Fraternal twins in man are produced when
Two sperms fertilize an ovum and the first two blastomeres separate from each other
One sperm fertilizes an ovum and first two blastomeres separate from each other
Egg develops parthenogenetically and first two blastomeres separate from each other
Two ova are fertilized simultaneously
The zygote passes through several developmental stages till implantation, Describe each stage briefly with suitable diagrams.
The fertilized egg divides by the process of
Blastocyst is a modified blastula of
If $X$ chromosome contained sperm entered in $X$ chromosome contained ovum than ...... is produced
Normally the number of chromosomes in the nuclei of gametes that fuse at fertilization are