Vegetative reproduction is also a type of asexual reproduction; it is because it involves a single parent and there is no formation or fusion of gametes. The term clone is applicable to the individuals formed by vegetative reproduction, because they are genetically and morphologically identical among themselves and to the parent.

Since single-celled organisms reproduce by cell division (into two new individuals), there is no natural death for them.

The fruits selected to induce parthenocarpy can be watermelon, papaya, etc. It is because these fleshy fruits have a large number of seeds, which interfere with the preparation of jams, jellies, etc.

a) Inner cell mass. It forms the tissues of future embryo
b) Morula
c) In the inner cell mass.
d) The pole of the blastocyst that contains the inner cell mass

Ex-situ. Any two differences between ex-situ and in-situ conservation of biodiversity.

If I had been cow , I would have rumen , I would be able to  eat  straw  which  is  a  cellulosic material and digest it with the help of Methanogens ( Methane generating  bacteria)

(i) Hot spots of biodiversity. The concept of 'Hot-spots' was developed by Norman Myres (1988) to designate specific areas for in-situ conservation. The conservation the hot spots are the richest and most threatened reservoirs of plants and animal life on earth.
The criteria for determining hot spots are:
1. Number of endemic species.
2. Degree of threat which is measured in terms of habitat loss.
There are 25 hot spots in the world out of which two are in India. They are Western Ghats and eastern Himalayas.
Hot spot of Eastern Himalayas are active centres of evolution and rich in diversity of flowering angiosperms. Western Ghats have semi evergreen forests. Western Ghats include two main centres of biodiversity i.e. Agastyamalai hills and Silent valley.
(ii) Ex-situ conservation. It means maintenance of off site collections either in gardens by farmers, botanical garden for storing seeds, genes, pollen, tissue culture etc.
The rare plants have been found to flourish in large numbers under the care and protection of gardeners and nature lovers.
The farmers have been maintaining genetic diversity (enormous varieties) of crop plants since ancient times by saving seeds or other components for the next plantings.
Collection of samples of cultivated and wild varieties of plants and storing them in botanical gardens is another method of conservation of germplasm.
In seeds, the living meterial remains in metabolically suspened state. When the seeds are to be stores for longer periods, it is necessary to avoid conditions which favour respiration and enzymatic actions.
(iii) India's effort in biodiversity conservation. India has greatly contributed to conservation of biodiversity owing to its great utility and need for conservation. The following measures have been taken for this purpose:
1. Setting up bodies like Indian Board for Wildlife, Bombay Natural History  etc.
2. observation of first week of October as national wildlife week.
3. Introduction of Wildlife Protection Act in 1972.
4. Setting up of sanctuaries, national parks and biosphere reserves.

1. Alexander Fleming, while working on Staphylococci bacteria, observed a mould growing in one of the unwashed culture plates, around the mould the bacterium could not grow.
2. He found that it was due to a chemical produced by the mould Penicillium notatum and named the chemical as Penicillin.
3. Its full potential as an antibiotic was established later by Ernst Chain and Howard Florey.

1. The prokaryotes / bacteria have restriction enzyme to restrict the growth of bacteriophage.
2. They do so by cutting the DNA of the phage with restriction enzyme.

(a) The recombinant/transformant can be selected out from the non-recombinants/non-transformants by plating the transformants on ampicillin containing medium.
1. The transformants will grow in it, while the non-transformants will not grow.
(b) It acts as a selectable marker.

(i) The mucus coating of the gut epithelium is a barrier that traps microbes.
(ii) The hydrochloric acid secreted by gastric glands retards the growth of microbes.
This type of immunity is called innate immunity, which occurs right from birth.

(a) Contact inhibition is the property shown by normal cells,by the virtue of which contact with other cells inhibits their uncontrolled proliferation and growth.
(b) All normal cells have cellular oncogenes (c-onc) or proto-oncogenes;when activated under certain conditions,such genes could lead to oncogenic transformation of cells,i.e.they become cancerous.

1. Lactose is the inducer for lac operon. The active form of lactose binds to the repressor protein and brings about a conformational change in the repressor.
2. As a result, the repressor is inactive, i.e. it cannot bind to the operator.
3. This provides access of the RNA polymerase to structural genes and transcription and production of enzymes continue and metabolism of lactose takes place.
4. In its absence, the repressor is active and binds to the operator, thereby switching off the process.

(i) AUG GAG UAC UUC GUG UGA
(ii) It will code for five amino acids
The last codon UGA is a termination codon that does not code for any amino acid.

1. In prokaryotes, the mRNA does not require any processing to become active.
2. Transcription and translation occur in the same compartment-cytosol, as there is no well-defined nucleus. So coupling of transcription and translation is possible.
3. The mRNA has to be processed before becoming active (splicing is necessary).
4. Since nucleus and cytoplasm are well separated, in eukaryotes the RNA has to be transported to the cytoplasm for translation.
5. So coupling of transcription and translation is not possible.

1.The presence of 2'OH-group of ribose makes RNA more labile and prone to degradation.
2.In the heat-killed S-strain,it would not have remained functional and hence would not have transformed the R-cells into S-cells.

1.The gene for haemophilia is present in the X-chromosome.
2.The son receives the X-chromosome from his mother; so a carrier-mother passeson the disease to 50% of her sons.
3. When the mother is normal, the sons .have no chance of getting the disease, even if the father is haemophilic, because father passes on the Y-chromosome to his sons.

The other possible types of dominance are:
(i) Incomplete dominace.
e.g. Flower colour in snapdragon.
(ii) Codominance.
e.g. Blood group AB.

The two male gametes produced by a pollen grain are used in the fertilisation of one ovule.
One male gamete fuses with the female gamete to form the zygote, i.e. syngamy.
The second male gametes fuses with the secondary nucleus, to form the triploid primary endosperm nucleus (PEN), i.e. triple fusion.
As double fertilisation (two fusions) occurs in the ovules of angiosperms, ten pollen grains are necessary to fertilise ten ovules.

1.Hymen is the membrane that partially covers the vaginal opening.
2.The hymen gets torn during the first coitus.
3. But it can also be torn by active participation in sports like horse-riding,cycling,or by a sudden fall or jolt and insertion of vaginal tampon;so its presence or absence cannot indicate virginity.

1. In haploid organisms, meiosis occurs during development of zygote.
2. It is the only diploid stage (formed by the fusion of two haploid gametes) in the life-cycle that can undergo meiosis.

1. In haploid organisms, showing haplontic life cycle, gamete formation involves only mitosis; the diploid zygote formed by the fusion of two haploid gametes, undergoes meiosis (zygotic meiosis).
2. In diploid organisms, showing diplontic or haplodiplontic life cycle, gamete formation involues meiosis (gametic meiosis) and haploid gametes are formedl; the diploid zygote undergoes mitosis to form diploid individuals.

1. It is a case of polyembryony, the phenomenon of occurrence of more than one embryo in a seed.
2. It is possible in the following ways:
(i) Some of the nucellar cells surrounding the embryo sac start dividing, protrude into the embryos.
(ii) Synergids of the embryo sac divide and form embryos.

1. Since geitonogamy involves two different flowers of the same plant, it is genetically similar to autogamy; both autogamy and geitonogamy do not result in genetic variation in the progeny.
2. Geitonogamy and cross-pollination involve different flowers and a pollinating agent.

1. Since geitonogamy involves two different flowers of the same plant, it is genetically similar to autogamy; both autogamy and geitonogamy do not result in genetic variation in the progeny.
2. Geitonogamy and cross-pollination involve different flowers and a pollinating agent.