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(a) Castes found in termites are Queen, King, Soldiers, Workers, Winged reproductive (b) (I) Role of each caste: (1) Queen produces eggs/ egg laying/reproduction (2) King fertilizes the eggs through mating with the queen (3) Workers build/repair the termitarium/ the colony, search for/ store/collect /digest food, collect eggs, feed the nymphs/queen when too aged/necessary; clean the colony (4) Soldiers protect the colony from enemies / defend the colony. (5) Winged reproductive can become the future queen/future king or initiates a colony. (ii) The economic importance of termites to man include: (1) Destruction of crops, wood, furniture etc. (2) Improves aeration of soil (3) Edible/source of protein and revenue earning (4) Helps to speed up decay processes and add manure to increase soil fertility. (c)(i) Types of courtship behaviour in lower animals are: Dancing, Display, Singing/ croaking, Pairing, Nest-making, Seasonal migration, Territoriality, Production of odour by female to attract the male, Symbolic feeding of the female to attract the male. (c) (ii) The importance of courtship behaviour in lower animals are: (1) Prepares male and female for possible mating/pairing (ii) Stimulates egg-laying and sperm release in the partners (3) Enhances fertilization/reproduction. (d) During courtship, the male Agama lizard establishes a territory and guards it from other males. The male displays its full colour which the female is attracted to and responds by assuming a soliciting posture by arching her back or bending down while lifting her tail up vertically.The male chases the female into the territory and grips her by the neck.

(a)Organic evolution is a sum total of adaptive changes from pre-existing or old forms which have taken place over a long time and which result in diversity of form, structure, and functions among organisms. (b) (i) Larmack contributed greatly to organic evolution as he brought great changes in environment resulting 'in a corresponding changes in the species. These changes cause the organism to form new structures or habits to adjust to the new or prevailing environment. The organism then develop specialised characters by use and dis-use of organs which when frequently used become well developed while the ones not used degenerate and become atrophied/useless/vestigial. The well developed or dominant acquired characters are inheritable. (ii) Darwin in his contribution to organic evolution postulated that species have abilities to produce large number of offspring into the environment with limited resources, thus leading to competition by these offspring. The survivors which must have inherited the useful traits then reproduce and pass on these good traits to their offspring. Those that could not survive the struggle die off or are eliminated. This phenomenon is often referred to as the survival of the fittest/natural selection. There is great variability with population as this process continues through many generations while the population gradually becomes better adapted to the environment. This gives rise to the origin of new species. (c) Evidences of organic evolution are: (i) Geological /fossil records/palaeontology/archeological/ historical records, (ii) Geographical distribution (iii) Comparative anatomy/ structure (iv) Embryology (v) Vestigial organs (vi) mesticated organism. (d) (I) Mutation brings about sudden appearance of distinct trait or character in large population of organism due to minor change or alteration in the gene or chromosome. Mutation can only be inherited when it occurs in the gene or gametes leading to production and perpetuation of new species. Mutation elsewhere in the body can not be passed on or inherited. (ii) The role of isolation in the formation of new species is that if members of a specie are separated into two or more populations by natural barriers like desert, mountains, oceans, rivers, continental drift, etc for a long period, their genes may change to the extent that they cannot interbreed again to produce viable offspring; and the population thereby may have produced new species.

(64.764 - 35.236)(64.764 + 35.236) = 29.528 x 100 = 2950 to 3 sig. fig.

\(\frac{2}{x} - {\frac{3}{y}}\) = 2.....(1) \(\frac{4}{x} + {\frac{3}{y}}\) = 10 ... (2) (1) + (2): \(\frac{6}{x}\) = 12 \(\to\) x = \(\frac{6}{12}\) x = \(\frac{1}{2}\) put x = \(\frac{1}{2}\) in equation (i) = 4 - \(\frac{3}{y}\) = 2 = 4 - 2 = \(\frac{3}{y}\) therefore y = \(\frac{3}{2}\)

t = \sqrtpq/r - r\(^2\)q multiply both sides by the L.C.M, r r\(^2\) = pq - qr\(^3\) collect like terms on the RHS q(p - r3) = rt\(^2\) q = \(\frac{rt^2}{(p - r^3)}\)

\(\alpha= \frac{\Delta{L}}{L_1\Delta\theta}; \Delta{L}=\alpha{L_1}\Delta\theta\Rightarrow 1.0\times 10^{-5}\times 300\times (40-28)= 0.036 or 3.6\times 10^{-2}\)

An object falling without air resistance or friction is defined to be in free-fall. The acceleration of free-falling objects is therefore called the acceleration due to gravity. It is because the acceleration due to gravity is constant for all objects regardless of the mass, neglecting air resistance.

\( \theta _3 \) shows the angle of deviation

Examples of transverse waves include: ripples on the surface of water. vibrations in a guitar string. a Mexican wave in a sports stadium. electromagnetic waves – eg light waves, microwaves, radio waves. Some basic properties of light : Reflection of light. Refraction of light. Diffraction of light. All kinds of waves have the same fundamental properties of reflection, refraction, diffraction and interference, and all waves have a wavelength, frequency, speed and amplitude.

The absolute pressure exerted by a given mass of an ideal gas is inversely proportional to the volume it occupies if the temperature and amount of gas remain

There are several methods of preparation of acids. These include the following: 1. By the reaction between an acidic oxide of a non-metal (acid anhydride) and water. SO2(g) + H2O(l) → H2SO3(aq) Trioxosulphate(IV) P4010(s) + 2H2O(l) → 4HPO3(aq) Trioxophosphate(V)

Now in permanent hardness of water, when washing soda is treated with water, the carbonate ions from sodium carbonate react with calcium and magnesium ions in water and produce an insoluble product. Therefore, calcium carbonate is precipitated out.

0.0425/2.5 = 425/25000 = 17/1000

P ∩ Q = {5, 6}

Let x represent the intersection 34 - x + 22 - x + x = 49   - x = 49 - 56; x = 7