EMBRYOLOGY
FEMALE SEX GLAND OVARIES ÖOGENESIS AND MENSTRUAL CYCLE
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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1 egg 2 sperm egg splits
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2 eggs 1 sperm
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1 egg 1 sperm egg splits
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2 egg 2 sperm
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Detailed explanation-1: -To form identical or monozygotic twins, one fertilised egg (ovum) splits and develops into two babies with exactly the same genetic information. To form fraternal or dizygotic twins, two eggs (ova) are fertilised by two sperm and produce two genetically unique children.
Detailed explanation-2: -Monozygotic (MZ) twins, also called identical twins, occur when a single egg cell is fertilized by a single sperm cell. The resulting zygote splits into two very early in development, leading to the formation of two separate embryos. MZ twins occur in 3 to 4 per 1, 000 births worldwide.
Detailed explanation-3: -If more than one sperm fuses-a condition called polyspermy-multipolar or extra mitotic spindles are formed, resulting in faulty segregation of chromosomes during cell division; nondiploid cells are produced, and development usually stops. Two mechanisms can operate to ensure that only one sperm fertilizes the egg.