(i) Forelimbs of cheetah and mammals
(ii) Forelimbs of whales and mammals All these animals show similarities in Pattern of bones of forelimb but they perform different functions. They have similar anatomical structure. Hence, the same structural organs in these animals have developed in different directions because of adaptations to their different requirements. This shows thus the divergent evolution & that the structures/organs are homologous.

Homo habilis where first human like homind. They probably did not eat meat/vegetarian, and their brain capacities were between 650-800cc.

The differences between unambiguous and universal genetic codes are as follows

(ii) The differences between degenerate and initiator codes are as follows

Typhoid.
1.it is an infectious disease caused by bacteria,Salmonella typhi.
2.The infection is by contaminated food and water.
3.The pathogen enters the small intestine and then the other parts through body fluids.
4.Its symptoms include:(a) sustained high fever (\({ 103 }^{ 0 }-{ 104 }^{ 0 }\) F),(b)stomach pain,(c)loss of appetite, (d) constipation and (e)headache.
5.Intestinal perforation leading to death in severe cases.
6.Typhoid can be confirmed by Widal test.

a - Small intestine.
b - Rhino viruses
c - Nose,respiratory passage
d - Alveoil of lungs

The two types of immune responses are.
(i) Primary immune response 
(ii) The immune response that occurs as a result of the first encounter of the animal with an antigen is called primary immune response.
(iii) It takes longer time to establish immunity.
(iv) It declines rapidly.
(d) Secondary immune response
(i) The immune response that occurs at the second and subsequent encounters of the animal with the antigen,is called secondary immune response.
(ii) It is more rapid and results in hightened immunity.
(iii) It lasts for longer periods.

(i) The methylated guanosine cap helps in the binding of mRNA to the smaller subunit of ribosome during initiation of translation.
(ii) Poly-A tail has a direct relatioship with the logevity of mRNA.

Industrial melanism is an example of Darwin's theory of natural selection. Before industrial revolution in England the environment was unpolluted. The lichens on the barks of trees were pale. The white-winged moths could easily camouflage, while the dark winged were spotted out by the birds for food. Hence, they could not survive. After industrial revolution the lichens became dark disappeared (due to pollution and soot deposit). This favoured the dark-winged moths while the white-winged were picked by birds. The population of the former which was naturally selected increased This shows that in a mixed population those which can adapt in abetter way with the changing environment survive and increase in population, Thus industrial melanism in this way supports Darwin's theory of natural selection.

(i) Parallel evolution.
(ii) Convergent evolution.
(ii) Divergent evolution.

(i) b (ii) c, e and g (iii) a (iv) f (v) d.

(a) A part of the life cycle of the parasite occurs in the body of female Anopheles mosquito; these mosquitoes act as vectors and transmit the disease from patients to healthy individuals.
(b) Fertilisation; it occurs in the intestinal wall of mosquito.
(c) Salivary gland. Sporozoites are the cells released from it.

(i) Typhoid,Polio,Amoebiasis.
(ii) Filariasis,Malaria.
(iii) Pneumonia,common cold.

Each antibody molecule has four polypeptide chains.

Of them,two are small and called light chains (L) and two of them are longer and called heavy chains(H) hence written as  H₂ L₂.

(a) Amoebiasis is caused by Entamoeba histolytica.
(b) Symptoms:
(i) Constipation 
(ii) Abdominal cramps and pain.
(iii) Stool with excess mucus and blood clots.
Transmission 
Drinking water and food contaminated with the faeces of infected persons.
Houseflies act as mechanical carriers and transmit the parasite from faeces to food and water.

The lac operon consists of
(i) three structural genes (z,y and a) which code for \(\beta \) -galactosidase, permease and transacetylase, respectively.
(ii) an operator; which controls the structural genes as a unit.
(iii) a regulatory gene ti.e., inhibitor gene) and
(iv) a promoter, where the RNA polymerase binds for transcription.
The regulatory gene codes for the repressor protein, all the time (constitutively): the repressor binds to the operator to inactivate the operon.
 Lactose enters the cell with the help of permease and the active form of lactose binds to the repressor and prevents it from binding to the operator.
This allows RNA polymerase an access to the promoter and transcription continues, i.e. lac operon is activated.

(i) The students repeated the experiment performed by Oswald Avery, Colin |MacLeod and Maclyn McCarty (1933-44), who worked to determine the biochemical nature of 'transforming principle' in Griffith's experiment.
(iii) Frederick Griffith in 1928 performed the transformation experiment.
(iv) Scientific attitude, awareness and love for animals and respect towards government policies.

Divergent evolution involves the differences in apearance and functioning of those structures which are similar in their basic structural plan and similar developmental origin e.g. force limbs of vertebrates like seal, bird, cat's paw, horse and man look different and perform different functions as shown in the table.

They have same pentadactyl plan and similar arrangement of bones, blood vessels, nerves, ect., This confirms that forelimbs have undergone divergent evolution, but are homologous to one another.
Driving force for divergent evolution is adaptive radiation to perform different functions