Mitochondria

Question 1

endosymbiosis

Answer 1

how eukaryotes evolved
prokaryote grows
plasma membrane forms infoldings and pinches
engulfs aerobic bacterium

Question 2

consequences of endosymbiosis

Answer 2

as mitochondria where once own cells…
have own genome
have machinery to make RNA and proteins

Question 3

mitochondria genome

Answer 3

single circle chromosome
37 genes - 2rna 22trna 13 protein encoding
16500 base pairs

Question 4

mitochondria DNA production

Answer 4

fusion and fission to increase or decrease
replicates but random

Question 5

mitochondrial biogenesis

Answer 5

increased abundance of m proteins and mdna

Question 6

mitochondria ribosomes

Answer 6

55s
(large = 39s, 16s rrna, 50 proteins)
(small = 28s, 12s rrna, 30 proteins)

Question 7

mitochondria proteins

Answer 7

ribosomes used to created proteins encoded by mtdna

Question 8

signal sequence

Answer 8

in the protein telling it where to go

Question 9

transport proteins in mitochondria

Answer 9

signal sequence binds to import receptors
insertion into membrane by TOM complex
translocation into matrix by TIM complex
leverage by signal peptidase

Question 10

transport pyruvate into mitochondria

Answer 10

outer membrane has porins
allow small (up to 5000 Da) inside = pyruvate passes in
moved into matrix by mitochondrial pyruvate carriers
decarboxylated = acetyl co a

Question 11

transport fatty acids into mitochondria

Answer 11

fatty acetyl co a binds to CPT 1 which moves through outer membrane
acyl-camitine moves through translocase into matrix
binds to CPT 2 releasing camitine
camitine moves back through translocase (anti port active transport)

Question 12

transport NADH into mitochondria

Answer 12

NADH oxidised & malate forms
malate passes into matrix in return for ketoglutarate
malate oxidised and NADH reformed