Mitochondria And Ribosomes Flashcards
What is the difference between the cytosol and cytoplasm?
Cytoplasm is all material bar nucleus enclosed by cell membrane
Cytosol is the aq portion of the cytoplasm
Describe the structure of the mitochondria
Eg. membrane, mobility, associations
Mitochondria have a double membrane
Mobile organisms that change shape and position
Associate with multiple microtubules of cytoskeleton demines orientation and distribution
What is the outer mitochondria membrane permeable to ?
5KDa or less molecules and ions
Name 6 parts of the mitochondria structure
Outer membrane Inner membrane Intermembrane Space Electron Transport Chain Matrix Mitochondrial DNA
What does the inner membrane contain?
Contains Cristae containing proteins for ETC
Selected ions, protons and phosphates can pass via transport proteins
Others pass via diffusion barrier
What are the 2 types of mitochondrial fission and how do they differ?
Midzone fission- division to replicate
Peripheral Fission =get rid of damaged material
Describe Stage 1 of chemiosmosic coupling
High Energy electrons (derived from oxidation of food)
are transferred along a series of electron carriers in the membrane
The transfers release energy which is used to pump H+ across membrane
This creates a protein gradient and involves 4 protein complexes
At the end 2 electrons reduce oxygen to H2O
Describe Stage 2 of chemiosmotic coupling
Proton gradient provides energy store to drive ATP synthase
ADP +Pi- ATP
Carbs and fats are broken down releasing high energy electrons
2 electrons picked up by NAD+ creating NADH
this carries electrons to inner mitochondrial membrane
Glycolysis converts glucose to pyruvate
In mitochondria pryruvate is oxidised by O2 producing CO2 and H2O plus 15 atp molecules
In mitochondria what oxidises pyruvate and what are the products?
In mitochondria pryruvate is oxidised by O2 producing CO2 and H2O plus 15 atp molecules
What is mtDNA or mDNA
Mitochondrial DNA
How many bases in mDNA in humans
How many proteins does this code for?
1659 bases
Encodes 13 proteins
Why is mDNA uses in phylogenetic studies?
It evolves faster than human DNA
mDNA is mostly inherited from the mother or the father?
Mother
What is the size and subunits of the Prokaryotic ribosome?
70S
50S large subunit and 30S small subunit
What is the size and subunits of the Eukaryotic ribosome?
80S
60S large subunit
40S small subunit
What does the S stand for in relation to the subunits?
S=Svedberg units
Rate of precipitation when centrifuged
hence the larger the subunit the faster it precipitates
Name the 3 binding sites on a ribosome and what occurs at which?
mRNA binding site
A-site binding of aminoacyl tRNA
P-site binding of the most recent amino acid
E-site/exit site of deacylated tRNA
Where is the A-site P-site and E-site?
On the ribosomes large subunit
Where is the mRNA binding site?
On the ribosomes small subunit
What does RIP stand for?
Ribosomes Inactivating Proteins
What are the 2 types of RIP and how do they differ?
Type I cannot cross the cell membrane and not cytotoxic
Type II has a binding domain allows entry of the toxin into the cells crossing the plasma membrane
