Unit 1: cells and proteins KA 1.5: protein control of cell division Flashcards
What is the cytoskeleton made of?
A polymer called microtubules. These are composed of protein monomer called tubulin.
name the structure microtubules form during cell division
spindle fibres
name the monomer that forms microtubules
tublin monomer
where do the microtubules radiate from in the cell?
Microtubule organising centre (MTOC) also known as the centrosome
The cell cycle can be divided into two parts what are their names?
interphase and mitotic (M) phase
Function of mitosis
provides new cells for growth repair of damaged tissues and replacement of dead or damaged cells.
It also maintains the cells diploid chromosome complement.
function of interphase
growth and DNA synthesis including-
G1-a growth phase
S phase-during which DNA is replicated and
G2-a further growth phase
what is the acronym for the mitotic phase?
PMAT
What happens in prophase?
DNA condenses into chromosomes each consisting of two sister chromatids
nuclear membrane breaks down
spindle microtubules extend from the MTOC by polymerisation and attached to chromosomes to be their kinetic course in the centromere region
what happens in metaphase?
Chromosomes are aligned at the metaphase plate (equator of the cell)
what happen anaphase?
A spindle microtubules shortened by T polymerisation chromatids are separated and chromosomes are pulled apart to the opposite poles
what happens in Telophase?
The chromosomes de condense and the nuclear membrane are formed around them
What happens in cytokinesis?
The cytoplasm is separated into two daughter cells
what is checked for at the G1 checkpoint?
DNA damage, growth factors and nutrients
what is checked for at the G2 checkpoint?
DNA replication and cell size
