NEET BIOLOGY

Detailed explanation-1: -When cells become damaged or die the body makes new cells to replace them. This process is called cell division. One cell doubles by dividing into two. Two cells become four and so on.

Detailed explanation-2: -Mitosis is a fundamental process for life. During mitosis, a cell duplicates all of its contents, including its chromosomes, and splits to form two identical daughter cells. Because this process is so critical, the steps of mitosis are carefully controlled by certain genes.

Detailed explanation-3: -When one cell divides into two, both must have a copy of the genetic information. Therefore, before cell division occurs, the genes must also make duplicates of themselves so that all of the important genetic information ends up in each of the new cells.

Detailed explanation-4: -Mitosis is the reason we can grow, heal wounds, and replace damaged cells. Mitosis is also important in organisms which reproduce asexually: this is the only way that these cells can reproduce. This is the one key process that sustains populations of asexual organisms.

Detailed explanation-5: -In meiosis the germ cell divides into four sex cells, each cell consisting of half of the parent cell’s chromosomes. Mitosis is necessary for cell growth, repair, and regeneration. Dead cells are replaced by mitosis since the number of chromosomes is not changed in a cell after division in mitosis.