Overarching Question: What makes something alive?

Guiding Question: How do cells heal your body?

Multiplying by Dividing:

■ Procedure:❑ Get a half sheet of paper and a scissors.❑ Use the scissors to cut your paper in half, then

count the number of paper squares you have.❑ Stack the paper squares up and cut them in half

again. Then count the number of squares.❑ Repeat this procedure 3 more times. Count the

squares each time.

Cell Division Activity Chart

Number of times cut in half

Number of paper squares

1

2

3

4

5

6

7

Predict how many paper squares you would have next!

Think about it…

■ The activity modeled cell division (when one cell splits into two).❑ Why is it important for cells to divide?❑ How does a person get taller?❑ How does a broken bone heal itself?❑ Why do cuts and scrapes disappear?❑ What is the main purposes for cell division?

Topic : Cell Division - Mitosis■ Questions:

■ Why do cells need to divide?

■ Notes:■ 3 Reasons Cells Divide:

❑ Growth – So organisms can grow and develop.

❑ Maintenance – To replace worn out or dead cells.

❑ Repair – To fix cuts and scrapes and heal body parts.

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Topic : Cell Division - Mitosis

■ Questions: ■ Notes:■ Interphase: when cells grow

and copy their DNA.■ Cells spend most of their time in

interphase.■ Mitosis: When 1 cell divides

and becomes 2 cells.

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Topic : Cell Division - Mitosis■ Questions:

■ What are the stages of cell division?

■ Notes:■ Mitosis has 5 stages or phases:■ Cells begin in Interphase.■ Stage 1: Prophase ■ Stage 2: Metaphase■ Stage 3: Anaphase■ Stage 4: Telophase ■ Stage 5: Daughter cells

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Multiplying by Dividing Lab: Guided Activity.

■ Interphase:■ Stage 1: Prophase –

mitosis begins.

Nucleus

Multiplying by Dividing Lab: Guided Activity.

■ Stage 2: Metaphase – chromosomes line up in the middle of the cell.

■ Stage 3: Anaphase – chromosomes move to different sides of a cell.

Multiplying by Dividing Lab: Guided Activity.

■ Stage 4: Telophase – the cell begins to divide.

■ Stage 5: Daughter cells – 2 cells are created and go back to interphase.

2 new Nuclei

■ Outline the cell membrane of the cells in these colors:

■ Prophase cells—red■ Metaphase cells—green■ Anaphase cells—yellow■ Telophase cells—orange■ Interphase cells—purple

Multiplying by Dividing Lab: Guided Activity.

Cell Cycle – The Stages of Cell Division

Cell Division in a Plant’s Root

■ Why would you be able to see cell division occurring in a plant’s root tip?

Cell Division Wrap-up:

■ You should be able to answer these questions about cell division❑ Why is it important for cells to divide?❑ How does a person get taller?❑ How does a broken bone heal itself?❑ Why do cuts and scrapes disappear?❑ What is the main purposes for cell division?