Genetics Mitosis

In eukaryotic cells, the genetics information that is passed on from one generation to the next is carried by chromosomes.

Cell Cycle Chromosomes are made up of DNA(genetic material) wrapped in proteins and they are found in the nucleus.

Chromosomes are not visible in most cells except during cell division Chromosomes are not visible in most cells except during cell division. Before cell division occurs, each chromosome is replicated or copied.

Because of this, each chromosome consists of two identical sister chromatids.

These chromatids are joined in the middle by the centromere These chromatids are joined in the middle by the centromere. When the cell divides, each of the “sister” chromatids separate from each other and one chromatid goes to each of the two new cells.

Mitosis is the process during cell division in which the nucleus of a cell is divided into two nuclei.

At the end of mitosis each nucleus has the same number of chromosomes as the original cell

The products of mitosis are 2 identical daughter cells that are equal in size, have identical copies of chromosomes, and half the cytoplasm and organelles. For example, if a skin in frogs has 20 chromosomes and it undergoes mitosis, both daughter cells will have 20 chromosomes.

Mitosis has four steps and it is followed by cytokinesis (division of cytoplasm)

Mitosis

Mitosis 1. Prophase-chromosomes become visible and the spindle forms

Mitosis 2. Metaphase-chromosomes move to the center of the cell and line up along the equator

Mitosis 3. Anaphase-centromeres divide and the two chromatids move to opposite poles attached to spindle fibers

Mitosis 4. Telophase-nuclear envelope forms around the chromosomes at each pole, the chromosomes uncoil, and the spindle dissolves

Mitosis

Mitosis Mitosis in plants and animals is slightly different. For example, in animal cells the cytoplasm is pinched and separated during cytokinesis and in plants a cell plate forms to separate the cytoplasm.

Mitosis

Mitosis

Mitosis

Mitosis

Mitosis

Mitosis-frog cell

Mitosis

Mitosis

Review What are the four stages of mitosis in order?

Review Prophase-Metaphase-Anaphase-Telophase

Review The division of the cytoplasm is called…

Review cytokinesis

Review What stage of mitosis is this?

Review Anaphase

In which stage of mitosis do the chromosomes become visible?

prophase

How is cytokinesis different in plant and animal cells?

Plants form a cell plate, animal cells pinch apart

PMAT Hand Signals P- plump M- middle A- apart T- two