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Q. 74.9( 14 Votes )

Give the basic features of the mechanism of inheritance.

Class 10th NCERT - Science Exemplar 9. Heredity and Evolution

Answer :

Transmission of genetic characteristic from one generation to next is termed as inheritance. The basic features of the mechanism of inheritance are-

•Each genetic character is controlled by a gene.

•Genes are units of hereditary and are responsible for inheritance. Genes controls the expression of a trait or a character in an organism. Genes are located on the chromosomes inside the nucleus of the cell.

•Each gene has two or more alternating forms called as alleles. One of the allele is dominant while other is recessive.

•Each parent possesses a pair of genes for each characteristic on a chromosome.

•Each cell has two copies of each chromosome, one each from the male and female parents.

•Every germ-cell will take one chromosome from each pair and these may be of either

• maternal or paternal origin.

• When two germ cells combine, they will restore the normal number of chromosomes in the progeny, ensuring the stability of the DNA of the species

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PREVIOUSEvolution has exhibited a greater stability of molecular structure when compared with morphological structures. Comment on the statement and justify your opinion.NEXTIn the following crosses write the characteristics of the progenya). RRYY x RRYY (round yellow x round yellow)b). RrYy x RrYy (round yellow x round yellow)c). rryy x rryy (wrinkled green x wrinkled green)d). RRYY x rryy (round yellow x wrinkled green)

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