Lecture 15: Oxidative Phosphorylation Flashcards
How do mitochondria adjust to their environment?
Mitochondria will move around, divide and change shape to fit the energy needs of their environment.
Where does oxidative phosphorylation take place?
On the inner membrane of the mitochondria. Transporting H+ to the intermembrane space.
What are the characteristics of the mitochondrial genome?
16.5Kbp in mitochondrial DNA.
It has histone proteins but is not condensed around them.
Double stranded.
Forms a ring.
Why is mitochondrial DNA more at risk for damage?
Because of how close mtDNA is to the process of oxidative phosphorylation and reactive oxygen species, plus the fact that mtDNA replicates faster than normal DNA and has less protection from histones as it is not tightly wound around them.
What are the differences in codons between mitochondrial DNA and nuclear DNA?
UAA, UAG and UGA are stop codons in non-mitochondrial DNA.
In vertebrate mtDNA, AGA and AGG are stop codons as well as UAA and UAG.
UGA, however, codes for tryptophan.
AUA codes for isoleucine in most organisms but in mtDNA it codes for methionine.
AUA and AUG are the two methionine (start) codons.
