Page 166 - Science Course 3 (Book 1)

Mo4-L5b: What Influences Traits?

An organism’s social group also can affect color,
body structure, or behavior.

Change in pH
level of soil

Key Concept

What Influences Traits?

What are some environmental factors that can
influence phenotype?

A mutation is a permanent change in the sequence
of DNA in a gene.

Some mutations in egg or sperm cells occur if an
organism is exposed to harsh chemicals or severe
radiation, but most mutations occur randomly.

Correct Copy

Mutant Copy

Key Concept

What Influenes Traits?

When an organism’s phenotype changes in response How can mutation influence a trait?
to its environment, the organism’s genes are not
affected and the change cannot be passed on to the
next generation.

The only way that a trait can change so that it can be
passed to the next generation is by mutation, or
changing an organism’s genes.

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