Mutations and Variation (Part 3)

What You'll Learn

Genetic variation within a population is essential for evolution. Variation comes from mutations, sexual reproduction, and gene flow between populations.

Key Words

trait
dominant
recessive

Materials Needed

onion skin
iodine stain
paper
colored pencils
coins (for Punnett squares)
tape

Safety First

Tie back long hair before starting the experiment.

Steps

Step 1 — Read

Review the background information on Evolution before starting.

Step 2 — Do

Prepare a wet-mount slide of an onion skin and observe it under a microscope (or magnifying glass). Draw and label the cell wall, cell membrane, and nucleus.

Step 3 — Observe

Watch carefully for any changes and note the time.

Step 4 — Record

Create a data table to organize your measurements.

Check Your Understanding

Question 1

1 of 3

What does DNA stand for?