Mitochondrial Genetics Flashcards
eukaryotes have cell organelles which are part of the _____ system
endomembrane
not so well known organelles
secretory vesicles
lysosomes
peroxisomes
nucleus
which eukaryote organelles are autonomous?
mitochondria (in all eukaryotes)
chloroplasts (in plants)
autonomous cell organelles have their own ___
genomes
protein-synthetic machinery
can autonomous cell organelles divide on their own?
yes
if autonomous cell organelles are lost can the cell replace them?
no
where do autonomous cell organelles come from?
relics of independent bacteria that became internal symbionts (endosymbionts) in eukaryotes
are mitochondrion genomes large?
no, very small because they have lost most of their genes
the genes migrated into the cell’s nucleus
non-essential genes were eliminated
mitochondrial DNA
genomes are circular and very small
size varies with the complexity of the eukaryote
largest known mtDNA genome
from a protozoan with ~97 genes
smallest known mtDNA genome
from a mammal with 37 genes
mammalian mitochondrial genomes (including humans) only code for ___ genes
37
how many mammalian mitochondrial genes code for proteins?
13
the rest are tRNA (22) and rRNA (2)
differences in gametes in terms of mitochondria
egg is huge and has many more mitochondria
head of sperm has many mitochondria
zygote takes mitochondria from the ….
egg
not the sperm
mitochondrial transmission is ___
non-Mendelian inheritance
mitochondria are transmitted through the ____ parent
female
doesn’t recombine every generation so provides a tracer down the family tree
can mitochondria have genetic problems?
yes
either from defective mitochondrial genes
or from defective nuclear genes that affect the mitochondrion
can mutations affect the mitochondria?
yes, but there are not in the germline so not passed on
3 sources of mitochondrial disease
inherited mutation in nuclear genes that code for mitochondrial proteins
inherited mutations in mitochondrial genes
somatic mutations in mitochondrial genes
3 possible transmission patterns of mitochondrial traits
mendelian inheritance
non-mendelian inheritance
no inheritance
