Lecture 17 Part 2

Question 1

What is the function of the mitochondria and chloroplasts

Answer 1

Mitochondria: ATP synthesis, apoptosis

Chloroplasts: photosynthesis, ATP synthesis

Question 2

What is aerobic respiration

Answer 2

Converts presence of oxygen energy stored in food molecules in to ATP

Produces carbon dioxide as a by-product

Question 3

What is the function of photosynthesis

Answer 3

Builds/makes carbs using energy from sunlight and carbon dioxide

Question 4

Where does aerobic respiration occur

Answer 4

The mitochondria

Question 5

What is the function of the outer mitochondrial membrane (OMM)

Answer 5

Contains enzymes with diverse metabolic functions

Contains porins (large channels permeable to many molecules when opened)

Question 6

What is the structure/function of the inner mitochondrial membrane (IMM)

Answer 6

High protein: lipid ratio (3:1)

Has cristae (double-layer folds) that increases surface area and contains machinery for aerobic respiration and ATP formation

Rich in cardiolipin (phospholipid) (in bacterial membranes, optimal function of enzymes)

Question 7

What are the 2 aqueous (gel like) compartments of the mitochondria?
What are their functions?

Answer 7

Intermembrane space: separates the OMM and IMM

Matrix: high protein content, gel like substance containing mitochondrial ribosomes and mitochondrial genome (DNA)

Question 8

What is substrate level phosphorylation

Answer 8

Hydrolysis reaction that releases enough energy to drive phosphorylation of ADP to ATP

Example: in glycolysis where 1 glucose to broken down into 2 pyruvates)

Question 9

What is oxidative phosphorylation

Answer 9

Chemical energy of organic molecules is transferred first to the electron carriers

Electron carriers create an electrochemical gradient that can power ATP synthesis

Question 10

What states do electron carriers exist as

Answer 10

Oxidative (accepts electrons): NAD+ and FAD

Reduced (donates electrons when returning to oxidized state): NADH and FADH2

Question 11

What is the first step in oxidative phosphorylation

Answer 11

Creating a electrochemical gradient:

electrons transport through complex’s and proton pumping

Height energy electrons pass from coenzymes (NADH and FADH2) in the matrix to election carriers in the IMM

Energy transfer at each complex pumps protons from matrix into intermembrane space

Low energy electron are transferred to final acceptor (O2) and produces H2O

Question 12

What is the second step in oxidative phosphorylation

Answer 12

Protons move down the electrochemical gradient to power ATP synthesis