Why are identical twins genetically similar?
Identical twins are genetically similar because they originate from the same fertilized egg (zygote), which splits into two individuals.
Key Idea
| Term | Meaning |
|---|---|
| Zygote | Fertilized egg formed after fusion of gametes |
| Identical Twins | Twins from one zygote splitting |
| Genetic Material | Same DNA sequence |
Process
| Step | Description |
|---|---|
| Fertilization | One egg and one sperm form a zygote |
| Early Development | Zygote starts dividing |
| Split | Zygote splits into two embryos |
| Growth | Both develop into separate individuals |
Stepwise Understanding
Single sperm fertilizes a single egg
One zygote is formed
At early stage, it splits into two parts
Each part develops into a separate individual
Both carry same genetic information
Important Concept
Since both individuals come from the same zygote, their DNA is almost identical.
Real Insight
Even though DNA is same, small differences can still appear due to environmental factors, like habits or lifestyle, so they are not 100 percent identical in behavior.
So identical twins are genetically similar because they share the same origin and same DNA.