mitosis asexual cell division!! begins in the nucleus of a cell
TRANSCRIPT
Mitosis
Asexual cell division!!
Begins in the nucleus of a cell.
How does asexual reproduction occur in humans?
• MITOSIS– Skin cells – Liver cells
MITOSIS1. Occurs in somatic
(body) cells.
2. Does not create sperm and egg.
3. Creates exact copies of a parent cell
4. Used to repair wounds and grow from a zygote to a person.
5. DNA duplicates itself and then the cell divides
MITOSIS
Mitosis and the Cell CycleRemember the letters: I P M A T
These letters will help you to remember the order of the 5 stages of the Cell Cycle:1. Interphase
1. Prophase
1. Metaphase
1. Anaphase
1. Telophase
Interphase:Called Resting phase
Cell is NOT dividing
Performs life functions
- Cell grows
- Copies all organelles
- Copies DNA
1. Interphase: “Prep Period”
- Cell preparation for cell division
- Two Major Events:
1. Cell increases in size
2. DNA and organelles
are replicated (copied)
Chromatin: are chromosomes when they are NOT distinguishable and they look like spaghetti.
Interphase has 3 parts (takes up about 90% of the cell cycle)
1. G1 - growth one phase (organelles grow)
2. S - synthesis phase (replication of chromosome material)
3. G2 - growth phase two (more organelle and cell growth)
MITOSIS- Has 4 phases - Prophase, Metaphase, Anaphase, Telophase
Prophase:- DNA changes from chromatin to chromosome
- Nucleus breaks apart with nucleolus and nuclear membrane disappears
- Centrioles begin to separate and move to poles
- Spindle fibers form to connect centrioles
Terms:• Chromatid: each chromosome strand
• Centromere: (kinetochore): holds the chromatids together
Metaphase: (M is for Middle)
• Chromosomes line up along the equator (middle)
• Chromosomes attach to the spindle fibers at their centromeres
Anaphase: ( A is for Away)• Spindle fibers pull chromosomes apart and
move each half of the chromosomes to opposite poles
Telophase: the reverse of interphase
• Nuclear membrane form around each set of chromosomes
• DNA changes from chromosomes to chromatin
• Spindle fibers disappear
Plant cells -
CYTOKINESIS
• the cell membrane pinches in to split the parent cell into two daughter cells.
Compare & Contrast Mitosis in Plants and Animals
Plant vs Animal
Plant Animal
No centrioles = no spindle fibers
Centrioles
No astray rays b/c there are no centrioles
Astray rays
Forms a cell plate Cytokinesis to pinch in cell membrane
Asexual Reproduction: Mitosis
•