Warm ups:1. List the four steps of mitosis – in order.

2. Explain the end results of mitosis…a. are the cells different or identical to the parent cell,b. what types of cells go through mitosis,c. how many cells do you start with, d. how many cells do you end up with, e. How many cell divisions happen, andf. What is the type of cell you end up with? (haploid or

diploid)

Itinerary:1. Meiosis notes2. Meiosis Video 3. Meiosis animations4. Meiosis drawing worksheet

Meiosis Notes

Objectives: 1. To differentiate between mitosis

and meiosis 2. To explain the 8 steps of Meiosis

and explain what happens in each step

Meiosis – Cell division that creates sex cells.

1. Nucleus divides 2 times2. Produce sex cells (sperm and egg) with exactly half

of the chromosomes of the parent cell3. Only happens to make cells for sexual reproduction

(Oh my! “meiosis”)

Steps of Meiosis are broken down in two parts: Meiosis I and Meiosis II

Meiosis I: similar to steps of mitosis

1.) Prophase I – chromosomes already copied, nuclear membrane disappears2.) Metaphase I – chromosomes line up in pairs in middle of cell3.) Anaphase I – chromosome pairs separate4.) Telophase I – cells pinch in

Meiosis II

1.) Prophase II – chromosomes do not copy2.) Metaphase I – chromosomes line up in pairs (in middle)3.) Anaphase I – chromosome pairs separate4.) Telophase I – cells pinch apart, nuclear membrane forms

You end up with 4 cells, with half the number of chromosomes!

Why is meiosis important?1. It makes sexual reproduction possible

GETncm/justsaycust-recrate-itemcommunittg/stores/dtg/stores/d-favorite-listruejust-say-no

Cell DivisionMitosis Meiosis

Makes Body Cells – “my – toe – sis”

Makes Sex Cells – “Oh my” myOsis)

New cells = Same number of

chromosomes (Diploid)

New cells = Half number of

chromosomes (Haploid)

Creates 2 cells Creates 4 cells

1 cell division 2 cell divisions

Exit slip1. What type of cells does mitosis make?

2. If a cell has 10 chromosomes and goes through meiosis, how many chromosomes will the new cells have?

3. What process makes new body cells?

4. What process makes reproductive cells?

5. What is the study of heredity called?