MEIOSIS 1: (8 Million possibilities)

The cell is just living its life

The nucleus opens up
The chromosomes from the dad and the mom move together and mix and match

The centrosomes and microtubules split apart the chromosomes

The chromosomes start to be split apart, but the chromatids aren’t separated.
It is the whole chromosomes that are being moved apart.

The chromosomes start to fold out / Unravel into their chromatin state.
The nucleus starts to form.
The microtubules dissolve.

Basically just mitosis.

Interphase 2:
Usually doesn’t happen, but does exist in some species.

Prophase 2:
The chromosomes are created.
The nucleus membrane is DESTROYED.

Metaphase 2:
The chromosomes are lining up in the middle of the cell.
The centrosomes are on OPPOSIDE sides of the cell.
The Centrosomes push away and pull a chromatid to each of them, AKA they pull the chromosomes apart.

Anaphase 2:
The chromatids are being pulled apart into FOUR separate chromosomes.

Telophase 2:
The chromosomes start to unwind and nuclear membranes are being created.

Meiosis: the chromosome count is halved 0.5x

Mitosis: the chromosome count is doubled 2x

This happens in Germ Cells which are located in the gonad’s

The big difference between meiosis and mitosis:
Chromosomes touch each other in synapsis but form a tetrad (bivalent) bond.

Crossing over happens after that, where genes are exchanged so the new chromosomes are now weird

The metaphase plate: the middle of the cell

In Meiosis 2, the chromosomes DO NOT replicate, they just stay the same.

Cleavage Furrow:
The separation of cells after division.

The Law of Independent assortment:

The chromosomes align in the middle randomly in metaphase.
There are 2^n possibilities in this phase, so 2^23 for humans.
(This DOES NOT take crossing over into a count, which basically makes it infinity).

Crossing Over:
Apart from the law of independent assortment, which is that genes are recombined.