = P(1.25)3 P = 150,000/1.253 =N76,800.00

\(314_{10} - 256_7 = 340_x\) Convert 2567 and 340x to base 10, such that: 314 - 139 = 3x\(^2\) + 4x => \(3x^2\) + 4x - 175 = 0 (quadratic) Factorising, (x - 7) (3x + 25) = 0, either x = 7 or x = -25/3 ( but x cannot be negative) Therefore, x = 7.

Start by expanding \(\frac{3(2^{n+1}) - 4(2^{n-1})}{2^{n+1} - 2^n}\): \(\frac{3 \times 2^n \times 2^1 - 2^2 \times 2^n \times 2^{-1}}{2^n \times 2 - 2^n}\) NUMERATOR : 2\(^n\) ( 3\(^1\) X 2\(^1\) - 2\(^2\) X 2\(^{-1}\) ) --> 2\(^n\) ( 3 X 2 — 4 X \(\frac{1}{2}\) ) --> 2\(^n\) ( 6 - 2 ) --> 2\(^n\) (4) DENOMINATOR : 2\(^n\) ( 2\(^1\) - 1 ) --> 2\(^n\) ( 2 - 1) --> 2\(^n\) => \(\frac{2^n ( 4)}{2^n}\) = 4

Convert everything to base 10 and collect like terms, such that \(210P - 42P = 434 + 406\) \(168P = 840\) \(P = 840/168 = 5\)

Fresh water is less dense than the salt water, hence when the ship sails in fresh water, it will sink more, thus the fraction of the ship above the water surface will decrease.

The acceleration is not constant, i.e. its direction changes although the magnitude is constant (III is wrong), another thing that makes III wrong is the fact that the acceleration is not directed away from the centre but towards the centre. - No work is done on a body undergoing circular motion - Note that when a body is undergoing circular motion ], its velocity is not constant, i.e. the direction changes, although the magnitude is constant. - Since the acceleration is directed towards the centre, the centripetal force is directed towards the centre.

Efficiency = \(\frac{\text{M.A}}{\text{V.R}}\) 75% = \(\frac{\text{M.A}}{\text{V.R}}\) \(\frac{75}{100} = \frac{\text{M.A}}{5}\) M.A = \(\frac{75(5)}{100}\) = 3.75 But M.A = \(\frac{\text{Load}}{\text{Effort}}\) 3.75 = \(\frac{150}{\text{Effort}}\) Effort = \(\frac{150}{3.75}\) Effort = 40N

a * b = a\(^b\) a * 2 = a\(^2\) = 2 - a a\(^2\) + a - 2 = 0 a\(^2\) + 2a - a - 2 = 0 a(a+2) - 1(a+2) = 0 (a-1)(a+2) = 0 a = 1, -2