Dominance & segregation laws | Heredity & Evolution | Biology | Khan Academy

Khan Academy India - English14 minutes read

Mendel's experiment with pea plants helped explain how dominant and recessive traits are passed down, clarifying how traits like blue eyes can appear in a generation with brown-eyed parents. Understanding Mendel's laws, including the Law of Segregation, can provide insights into predicting offspring ratios and inheritance patterns.

Insights

  • Mendel's experiment with pea plants demonstrated the Law of Dominance, where dominant traits overshadow recessive ones, leading to specific ratios in offspring.
  • Understanding Mendel's laws of inheritance can clarify how seemingly contradictory traits, like blue eyes from brown-eyed parents, can be passed down through generations.

Get key ideas from YouTube videos. It’s free

Recent questions

  • How do dominant and recessive traits affect inheritance?

    Dominant traits mask recessive traits in offspring.

  • What is the significance of the Law of Segregation in genetics?

    The Law of Segregation explains how traits are passed on.

  • How does self-pollination affect genetic traits in plants?

    Self-pollination can result in a mix of genetic traits.

  • Can recessive traits skip a generation in inheritance?

    Yes, recessive traits can skip generations.

  • How can Mendel's laws help explain inheritance patterns?

    Mendel's laws provide a framework for understanding genetic inheritance.

Related videos

Summary

00:00

Inheritance Laws: Dominance, Segregation, and Offspring Ratios

  • Marcus has blue eyes, but his parents have brown eyes, leading to the question of how this is possible.
  • Mendel's experiment involved crossing a pure tall pea plant with a pure short pea plant, resulting in all tall offspring, known as the F1 generation.
  • Mendel then self-fertilized the F1 generation tall plants and obtained a mix of tall and short plants in a 3:1 ratio.
  • The Law of Dominance suggests that both tall and short traits are passed along, with the tall trait being dominant and the short trait recessive.
  • The Law of Segregation explains that during gamete formation, the traits get separated, leading to the 3:1 ratio when self-pollinating.
  • When self-pollinating, the fertilized eggs can result in tall or short plants based on the combination of sperm and egg traits.
  • Applying the same logic to the pure tall and short plants reveals why all F1 generation plants were tall and how the 3:1 ratio occurs.
  • The concept of dominant and recessive traits can explain how a recessive trait can skip a generation and reappear in the next.
  • Applying Mendel's laws can help understand how traits are inherited, such as blue eyes from brown-eyed parents.
  • Recalling the concepts of dominant and recessive traits, the Law of Segregation, and predicting offspring ratios can solidify understanding.
Channel avatarChannel avatarChannel avatarChannel avatarChannel avatar

Try it yourself — It’s free.