(i) Genetic engineering is the manipulation and transfer of genes from one organism to another organism to create a new DNA called as recombinant. DNA (rDNA).

The two important properties of stem cells that differentiate them from other cells are:
(i) Its ability to divide and give rise to more stem cells by self-renewal
(ii) Its ability to give rise to specialised cells with specific functions by the process of differentiation.

i) They are eco-friendly.
ii) They do not cause pollution like artificial fertilizers.
iii) Help to safeguard natural resourses.

Embryonic stem cells, Adult stem cell or somatic stem cell.

Genetic engineering is the manipulation and transfer of genes from one organism to another organism to create a new DNA called as recombinant DNA (rDNA)

Selection is one of the oldest methods of plant breeding in which individual plants or groups of plants are sorted out from a mixed population based on the morphological characters.
Methods of selection:
There are three methods of selection. They are
a) Mass selection
b) Pure line selection
c) Clonal selection
a) Mass selection:
(i) Seeds of best plants showing desired characters are collected from a mixed population.
(ii) The collected seeds are allowed to raise the second generation. This process is carried out for seven or eight generations.
(iii) At the end, they will be multiplied and distributed to the farmers for cultivation. Eg: Groundnut varieties like TMV-2 and AK-10.
b) Pureline selection :
(i) Pureline is "the progeny of a single individual obtained by self breeding":
(ii) This is also called as individual plant selection. In pureline selection large numbers of plants are selected from a self pollinated crop and harvested individually.
(iii) Individual plant progenies from them are evaluated separately. The best one is released as a pureline variety.
(iv) Progeny is similar both genotypically and phenotypically.
c) Clonal selection:
(i) A group of plants produced from a single plant through vegetative or asexual reproduction are called clones.
(ii) All the plants of a clone are similar both in genotype and phenotype.
(iii) Selection of desirable clones from the mixed population of vegetatively propagated crop is called clonal selection.

(i) DNA fingerprinting technique is widely used in forensic applications like crime investigation such as identifying the culprit.
(ii) It is also used for paternity testing in case of disputes.
(iii) It also helps in the study of genetic diversity of population, evolution and speciation.

Protina, shakti and Rathna are lysine rich maize hybrids.

(i) Insulin used in the treatment of diabetes.
(ii) Human growth hormone used for treating children with growth deficiencies.
(iii) Blood clotting factors are developed to treat haemophilia.
(iv) Tissue plasminogen activator is used to dissolve blood clots and prevent heart attack.
(v) Development of vaccines against various diseases like Hepatitis B and rabies.

Mutation:
(i) Mutation is defined as the sudden heritable change in the nucleotide sequence of DNA in an organism.
(ii) It is a Process by which genetic variations are created which in turn brings about changes in the organism.
(iii) The organism which undergoes mutation is called a mutant.
(iv) The factors which induce mutations are known as mutagens or mutagenic agents.
(v) Mutagens are two types namely physical mutagens and chemical mutagens.
(i) Physical mutagens:
Radiations like X-rays, α, β and γ-rays, UV rays, temperature, etc. which induce mutations are called physical mutagens.
(ii) Chemical mutagens:
(i) Chemical substances that induce mutations are called chemical mutagens.
(ii) Eg: Mustard gas and nitrous acid. The utilization of induced mutation in crop improvement is called mutation breeding. Achievements of mutation breeding:
Achievements of mutation breeding:
(i) Sharbati Sonora wheat produced from Sonora-64 by using gamma rays.
(ii) Atomica 2 rice with saline tolerance and pest resistance.
(iii) Groundnuts with thick shells.