How Traits Are Made

This video introduces traits and describes how they are shaped by both genes and the environment (context).

1. Project video to the whole class
2. Go through the discussion items below either before or after showing the video

• An organism's traits are the product of both genetic and environmental factors.
• Genes are instructions for making proteins.
• The combination of proteins an individual makes affects their combination of traits.

News headlines include phrases like “gene for human speech” or “friendliness gene.” This is “gene for” thinking, and it’s closely related to the “Each trait is influenced by one gene” misconception. In reality, it takes many genes, plus environmental factors, to make almost any trait.

The use of the word “context” in place of “environment” in this video is purposeful. Often, the phrase “environmental factors” brings to mind just external exposures. But in genetics, environmental factors are anything outside of DNA that can affect traits, including internal factors. The text beneath the video explains this thinking in greater detail in a student-friendly way.

Consider using the Frayer Model to discuss synonyms.

How Traits Are Made

• What are some traits you can think of? What are some traits that aren’t physical appearances? What do you think causes traits to be different? What isn’t a trait?
• How do you think genes make/build traits? What are you made out of?
• What does the word “context” mean in the video? What are some other words that the video uses to mean “environmental factors”?
• What are some ways the environment could affect traits? What is the environment? Discuss internal and external environments.