NEET BIOLOGY

Detailed explanation-1: -Identical (i.e., monozygotic, or MZ) twins share 100 percent of their genes, whereas fraternal (i.e., dizygotic, or DZ) twins generally share only 50 percent of their genes.

Detailed explanation-2: -Identical or Fraternal? The odds of having identical twins is about 3 in 1, 000 and about a third of all twins are monozygotic. The majority of twins are dizygotic, produced when two separate eggs are fertilized by two different sperm.

Detailed explanation-3: -Polar Body Twins or “Half Identical” These twins are very much alike but aren’t a 100% DNA match-sharing about 75% of their genetic DNA. (Less than identical twins but more than fraternal twins.) To date, polar body twinning remains a theory.

Detailed explanation-4: -It is true that identical twins share their DNA code with each other. This is because identical twins were formed from the exact same sperm and egg from their father and mother. (In contrast, fraternal twins are formed from two different sperm and two different eggs.)