If a cell has 40 chromosomes at the beginning of mitosis, how many chromosomes will be present in the daughter cells?

40

Explanation:

Mitosis is an equational division and forms two genetically identical daughter cells from one parent cell that enters the process. DNA replication during the S phase of the cell cycle is followed by chromosome replication and the presence of two sister chromatids in each chromosome. Anaphase of mitosis includes splitting of centromere and separation of sister chromatids of each chromosome.

These sister chromatids are now called daughter chromosomes and move towards the opposite poles of the cell. Therefore, a cell with 40 chromosomes would have 40 daughter chromosomes present at each pole of the cell by the end of anaphase. The formation of nuclear envelop and cell membranes around them results in the formation of two daughter cells each carrying 40 chromosomes.

Keratin has two main functions: to adhere cells to each other and to form a protective layer on the outside of the skin. In epithelial cells, keratin proteins inside the cell attach to proteins called desmosomes on the surface. The desmosomes act as anchors, holding the cells together.