NEET BIOLOGY

Detailed explanation-1: -During meiosis, homologous chromosomes (1 from each parent) pair along their lengths. The chromosomes cross over at points called chiasma. At each chiasma, the chromosomes break and rejoin, trading some of their genes. This recombination results in genetic variation.

Detailed explanation-2: -The answer has to do with the fact that each parent actually has two different sets of genes. And that each parent passes only half of their genes to their child. And that the half that gets passed down is random. All of this together ensures that each child ends up with a different, unique set of genes.

Detailed explanation-3: -After all, kids get their genes from the same parents. But brothers and sisters don’t look exactly alike because everyone (including parents) actually has two copies of most of their genes. And these copies can be different. Parents pass one of their two copies of each of their genes to their kids.

Detailed explanation-4: -Crossing over is a cellular process that happens during meiosis when chromosomes of the same type are lined up. When two chromosomes-one from the mother and one from the father-line up, parts of the chromosome can be switched. The two chromosomes contain the same genes, but may have different forms of the genes.

Detailed explanation-5: -The resulting cells from meiosis are not genetically identical because of the recombination of genes that occurred during prophase 1. Sex cells in humans are produced by meiosis. In males, all four child cells are sperms while in females, one child cell is an egg and the other 3 are polar bodies.