2.2 Cell Division Flashcards
What is interphase?
(G1) cell growths and new organelles and proteins are made and energy stores increased
(synthesis) DNA is replicated
(G2) Cell keeps growing and proteins for division are made
What is Prophase?
Nuclear envelope breaks down
centrioles move to opposite poles of the cell
spindle fibres form
chromosomes condense.
What is metaphase?
chromosomes line up at the equator
spindle fibres attach the centromere to the centriole
What is anaphase?
The centromeres divide, splitting the sister chromatids
the spindles contract pulling the chromatids by there centromere to opposite poles
What is Telophase?
Chromatids move to opposite poles and unwind, becoming chromosomes again
nuclear envelope reforms around to create 2 nuclei
the cytoplasm splits in cytokinesis
there are 2 genetically identical cells
How do viruses replicate?
They do not. They inject RNA into their host cells as they’re non living
How do bacteria replicate?
BINARY FISSION
Circular DNA and plasmids replicate (circular once, plasmids many times)
DNA loops move to opposite poles, bacteria cell swells
cytoplasm divides
full cell walls are created
there are now 2 bacteria
What is a chromosome?
Long strands of genetic information. Two sister chromosomes joined at centromere
What is a homologous pair?
Chromosomes have pairs, 1 maternal and 1 paternal which are the same size and have the same location of alleles
What is a centromere?
Point on a chromosome which attaches chromatids or spindle fibre
What is an allele?
Same gene on different chromosomes
Gene
codes for proteins and characteristics
What is a centriole?
Organelles which produce spindle fibre
What is spindle fibre?
Protein which join to to centromere and contracts to pull chromosomes apart
What is uncontrolled Cell division?
Leads to cancers and tumours
