mitosis1.notebook

1

November 08, 2011

Oct 30­11:52 AM

Monday, November 7Bell Work:

What would you do if you had to fit a lot of clothes into a small suitcase?  What if you were sharing the suitcase with your twin, what would you need to do?

Nov 4­8:02 AM

nucleotidesSugarPhosphate GroupNitrogen base

Chromatin

46

3 meters long

condense

interphasespaghetti DNA

mitosis1.notebook

2

November 08, 2011

Nov 4­8:02 AM

organizationfunctions

Proteins genes

chromosomesdivided nuclei

entangled

A cell could get 2 copies of a chromosomeA cell could get no copies of a chromosome

Nov 4­7:57 AM

mitosis1.notebook

3

November 08, 2011

Nov 4­8:00 AM

A group of proteins that DNA wraps around at regular intervals compacting DNA

The DNA is not organized into tightly compacted structures, it is loose.

A chromatid is one half of a duplicated chromosome, two identical chromatids together are a sister chromatid.

CentromereTelomeres are repeating nucleotides that contain no genes, this is important because it prevents the ends from sticking together and if any DNA is accidently lost, no genes are lost.

If a gene is lost, that person will not be able to produce that protein. This could cause mutations or impairments.

Oct 30­2:41 PM

Prophase

­longest stage of mitosis

­Long, stringy chromatin coil up into visible chromosomes.

1. At the beginning of prophase the nucleus begins to disappear.­nuclear envelope and nucleolus disintegrate.

2. In animal cells, centrioles begin to migrate to opposite ends of the cell and spindle fibers begin to form.

Sister chromatids

Centromere

Animal Cell Plant Cell

mitosis1.notebook

4

November 08, 2011

Oct 30­2:42 PM

Metaphase

1. Chromosomes attach to the spindle fibers by the centromere.

2. Line up on the equator of the cell.

3. Each sister chromatid is attached to its own spindle fiber.

4. One sister's chromatid spindle fiber extends to one pole and the other to the opposite pole.

5. Important because it ensures each new cell receives an identical and complete set of chromosomes.

Oct 30­2:42 PM

Anaphase

1. Centromeres split apart and the chromatid pairs from each chromosome separate.

2. Pulled to opposite poles.

3. Chromatids are pulled apart by the shortening the spindle fibers.

mitosis1.notebook

5

November 08, 2011

Oct 30­2:42 PM

Telophase

1. Nuclear membranes start to form.

2. Chromosomes unwind.

3. Spindle breaks down.

4. Cytokinesis begins

Oct 30­3:09 PM

Cytokinesis

Cytokinesis­ Division of cytoplasm.

Occurs near the end of telophase. 

Animal cells:  The plasma membrane pinches in along the equator and the cells divide.

Plant cells: A cell plate is laid down across the equator. A plasma membrane forms around each cell and a new cell wall forms on either side of the plate until separation is complete.

mitosis1.notebook

6

November 08, 2011

Oct 30­3:24 PM

Important:  Not all cells undergo mitosis.  

­Mature roots, leaves and stems of plants

­Nerve cells and adult bone cells

Single­celled organisms use mitosis to reproduce.

Multicellular organisms use mitosis for growth, development and repair.

Oct 30­3:26 PM

mitosis1.notebook

7

November 08, 2011

Oct 30­3:31 PM

Oct 7­4:28 PM