1. Baculoviruses belong to NucIeopolyhedroviruses. They are used as biocontrol agents and preferred over radilly available chemical pesticides because they are species specific and have narrow spectrum insecticidal application. They do not harm the non
target organisms.
2. Bacillus thuringiensis is a bacterium and is a biocontrol agent against cotton bollworm insects.
3. They produce a toxin that specifically kill the insect larvae when the toxin is released in their gut. It is also preferred over chemical pesticides' because it is specific and does not have negative role over non target organisms. More over the biopesticides are inexpensive and do not cause environmental pollution.

(a)Parasites have evolved the following adaptations.
(i) Loss of unnecessary sense organs.
(ii) Presence of hook/adhesive organs and suckers.
(iii) Loss of digestive system .
(iv) High reproductive capacity
(b) In some cases, a parasitic species may evolve with its host taxa. Long-term co-evolution sometimes leads to a relatively stable relationship, tending to commensalism or mutualism, as it is in the evolutionary interest of the parasite that its host thrives. A parasite may evolve to become less harmful for its host or a host may evolve to cope with the unavoidable presence of a parasite, co the point that the parasite's absence causes the host harm

(i) (a) Species  A group of specific organisms with similar characteristics which are capable of compatible interbreeding to produce fertile offsprings
(b) Niche The way in which an organism functions in relation to the biotic and abiotic factors within its habitat that serves a purpose in its environment.
(ii) Increased selection pressure due to climatic or habitat change cause organisms to become specialised and have the optimum phenotype that is suited to the prevailing environment condition.
In the primary radiation, the six closely related species evolved as a result of the increasing water levels when the lake first filled. This change in the environment exerted a selection pressure on their river dwelling ancestors to adapt by developing different characteristics for survival, thus giving rise to the six species that could occupy more niches.

(a) Protocooperation
(b) Mutualism
(c) Mutualism
(d) Parasitism

(a) Gelatin (b) Agar agar
(c) Nutrients like inorganic salts, vitamins, 2-4% sucrose, amino acid glycine and growth regulators.

(i) Both the terms refer to large scale changes in sea-surface temperature across the central and eastern tropical Pacific. Usually, sea-surface temperature, off South America's west coast, ranges from \({ 60 }^{ 0 }F\) to \({ 70 }^{ 0 }F\) , while it exceeds \({ 80 }^{ 0 }F\) inthe "warmpool" located in the central and western Pacific. This warm pool expands to cover the tropics during E1-Nine but shrinks to the west during La-Nino.
(ii) Increase in release of green house gases  (CO₂ and methane) are responsible for increase in temperature. Thus leads to global warming.

(i) Wheat - Roti
(ii) Rice - Idli and Dosa
(iii) Bengal gram - Dhokla and khandvi.

a) Inbreeding depression can be overcome by outcrossing.
(b) (i) Inbreeding is necessary to evolve purelines in any animal, as it increases homozygosity.
(ii) Inbreeding exposes the harmful recessive alleles, which become eliminated by selection.
(iii) It helps in accumulation of superior genes and elimination of the less desirable ones.
(c)Hisardale, a breed of sheep.

Different characters of population, methods to control birth

(i) River eutrophicated due to run off water from field containing non- biodegradable chemicals like fertilizers containing Nitrogen / Phosphorus .Water becomes nutrient- rich . A large algal bloom is formed.
(ii) Do deplete fish will die.
(iii) No

1. Single cell protein-Microbes like spirulina can be gown easily on materials like waste water from potato processing plants, molasses, animal manure, even sewage in large quantities & serve as food as it is rich in nutrients & specially proteins (microbial components).
2. 250g of microbe Methylophilus methylotrophus can yield 25 tones of proteins.

(a) Chlorofluorocarbon. 
(b) CFC move upward and reach stratosphere UV-rays act on them releasing CI atom due to which ozone degrades releasing molecular oxygen.

Higher biological oxygen demand shows that the dissolved oxygen in water bodies is much reduced and thus aquatic animals will die.0.

Thorns and spines are the most common morphological defence, e.g. Citrus and Duranta have thorns, Acacia and Zizyphus have spines.

(a) Age pyramid:
(b) Age distribution depends upon the natality and mortality and determines the population growth. With regard to age distribution, there are three kinds of population .
1.Rapidly growing or expanding population: It has high birth rate and Jaw death rate, so there are more number of young individuals in the population. According to a recent survey, more than 36% of the Indian population consists of children below the age of 14 years, so the Indian population is called young population.

2. Stationary or stable population: It has equal birth and death rates, so the population shows zero population growth.

3. Declining population: It has higher death rate than birth rate, so the population of young members is lower than that of old members, e.g., Japan (ageing population).

(i) E-waste is electronic products nearing the end of their useful life. It includes computers, monitors, CDs, DVDs, VCRs, televisions, mobiles, laptops, games, etc.
It causes toxicity due to some of the substances.
(ii) Uncontrolled burning and disposal of e-waste is causing environment problems.

(i) Aerobic microbes
The primary effluent is passed into large aeration tanks where it is constantly agitated mechanically and air is pumped into it. This allows vigorous growth of useful aerobic microbes into flocs (masses of bacteria associated with fungal filaments to form mesh like structures). While growing, these microbes consume the major part of the organic matter in the effluent. This significantly reduces the BOD (biochemical oxygen demand) of the effluent. The sewage water is treated till the BOD is reduced. Once the BOD of sewage or waste water is reduced significantly, the effluent is then passed into a settling tank where the bacterial 'flocs' are allowed to sediment.
ii). This sediment is called activated sludge. A small part of the activated sludge is pumped back into the aeration tank to serve as the inoculum. The remaining major part of the sludge is pumped into large tanks called anaerobic sludge digesters. Here, other kinds of bacteria, which grow anaerobically, digest the bacteria and the fungi in the sludge. During this digestion, bacteria produce a mixture of gases such as methane, hydrogen sulphide and carbon dioxide. These gases form biogas and can be used as source of energy as it is inflammable. The effluent from the secondary treatment plant is generally released into natural water bodies like rivers and streams.

(a) Tissue culture / micro propagation.
Explants, grown in a test-tube, under sterile condition, in special nutrient medium / culture medium. For detailed refer to Question No. l. (L.A.T.Q.)PP 246.
(b) Isolated single cells, digests cell walls, to obtain naked protoplast from two different varieties, fusion of protoplast.
Hybrid protoplasts thus, obtained are cultured in a suitable medium to form new plants.