Meiosis

Cell produced = gamete (sperm and ova)

Each gamete is gentetically different

Diploid cell (has full set of chromosomes) divides into four halpoid cells (half the genetic material)

• Interphase I
• Prophase I
• Metaphase I
• Anaphase I
• Teolophase I
• Prophase II
• Metaphase II
• Anaphase II
• Telophase II

The resting phase

- DNA replication takes place

Crossing over takes place

- Homologus pairs of chromosomes line up

- Duplicated chromosomes become entangled and swap/crossover

Allows for an exchange of genetic material

Provides genetic variations

Centrioles begin to move to opposite poles

Nuclear envelope begins to break down

Spindle fibres from centrioles attach to chromosomes/centromeres

They pull the chromosomes to the centre

Spindle fibres shorten

- The chromotids do not separate

- Chromosomes move to the poles

Spindle fibres break down

Two diploid cells

Still no nuclear membrane

DNA already replicated

Centiroles move to opposite poles

Spindle fibres attach to centromeres

Pull the chormosomes to the centre

Spindle fibres shorten

Pulls the chromotids apart

Spindle fibres break down

Nuclear membrane forms in each new cell

4 halpoid daughter cells - half the number of chromosomes as parent cells

Not identical to parent cells