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THE CELL CYCLE

NUCLEAR ENVELOPE CHROMATIN NUCLEOLUS NUCLEAR PORE

self-replication which is

essential for growth, asexual

reproduction (both mitosis)

and sexual reproduction

(meiosis)

alterations in the genetic code

(mutation) providing variation and

via natural selection, the basis for

evolution.

THE CELL CYCLE

https://www.youtube.com/watch?v=eTmibYv8ouw

Prophase

• (^) Replicated chromosomes coil up and contract (condensation) this prevents bits of DNA breaking away or getting tangled with other chromosomes.
• (^) Centrioles move to opposite poles of the cell.
• (^) Nuclear membrane breaks down.
• (^) Protein microtubules develop from each centriole, forming spindle fibres.

Anaphase

• (^) The centromere splits and sister chromatids separate.
• (^) They move to opposite poles of the spindle.
• (^) There are lots of mitochondria surrounding the spindle to provide it with the energy for

Telophase

• (^) Chromatids are at opposite poles of the cell.
• (^) A nuclear membrane forms around each set of chromatids.
• (^) Cytokinesis divides the cytoplasm into two cells along the equatorial line.
• (^) Chromatids uncoil.

Cytokinesis divides the cytoplasm and cell surface membrane into two cells along the equatorial line. This is not part of MITOSIS but happens simultaneously to TELOPHASE

WHICH STAGE OF MITOSIS?

WHICH STAGE OF MITOSIS?

WHICH STAGE OF MITOSIS?