02 Chromosomes & DNA

👩‍🏫 Teacher’s Guide

Objective
Students will describe the structure and function of DNA and chromosomes and relate genes to traits.

Vocabulary
DNA, chromosome, nucleus, sequence, express, double helix

Teaching Notes

• Start with a picture, object, or quick demo to activate prior knowledge.
• Define key terms in context and model how to use them in sentences.
• Use quick checks (thumbs up/down, exit slips) to confirm understanding before practice.
• Encourage evidence‑based claims using observations, diagrams, or simple data tables.

🧒 Student Worksheet

Concept and Helping Material

Definition. Genes are segments of DNA; a DNA strand coils to form a chromosome inside the nucleus. The sequence of DNA bases stores instructions that determine trait expression.
Helping ideas and samples:

• Try a quick sort, draw‑and‑label, or compare‑and‑contrast.
• Name one place you see this idea in class or at home.
• Safety note if needed.

Vocabulary and Definition

• — the genetic material that carries instructions for life
• — a package of DNA and proteins in the cell nucleus
• — the cell part that contains chromosomes
• — the order of components, such as bases in DNA
• — to show a trait based on genetic instructions
• — the twisted‑ladder shape of DNA

Words to Learn

e.g. , , , , ,

Sentences to Fill In

1. This topic connects to .
2. A gene is a of DNA that codes for a trait.
3. An organism’s visible traits are its .
4. The order of DNA bases is called the .
5. Two recessive alleles are needed to a recessive trait.

Hands-On Experiment or Activities

What You Need: simple classroom items (paper, markers, sticky notes, beans/counters).
What You Do: 1) observe, 2) record, 3) share.
Think and Talk: What changed? What stayed the same?

Reflection

• What did you learn about this topic?
• Which vocabulary word was hardest, and how will you remember it?