Additive genetic effects

High school (ages 12+)
Human Body

Name:

Date:

Step 1 · Read the article

Open the article and read it at the level above. Then answer the questions below in your own words.

https://smallwhale.org/articles/additive-genetic-effects

Write what each word means, using the article.

Do not copy the article. Write two things you learned, the way you would explain them to a friend.

Answers below are taken from the article’s stored facts, so they match what the student read.

1. What is the heritability (narrow sense)?The proportion of phenotypic variance explained by additive genetic variance (h²)
2. What is the response to selection?The only component of genetic variance that predictably responds to selection
3. How do additive genetic effects help farmers or scientists?They let us predict how a trait will change when we choose the best animals or plants. Because the effects add up, we can use the breeder’s equation to see how much improvement we can get.
4. Why is additive genetic variance important for evolution?It is the raw material that natural selection can use to change a population. If there isn’t enough additive variance, the population can’t adapt well to new environments.

Quantitative Trait Loci (QTL): Regions of DNA that are associated with variation in a quantitative trait.
Epistasis: A phenomenon where the effect of one gene is modified by one or more other genes.
Breeding Value: An estimate of the genetic merit of an individual for a particular trait, based on additive gene effects.