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Flashcards in Mitochondria Deck (40):
1

What did mt. descend from?

Protobacteria

2

Do mt have their own genome?

Yes

3

How many mt proteins have been detected?

670 are imported and 13 are made from the mitochondrial genome

4

How many proteins does the mt genome encode for?

13

5

How many membranes does a mt have?

2

6

What type of bacteria did mt. descend from?

Alphaprotobacteria

7

What is contained within the mt.intermembrane space?

Cyt-c

8

What is contained within mt. matrix?

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

9

What controls ATP flux in mitochondria?

Cristae contacts with inner membrane

10

Describe a mt. under active respiration.

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

11

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

Mitofilin-this is a test question almost 100% sure

12

What are some apoptotic mitochondrial signals?

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

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

Beta barrel, 5kDa

14

What is cardiolipin formed from?

Glycerol with 2 FA

15

What portion of cardiolipin associates with mt. inner membrane?

Unsaturated FA

16

If FA is not saturated then what can this cause?

Cardiomyopathy, barth syndrome

17

Describe a mitochondrial carrier protein

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

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

Superoxide; superoxide dismutase

19

What can convert hydrogen peroxide to oxygen and water.

Catalase

20

What reduces hydroxyradical?

Vit C, Vit E

21

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

4

22

What proteins are found in the apoptisome

Cytacrome-C APAF-1 and Capase-9

23

Mitochondrial functions include what?

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

What does the inner membrane hold?

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

25

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

-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

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

mitofilin

27

Describe how Mt is important in apoptosis

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

What are caspases?

cysteine proteases that must be activated

29

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

porin

30

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

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

31

What can move across the inner membrane easy?

water, oxygen, CO2

32

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

mitochondrial carriers

33

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

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

34

What do diseases of Mt origin result in?

production of ROS

35

What is the goal of respiration?

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

36

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

superoxide anion

oxidative stress linked to alzheimers, parkinsons, aging

37

What occurs or is found in the Mt matrix?

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

38

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

it increases its openness regulated by mitofilin

39

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

No ROS=> type II diabetes

40

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

vitamin c and e