Mitosis One pager

What is the basis of cell divsion

organisms are able to reproduce

Cell divison overall idea and process

when one cell becomes two

DNA is replicated in the orginal cell and each new cell recieves one copy of the DNA

Unicellular organisms reproduction and examples

Produce a whoel new organism that is genetically identical

• Yeast, Bacteria, Protists

Asexual reprodution idea and examples

Only one organism is needed to Produce a genetically identical offspring

Starfish, plants

3 reasons why cells need to divde

1. Growth and devleopment

2. Replace damaged cells

3. Produce gametes for sexual reporduction

2 types of cell divison

Mitosis and Meiosis

Mitosis goal

Make a genetically identical copy of a cell

DNA of orgainl cell msut be copied

What is a parent cell

Orginal cell

What is daughter cell

The resulting two cells durign mitosis

Define chromosomes

DNA divded into indiviudual segments

Define Histones

Protein complexes that DNA is wrapped around. Helps compact DNA into chromosomes

What does a chromosomes look like

An X

How many chromosomes does each cell in a human have

23 pairs (22 autosomes and 1 sex chromosomes)

Define diploid organism

Organisms that have 2 copies of each chromosome in the cell

Define centromere

how duplicated chromosomes stay attached to the orginal

where sister chromatids connect

Define sister chromatids

The duplicates —> Will soon be split up into two new cells

What is replicated during mitosis

Chromosomes

Pitchure of replicating chromosome

2 chromatids (each half of the chromosome) are duplicated to form 2 chromosomes

Where do we get two copies of chromosomes

one from each of our parents

4 stages of Mitosis cycle

G1

S

G2

M

what does interphase include

G1, S, G2

How do prokaryotes reproduce

1. Chromosomes are duplicated

2. Copies are separated

3. Cell elongates

4. Cells are divided into two daughter cells

G1 basic idea

Growth phase 1 that gets the cell ready for divsion

S basic idea

Synthesis phase refers to the duplcaiting of DNA

G2 basic idea

S phase uses alot of energy so growth pahse 2 gives the cell a chance to rebuild its energy supply

M basic idea

Mitotic phase, the actual division of the cell

G1 phase explained

We want the daughter cells to be the same size as the parent cell. The cell must grow in size for this to happen

Enzymes and proteins for cell divison are also made here

Synthesis Phase expalined

DNA replication that uses alot of ATP

G2 phase explained

Cells must rebuild their energy supply before proceeding to M phase

Also checks to make sure all DNA was replicated

Microtubules

Orginate from centrosomes as they migrate to opposite sides of the cell

These attach to the sister chromatids

Kinetochore protiens

Connects both the sister chromatids and microtubules originating from the centrosomes

Six steps of Mitosis

1. Prophase

2. Prometaphase

3. Metaphase

4. Anaphase

5. Telophase

6. Cytokinesis

   Polly Pocket Met A Toy Cat

Metaphase plate

Line of chromosomes in metaphase plate

Mitosis

Where one cell becomes two

• 6 stages

Prophase

DNA is condensed

Centrosomes start to migrate

Prometaphase

Nuclear envelope completely breaks down

Chromosomes are exposed in the cytoplasm

Centrosomes are now on exact opposite sides of the cell

Metaphase

All duplicated chromosomes are arranged in the middle of the cell by the action of the mitotic spindle and microtubules

Each sister chromoatid of duplcaited chromosomes faces one of the centrosomes

Anaphase

Sister chromatids are pulled apart and carried to the centrosomes on opposite sides of the cell

Telophase

Separated sister chromatids and sequestered at opposite sides of the cell.

New nuclei begin to envelope the chromosomes

Cytokensis

Splitting of the cell

Diffrent in plants and animals

Cytokensis in animal cells

Cleavage furrow that pinches the new cells apart

Cytokenesis in plants

A new plant wall is built using vesicles

Mitotic cell cycle checkpoints

G1 checkpoint

G2 checkpoint

Metaphase checkpoint

G1 checkpoint

Waiting for all clear to divide

Checks for:

• Nutrients

• Growth factors

• DNA damage

IF problems are found the cell will be sent to G₀

located at end of G1

G2 checkpoint

Checks for Cell size and if the DNA replcaited

Located at end of G2

Metaphase checkpoint

Within mitoic phase

Checks for chromosome spindle attamenent

What could happen if the G1 checkpoint was messed up

Damaged DNA could be replicated and produce daughter cells with damaged DNA

What could happen if the G2 checkpoint was messed up

If DNA is not fully replicated than one of the daughter cells will be missing DNA that will most likly kill the cell

What could happen if the Metaphase checkpoint was messed up

if chromosomes are not attached to the spindle properly then each daughter cell could inherit diffrent number of chromsomes

Cell reproduction life cycle picture

G1 is the longest