Multiple choice

We are all unique. Every one of us has a unique combination of traits. Which among the following variable traits are influenced by a combination of genes and environmental factors?

  1. Earlobe attachment

  2. Tongue rolling

  3. Dimples

  4. Handedness

  5. Freckles

Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Some people can curl up the sides of their tongue to form a tube shape. Tongue rolling is controlled by a single gene. However, people can learn to roll their tongue as they get older, suggesting that environmental factors also influences the trait.