define 3 laws of heredity given by mendel ?

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Fakeha Anis answered this

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Shristi Raj answered this

When traits are passed from one generation to another they follow principles of genetic inheritance that were first defined by Gregor Mendel, a monk and scientist who worked in the mid-nineteenth century. Mendel's studies yielded three "laws" of inheritance: the law of dominance, the law of segregation, and the law of independent assortment. Each of these can be understood through examining the process of meiosis. Meiosis

When a cell duplicates its DNA and divides twice to produce four gametes, or reproductive cells, the process is called meiosis. Most cells in the body are diploid, meaning they have two copies of each chromosome. But because gametes have gone through meiosis, they have one copy of each chromosome and are haploid. During sexual reproduction two gametes, called the egg and sperm, join together and form a diploid cell that will eventually become an individual organism. This diploid cell, called a zygote, received one copy of each chromosome from each parent. The appearance, or phenotype, of the new individual will depend on whether it inherited recessive or dominant copies of various alleles from its parents. Variant copies of genes are called alleles, and since plants and animals are diploid they have two alleles for each gene.

Shristi Raj answered this

Gregor Mendel developed the model of heredity that now bears his name by experiments on various charactersitics of pea plants: height (tall vs. Short); seed color (yellow vs. Green); seat coat (smooth vs. wrinkled), etc. The following explanation uses the tall/short trait. The other traits Mendel studied can be substituted for tall and short.

Mendel started out with plants that "bred true". That is, when tall plants were self-pollinated (or cross-pollinated with others like them), plants in following generations were all tall; when the short plants were self-pollinated (or cross- pollinated with others like them) the plants in following generations were all short.

Mendel found that if true breeding Tall [T] plants are crossed (bred) with true breeding short [t] plants, all the next generation of plants, called F1, are all tall.

Next, he showed that self-pollinated F1 plants (or cross- pollinated with other F1 plants) produce an F2 generation with 3/4 of the plants tall and 1/4 short.

A. 1/4 of the F2 generation are short plants, which produce only short plants in the F3 generation, if they are self- pollinated (or crossed with other short F2 plants;) these F2 plants breed true.
B, 1/4 of the F2 generation (1/3 of the tall plants) are tall plants that produce only tall plants in the F3 generation, if they are self-pollinated; these tall F2 plants breed true.
C. 1/2 of the F2 generation (2/3 of the tall plants) are tall plants that produce 1/4 short plants and 3/4 tall plants in the next [F3] generation, if they are self-pollinated. This is the same proportion of tall to short that F1 plants produce.