Mitochondrial Genetics

Question 1

eukaryotes have cell organelles which are part of the _____ system

Answer 1

endomembrane

Question 2

not so well known organelles

Answer 2

secretory vesicles

lysosomes

peroxisomes

nucleus

Question 3

which eukaryote organelles are autonomous?

Answer 3

mitochondria (in all eukaryotes)

chloroplasts (in plants)

Question 4

autonomous cell organelles have their own ___

Answer 4

genomes

protein-synthetic machinery

Question 5

can autonomous cell organelles divide on their own?

Answer 5

yes

Question 6

if autonomous cell organelles are lost can the cell replace them?

Answer 6

no

Question 7

where do autonomous cell organelles come from?

Answer 7

relics of independent bacteria that became internal symbionts (endosymbionts) in eukaryotes

Question 8

are mitochondrion genomes large?

Answer 8

no, very small because they have lost most of their genes

the genes migrated into the cell’s nucleus

non-essential genes were eliminated

Question 9

mitochondrial DNA

Answer 9

genomes are circular and very small

size varies with the complexity of the eukaryote

Question 10

largest known mtDNA genome

Answer 10

from a protozoan with ~97 genes

Question 11

smallest known mtDNA genome

Answer 11

from a mammal with 37 genes

Question 12

mammalian mitochondrial genomes (including humans) only code for ___ genes

Answer 12

37

Question 13

how many mammalian mitochondrial genes code for proteins?

Answer 13

13

the rest are tRNA (22) and rRNA (2)

Question 14

differences in gametes in terms of mitochondria

Answer 14

egg is huge and has many more mitochondria

head of sperm has many mitochondria

Question 15

zygote takes mitochondria from the ….

Answer 15

egg

not the sperm

Question 16

mitochondrial transmission is ___

Answer 16

non-Mendelian inheritance

Question 17

mitochondria are transmitted through the ____ parent

Answer 17

female

doesn’t recombine every generation so provides a tracer down the family tree

Question 18

can mitochondria have genetic problems?

Answer 18

yes

either from defective mitochondrial genes

or from defective nuclear genes that affect the mitochondrion

Question 19

can mutations affect the mitochondria?

Answer 19

yes, but there are not in the germline so not passed on

Question 20

3 sources of mitochondrial disease

Answer 20

inherited mutation in nuclear genes that code for mitochondrial proteins

inherited mutations in mitochondrial genes

somatic mutations in mitochondrial genes

Question 21

3 possible transmission patterns of mitochondrial traits

Answer 21

mendelian inheritance

non-mendelian inheritance

no inheritance