Lesson Plan

• Describe the main components of a chromosome (DNA, histone proteins, sister chromatids, centromere, telomeres).
• Explain how DNA is organized around histone octamers to form nucleosomes.
• Compare the roles of the centromere and telomeres in chromosome stability and segregation.
• Illustrate the relationship between sister chromatids and the centromere during mitosis.
• Label a chromosome diagram accurately using appropriate terminology.

• Projector and digital slide deck
• Printed chromosome diagram handouts
• Paper nucleosome model kits (paper strips, beads)
• Whiteboard and markers
• Worksheet for labeling activity
• Exit‑ticket cards

Begin with a quick “What do you already know about DNA?” poll to activate prior knowledge. Explain that today’s focus is on how DNA is packaged into chromosomes, highlighting the five key structures. State that students will be able to label and describe each part by the end of the lesson.

1. Do‑now (5 min): Sticky‑note quiz on basic DNA facts; teacher reviews answers.
2. Mini‑lecture with slides (10 min): Introduce DNA, histone proteins, nucleosome formation.
3. Hands‑on model building (10 min): Students construct a paper nucleosome and discuss how DNA wraps around histones.
4. Guided diagram labeling (10 min): Using handouts, students label DNA, histones, sister chromatids, centromere, and telomeres; teacher circulates for formative feedback.
5. Think‑pair‑share (5 min): Explain the distinct functions of the centromere versus telomeres.
6. Summary & exit ticket (5 min): Students write one thing they learned and one lingering question on a card.

Recap the five chromosome components and their roles, checking understanding through a rapid verbal review. Collect exit tickets to gauge mastery and identify misconceptions. For homework, assign the textbook section on chromosome structure and an online quiz to reinforce labeling skills.