In genetic research, what does the term 'monozygotic twins' refer to?

In genetic research, what does the term 'monozygotic twins' refer to?

• A. Twins from different families
• B. Twins that share identical genotypes
• C. Twins that are raised in the same environment
• D. Twins with different observable traits

Answer: (B)

The term 'monozygotic twins' specifically refers to twins that share identical genotypes because they develop from a single fertilized egg, or zygote, that splits into two embryos. As a result, monozygotic twins have the same genetic material and are therefore genetically identical. This uniqueness is significant in genetic research, as it allows scientists to study the effects of environmental factors on twin development and conditions, knowing that any differences can be attributed to these outside influences rather than genetic variance. The focus on identical genotypes highlights the biological basis of these twins, distinguishing them from other types of twins, such as dizygotic twins, which are formed from two separate eggs fertilized by two different sperm cells and share approximately 50% of their genetic makeup. This distinction is fundamental in understanding inheritance patterns and the role of genetics in health and behavior.

The term 'monozygotic twins' specifically refers to twins that share identical genotypes because they develop from a single fertilized egg, or zygote, that splits into two embryos. As a result, monozygotic twins have the same genetic material and are therefore genetically identical. This uniqueness is significant in genetic research, as it allows scientists to study the effects of environmental factors on twin development and conditions, knowing that any differences can be attributed to these outside influences rather than genetic variance.

The focus on identical genotypes highlights the biological basis of these twins, distinguishing them from other types of twins, such as dizygotic twins, which are formed from two separate eggs fertilized by two different sperm cells and share approximately 50% of their genetic makeup. This distinction is fundamental in understanding inheritance patterns and the role of genetics in health and behavior.