Cell cycle

Tues

What is cell division for reproduction?

binary fission in bacteria

What does cell division mean in the cell cycle?

New cells arise from pre-existing cells = cell division, part of cell cycle

: What is the cell cycle?

cell growth + division of the nucleus and genetic material (mitosis), cytoplasm and organelles (cytokinesis)

What happens to DNA prior to cell division?

Prior to cell division DNA is replicated but the genetic material can then divide in two very different ways

How does mitosis divide genetic material?

Mitosis: genetic material is copied and divided equally so “daughter” cells are genetically identical to the “parent” cell

How is the cell cycle regulated

Cell cycle is tightly regulated (molecular checkpoints)

What does breakdown of cell cycle control lead to?

cancer

What is the M- (mitotic) phase?

= dividing phase (mitosis + cytokinesis)

What is the I- (interphase) phase?

non-dividing phase

What occurs during all three I-phases?

Cell growth occurs in all 3 I-phases; including replication of all cell organelles/membranes

When does DNA replication occur?

DNA replication occurs in S-phase, i.e. chromatin is copied

What is DNA replication?

making a copy of DNA, using DNA as a template and using DNA nucleotides

What is transcription?

making an mRNA copy of a DNA template, using RNA nucleotides

What is translation?

making a protein, using an mRNA template and amino acids

tell me about what happens in S phase

. centrosome copy . DNA replication

Prophase?

Chromatin to chromosomes, Miotic spindle starts to form, Centrosomes start moving away.

Prometaphase?

Nucleur envelope dissolves, kinetochore microtubules contact chromosomes at kinetochore

Metaphase?

Chromosomes line up flat in the middle, miotic spindle fully forms

Anaphase?

sister chromatids separate - pulled to opposite poles and microtubules get shorter

Telophase?

nuclear envelope reforms, spindle disintegrated/ chromosomes to chromatin

Cyto kinesis ?

via cleavage- contractile ring of actin microfilliment and myosin interact with it to contract ring - drawstring

Everything about MPF??

voice…

All Checkpoints?

voice

Other regulative signals?

Voice

How do chromosomes move?

voice

Mitotic Spindle

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