Question

Cleavage in the fertilised egg of humans__________.

• A. starts in uterus
• B. starts when fertilised egg is in fallopian tube
• C. results in the formation of embryo with 8-16 blastomeres called as blastocyst
• D. starts in cervix

Answer 1

The correct option is B starts when fertilised egg is in fallopian tube

The ovum is fertilised by the sperm in the fallopian tube of the female leading to the formation of a diploid zygote.

Zygote (fertilised egg) undergoes mitotic divisions to develop into an embryo.

The mitotic divisions start as the zygote moves through the isthmus of the oviduct (fallopian tube) towards the uterus.

The mitotic divisions of the zygote is called cleavage and it results in the formation of blastomeres.

The embryo with 8 to 16 blastomeres is called morula.

Morula divides further resulting in the transformation of morula into blastocyst.