Mitosis and Meiosis

Lecture notes

Use the links below for additional information on mitosis and meiosis.

Mitosis

Meiosis

Mitosis in Animals

Human Chromosomes

1. View a slide of human chromosomes and draw some of the chromosomes in your notebook.

2. Do the chromosomes have one chromatid or two?

Below: Human Chromosomes Click on the photograph to view an enlargement.

Whitefish Blastula

3. The cells of a developing embryo are dividing rapidly and can be used for viewing the different stages of mitosis. Obtain a whitefish blastula (early embryo) slide and find a cell in each of these phases: interphase, prophase, metaphase, anaphase, and telophase.

4. Draw a cell in anaphase.

Mitosis in Plants

5. Cells at the tips of plant roots and stems grow rapidly and can be used for viewing the stages of mitosis. Used a slide of onion (Allium) root tip to identify interphase, prophase, metaphase, anaphase, and telophase.

6. Find a cell in telophase and draw the cell in your notebook. Draw the cell plate if it is visible.

Meiosis in Animals (Gametogenesis)

Testis

7. Obtain a slide of a cross section of cat testes and observe the seminiferous tubules. Identify spermatogonia. Identify sperm.

Below: Rat testes X 100. Click on the image to view an enlargement.

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Ovary

The primary oocyte is contained within a structure called a follicle. As the follicle enlarges, it produces hormones. During ovulation, the follicle ruptures and releases the secondary oocyte

8. View a slide of a section of a rabbit ovary under scanning magnification and observe follicles in various stages of development. Can you see an oocyte in any of the follicles?

Below: Rabbit ovary X 40. Click on the image to view an enlargement.

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