The major problem here is that the proteins with a short half lives are not orally active and are not absorbed properly.
An orally active protein should be metabolically stable and have a longer half life, so that it is not degraded fast and absorbed efficiently.
To make orally active protein drug, the site directed mutagenesis can be used to redesign their genes for the expression of a modified peptide.

Offsprings formed by sexual reproduction have better chance of survival due to the genetic variability . Sexual reproduction involves fusion of male and female gametes.As a result of this fusion (combination of DNA from two individuals of a species), new variants are formed. these variants can adapt to varied environmental conditions and thus, provide better chances of survival to the organism.Thus this statement is always true.

Since, DNA is a hydrophilic molecule, it cannot pass through the cell membranes. In order to force bacteria to take up the plasmid, the bacterial cells must first be made competent to take up DNA. This is done by treating them with a specific concentration of a divalent cation such as calcium, which increases the efficiency with which DNA enters the bacterium through the pores in its cell wall.
Recombinant DNA can then be forced into such cells by incubating the cells with recombinant DNA on ice, followed by placing them briefly at 42 C (heat shock) , and then putting them back on ice. This enable the bacteria to take up the recombinant DNA.

Three uses of PCR are:
(i) It is used to during rDNA for production of newer and desired DNA
(ii) It is used for DNA sequencing.
(iii) It is used in DNA figerprinting.

A - GnRH
B - FSH
C - Spermatogenesis
D - Spermiogenesis

The creation and the presence of variation is directionless in regards that they occur randomly and spontaneously. The variations which are helpful in the adaption of an organism towards its surrondings would be passed on to next generations.
Natural selection is the most critical evolutionary process,which can be considered directional as it leads to only one path that is selection and prepetuation of better adapted individuals.Natural selection leads to survival of the fittest and disappearance of all those organism which do not fit in the prevailing environmental conditions.

BOD refers to the amount of oxygen that would be consumed if all the organic matter in one litre of water were oxidised by bacteria. The microbes biodegrade the major part of the organic matter in the effluent by using the dissolved oxygen. It reduces the BOD of the effluent.
When the BOD of sewage is reduced significantly, the effluent is passed into a settling tank where the bacterial flocs are allowed to sediment forming the activated sludge. Hence, higher the value of BOD, more is the water polluted and more is the amount of biodegradable matter in it.

In a monohybrid test cross, involving a heterozygous tall plant (Tt) and a pure dwarf plant, the progeny consists of tall and dwarf plants in the ratio of 1:1

Suggested methods for this couple include IVF, ZIFT, and AI.

The genotypes of parents must be Hb^A Hb^S and Hb^A Hb^S .

1.Several microbes are used in preparing medicines.
2.The most important medicines for which microbes are used are antibiotics.  These are chemical compounds produced by some microbes and are used to kill or to subside the growth of other disease-causing microbes. Streptomycin, tetracycline and penicillin are some of the commonly used antibiotics. These antibiotics have significantly contributed towards the welfare of the human society.

(i) Oral pills
(ii) Surgical method
(iii) Surgical method
(iv) Barrier method
(v) Barrier method
(vi) Barrier method

Contraceptive pills should be taken daily for a period of 21 days starting within first five days of menstrual cycle (to be repeated after a gap of 7 days).

(a) Neutrophils and macrophages dispose off microbes and dead cell by feeding on them. Hence, they are called the soldiers and scavengers of the animal body.
(b) Consumption of alcohol brings blurred vision, slows down the response of body, impairs judgement and reduces coordination of limb muscles. Hence, one should avoid driving after intake of alcohol.
(c) Persistent use of corticosteroids is harmful because it may cause osteoporosis.

(a) Ovary is superior
(b) Flower is hypogynous because all the floral arise from thalamus below the level of ovary
(c) Ovule is anatropous because it is completely inverted. The micropyle is near the hilum and faces down towards the placenta.The embryo sac is straight.
(d) The ovary of the flower gets converted into fruit after fertilization.
(e) A = Stigma, B = Style, C = Ovary and D = Ovule 

(a) Genetic RNA-Double stranded RNA of mammalian reovirus
Non-genetic RNA-Ribosomal RNA, messenger RNA or transfer RNA
(b)Prolaryotic mRNA is short lived and hardly undergoes processing(capping, methylation and polyadenylation)to from comparatively stable mRNA.

Certain bacteria and cyanobacteria are nitrogen fixers.They convert atmospheric free nitrogen into ammonium form which is easily assimilated by higher plants.Thus, these microorganisms increase the fertility of soil without causing any environmental harzards and therefore, called biofertilizers.Example - Rhizobium and Anabaena.   

(i) 250 million ; pangaea 
(ii) seas ; barriers
(iii) six ; Ethiopian
(iv) birds ; all animals and plants
(v) Charles Darwin ; organic evolution.

a=Wheat b=Pusa Gaurav
c=Bacterial blight d= Chilli mosaic virus and leaf curl.

(i) (a) Sertoli cells
(b) Seminiferous tubule
(c) Spermatozoa
(d) Spermatogonia
(e) Interstitial cells.
(ii) Function of parts:
(a) Sertoli cells provide nutrition to developing spermatozoa.
(b) Spermatozoa are formed in the seminiferous tubules from spermatogonia that arise from germinal epithelial cells.
(c) These are male gametes which fertilize the ovum.
(d) The spermatogenic cells of germinal epithelium lining the seminiferous tubules by mitotic divisions produce spermatogonia. The latter undergo meiotic division to form spermatozoa.
(e) Interstitial cells secrete male sex hormones (Testosterone).

1) By using the heavy isotope of nitrogen.they could find out the semiconservative nature of DNA replication as the densities of DNA having in\( { 15 }_{ N }\) both the strands \( { 15 }_{ N }/{ 14 }_{ N }\) DNA and \( { 14 }_{ N }/{ 14 }_{ N }\) DNA were all different.
2) The hybrid DNA (\( { 15 }_{ N }/{ 14 }_{ N }\) DNA ) had a density intermediate between that of heavy DNA  (\({ 15 }_{ N }/{ 15 }_{ N }\) DNA) and that of light/normal DNA (\({ 14 }_{ N }/{ 14 }_{ N }\) DNA)

1.Population is large enough and there is free flow of genetic material among individuals.
2. Mating takes place at random.
3. Mutation does not take place or occurs at same rate in both directions.
4. There is either nil or negligible immigration or emigration.

The meaning of the given words are as given below
Race. It is a classification system used to categorise humans into large and distinct populations or groups
by anatomical, cultural, linguistic, geographical, historical and for religious relationship.
Breed. It is a specificgroup ofdomestic animals or plants having homogenous appearance and behaviour
and other characteristics that distinguish it from other animals or plants of the same species. They were formed through selective breeding.
Cultivar. It is a plant or grouping of plants selected for desirable characteristics that can be maintained by propagation. 'Cultivar' stands for 'cultivated variety'.
Variety. A variety arises naturally in the plant kingdom and plant grown from its seeds will typically come true to type.