During cleavage of the mammalian zygote, the resultant blastomeres become smaller and smaller. Comment on this statement.

Explanation

The repeated division of fertilised egg into a group of smaller cells is called cleavage. The first cleavage is vertical and produces two unequal cells. The second cleavage is at right angles and produces 4 cells. The subsequent divisions are rapid and as a result a solid mass of cells which resemble the mulberry fruit and is known as morula. The resultant blas telomeres are small because it may be due to division of labour, i.e., each cell has a message to form certain organs. During organogenesis these cells form the organs by differentiation.