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Lesson 22 of 84 · Crosscutting Concepts
ExperimentDNA: The Code of Life (Part 2)
What You'll Learn
Genes are segments of DNA that code for specific traits like eye color, hair texture, and blood type. Humans have approximately 20,000 genes spread across 23 pairs of chromosomes.
Key Words
- nucleus
- DNA
Materials Needed
- onion skin
- iodine stain
- paper
Safety First
- Wash hands after handling materials.
Steps
Step 1 — Read
Read the introduction and identify the main idea of this lesson.
Step 2 — Do
Model mitosis using pipe cleaners as chromosomes. Show each phase: prophase, metaphase, anaphase, and telophase.
Step 3 — Observe
Use your senses (except taste) to describe what you notice.
Step 4 — Record
Write a summary of your findings in 3-5 sentences.
Check Your Understanding
Question 1
1 of 3What is a gene?