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Flashcards in Mitochondria Deck (40)
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1
Q

What did mt. descend from?

A

Protobacteria

2
Q

Do mt have their own genome?

A

Yes

3
Q

How many mt proteins have been detected?

A

670 are imported and 13 are made from the mitochondrial genome

4
Q

How many proteins does the mt genome encode for?

A

13

5
Q

How many membranes does a mt have?

A

2

6
Q

What type of bacteria did mt. descend from?

A

Alphaprotobacteria

7
Q

What is contained within the mt.intermembrane space?

A

Cyt-c

8
Q

What is contained within mt. matrix?

A

TCA enzymes, PDH complex, beta ox enzymes, DNA, RNA, ribosomes, ATP,ADP,Pi, ions, etc.

9
Q

What controls ATP flux in mitochondria?

A

Cristae contacts with inner membrane

10
Q

Describe a mt. under active respiration.

A

Condensed matrix, expanded intermembrane space, proton pumping into intermembrane spacecauses water to follow and swells membrane

11
Q

What protein controls contact of cristae with mt. inner membrane?

A

Mitofilin-this is a test question almost 100% sure

12
Q

What are some apoptotic mitochondrial signals?

A

Bad, Bix, Bax, etc. causes mt. membrane to become leaky and form pores that cause cyt-c to leak and couple with Apaf-1 which results in a caspase cascade and cell death

13
Q

What structure does a porin have? What is the largest wt. molecule that can pass?

A

Beta barrel, 5kDa

14
Q

What is cardiolipin formed from?

A

Glycerol with 2 FA

15
Q

What portion of cardiolipin associates with mt. inner membrane?

A

Unsaturated FA

16
Q

If FA is not saturated then what can this cause?

A

Cardiomyopathy, barth syndrome

17
Q

Describe a mitochondrial carrier protein

A

Can carrier lots of small molecules, has structure with 6 transmembrane helices, antiporters , alternate conformations based on salt bridgeskinks formed by proline residues in active site, highly conserved structure

18
Q

What anion can damage almost any intracellular product? What reduces it?

A

Superoxide; superoxide dismutase

19
Q

What can convert hydrogen peroxide to oxygen and water.

A

Catalase

20
Q

What reduces hydroxyradical?

A

Vit C, Vit E

21
Q

How many e- does it take to get from oxygen to water?

A

4

22
Q

What proteins are found in the apoptisome

A

Cytacrome-C APAF-1 and Capase-9

23
Q

Mitochondrial functions include what?

A

TCA cycle, respiration, fatty beta oxidation, ammonia elimination via urea cycle, heme biosynthesis, protection against oxidative stress, RNA/DNA/protein biosynthesis, Mt biogenesis, molecular transport, calcium uptake/release

24
Q

What does the inner membrane hold?

A

inner membrane holds ETC and ATP synthase as well as set of carrier proteins required for exchange metabolites

25
Q

Describe active respiration wrt to ADP and what happens to the mitochondria?

A

-oxygen concentration drops rapidly until ADP runs out
-Mt changes appearance=>
Low [ADP]=> moves from condensed to expanded (orthodox)

High [ADP]=> moves from orthodox to condensed

26
Q

What protein in the Mt has been linking to cristae morphology and is part of the Mt inner membrane organizing system?

A

mitofilin

27
Q

Describe how Mt is important in apoptosis

A

B, B, B gives a pro-apoptotic signal that causes Mt to become leaky and release cytochrome c into the cytosol
-cytochrome c unites with Apaf-1 to recruit caspase 9 which form the apoptosome that triggers a caspase cascade for cell death

28
Q

What are caspases?

A

cysteine proteases that must be activated

29
Q

What is the protein that is significant in the outer membrane of the Mt?

A

porin

30
Q

What is the unique phospholipid in the inner membrane? What are the results if the protein is disrupted?

A

cardiolipin => Barth syndrome=> defective Mt, cardiomyopathy, muscle weakness

31
Q

What can move across the inner membrane easy?

A

water, oxygen, CO2

32
Q

ADP, ATP, phosphate, pyruvate, and other AA need special transporters are what?

A

mitochondrial carriers

33
Q

What helps to stabilize the different conformations of the Mt carriers?

A

charge pairs at the matrix membrane surface shift during the transport cycle

34
Q

What do diseases of Mt origin result in?

A

production of ROS

35
Q

What is the goal of respiration?

A

reduce oxygen to water and in the process to capture energy of electrons removed from pyruvate

36
Q

What happens to if one electron is added to oxygen? If the enzyme to eliminate this is not present, what will occur?

A

superoxide anion

oxidative stress linked to alzheimers, parkinsons, aging

37
Q

What occurs or is found in the Mt matrix?

A
  1. pyruvate DH complex
  2. citric acid cycle enzymes
  3. fatty acid oxidation enzymes
  4. AA oxidation enzymes
38
Q

As respiration increases, what happens to the christae in the IM space? What protein regulates this?

A

it increases its openness regulated by mitofilin

39
Q

ROS are needed for some of the proper insulin signaling. What will occur if this does not happen?

A

No ROS=> type II diabetes

40
Q

What 2 vitamins are important in scavenged for the hydroxyl radicals?

A

vitamin c and e