Human Genome Flashcards
Central dogma
DNA -> RNA in nucleus -> RNA in cytoplasm -> protein
What does a chromosome have
It has a centromere and telomere
Which genome the mitochondrial Genome or the nuclear genome has more base pairs
Nuclear genome
What causes genetic variation
Change in 1 base pair
How does a phenotype get to being expressed
Genotype -> Development -> Phenotype
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Environment
What does a DNA polymer have
A nucleotide phosphate and deoxyribose sugar
DNA Base pairs
GCAT
Which direction is DNA replicated
5’ to 3’ strand
C and G are joined by
3 carbon bonds
A and T are joined by
2 carbon bonds
What are DNA strands joined by
Hydrogen bonds
What does DNA form
A double helix and a sugar phosphate backbone
How is DNA packaged
The chromatin compact by interacting with the nucleosome which is then further coiled into a chromosome
How many base pairs does the chromatin and nucleosome wraps around whilst compacting
146
How is DNA replicated
DNA helicase causes double-stranded DNA to unwind then RNA binds to unwound DNA – DNA polymerase requires RNA as a primer
DNA polymerase only acts in what direction
From the 5’ to 3’ direction so causes lagging strand to do discontinuous replication
Stages of mitosis
Prophase, metaphase, anaphase, telophase
IPMAT
What happens in metaphase
Centromere go to each side, microtubules attach to 1/2 of chromosome and the chromosomes line up in the middle
What happens in anaphase
Chromosomes are pulled apart by microtubules
What happens in telophase
New nuclear membrane is regenerated
Stages of cell cycle
G1 resting stage-Here non-dividing cells arrest at this stage G0 S Stage- DNA synthesis G2 resting stage Mitosis Cytokinesis
Cell cycle checkpoints
G1- check DNA isn’t damaged
S & G2- DNA damages or incompletely replicated
M- chromosome not attached to mitotic spindle
Cell cycle checkpoints controlled by
Cyclins and protein kinsases
Chemotherapy targets which stages of the cell cycle
S and M
