During RNA processing
(i)unwanted nucleotides are removed
(ii)useful regions are rejoined
(iii)certain nucleotides are added
(iv)some nucleotides are modified, and
(v)folding of molecule

1.The primary follicle grows and becomes fully mature Graafian follicle.
2. Secretion of estrogen hormone.
3. Endometrium of uterus regenerates through proliferation.

The lymph nodes serve to trap the microorganisms and other antigens which have entered the lymph and tissue fluid.

These trapped antigens activate the lymphocytes present in the lymph nodes to cause immune response. 

(i)Test-tube baby program
In this method ova from the wife or a donor female and the sperms from the husband or a donor male are allowed to fuse under simulated conditions in the laboratory.
The zygote or early embryo is implanted into the fallopian tube or uterus for further development.
(ii)Intracytoplasmic sperm injection(ICSI)
In this method the sperm is directly injected into the ovum to form the zygote and then embryo transfer is cerried out.

Partiruition refers to the process of delivery if the fully-developed foetus,i.e.,childbirth.
Relaxin and oxytocin are the hormones involved in the process.

Primary endosperm cell forms the kernel of coconut.
Difference
The kernel of coconut is the cellular endosperm, while the coconut water is the free-nuclear endosperm.

(a) (i) Penicillium    
(ii) Chlamydomonas
(b) 

(a) Orchids, carnation Gladiolus chrysanthemum and other ornamental plants.
(b) Tissue culture technique.
(c) Advantages of vegetative propagation 
1.Ther is rapid multiplication of plants.
2. This technique has been applied for production of disease free plants.

(b) (i) The egg cell on fertilisation becomes the zygote, which later forms the embryo
(ii) The polar nuclei fuse to form a diploid secondary nucleus; on fertilisation by a male gamete, it forms the primary endosperm nucleus, which later forms the endosperm.

(i) 60000-80000 primary follicles
(ii) 

(a) Process-Fertilization
Product-Zygote
(b) (i) Oviparous animals
(ii) These eggs are either shelled or covered by protective coverings.
(iii) In frog (amphibians) Unfertilized eggs are released. In reptiles and birds, fertilized eggs are released.
(c) (i) Viviparous animals.
(ii) Developing embryo draws nutrition from mother through placenta.

(i) Oral pills contain hormones such as progestron and estrogen.Oral administration of small doses of either progestron or progesterone-estrogen combinations is another contraceptive method used by the females.They are used in the form of tablets and hence are popularly called the 'pills'.
Functions. 
1. They inhibit ovulation and implantation as well as alter the quality of cervical mucus to prevent/retard entry of sperms.
2. Pills are very effective with lesser side effects and are well accepted by the females.
Advantages of Saheli. 'Saheli', the new oral contraceptive for the female contains a non-steroidal preparation called  'centchroman'. It is a 'once a week' pill with very few side effects and high contraceptive value.
(ii) Schedule. Pills have to be taken daily for a period of 21 days starting preferably within the first five days of menstrual cycle. After a gap of 7 days (during which menstruation occurs) it has to be repeated in the same pattern till the desired period on contraception.

(i) a- Spermatogonia
 b-Interstitial cells or Leydig cells
 c-Spermatozoa.
(ii)a-Spermatogonia produce the spermatozoa (sperms).
 d-Sertoli cells provide nutrition to the germ cells.

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.

1. Transcription unit in a bacterium consists of a promoter, structural genes, terminator and the enzyme DNA dependent RNA-Polymerase.
2. In bacteria, there is a single RNA polymerase, which catalyses transcription of all the three types of RNAs (mRNA, tRNA and RNA)
3. It also facilitates opening of the double helical DNA and only the DNA strand with \({ 3 }^{ ' }\longrightarrow { 5 }^{ ' }\) polarity is transcribed, as the enzyme can polymerise the nucleotides only in \({ 5 }^{ ' }\longrightarrow { 3 }^{ ' }\) direction.
4. Once the polymerase reaches the terminator sequence, the nascent RNA falls off and termination of transcription occurs.

The doctor must have used Pedigree analysis; which refers to the analysis of distribution and movement of traits in a series of generations of a family. Since the non-haemophilic parents give rise to a haemophilic child, the genotypes of them should be

(a) (i) On the exine of pollen grains while in the microsporangia.
(ii) In the central cell of embryo sac of the ovule.
(iii) From the pollen sacs.
(iv) In the ovule.