Lecture 12

Question 1

Electron Transport Chain

Answer 1

couples electron transfer between an electron donor and an electron acceptor with the transfer of H+ ions across a membrane

Question 2

Terminal Electron Acceptor (TEA)

Answer 2

A compound that accepts an electron during oxidation of carbon sourc

Question 3

Electron Carrier

Answer 3

A molecule capable of accepting one (or more than one) electrons from another molecule (electron donor), and then ferry these electrons to donate to another during the process of electron transport.

Question 4

NAD

Answer 4

a coenzyme found in all living cells. The compound is a dinucleotide, since it consists of two nucleotides joined through their phosphate groups

Question 5

FAD

Answer 5

a redox cofactor involved in several important reactions in metabolism. FAD can exist in two different redox states, which it converts between by accepting or donating electrons

Question 6

Quinol/ Quinone

Answer 6

Sites in the Q-loop where protons go to cross the membrane

Question 7

FeS Protein

Answer 7

proteins characterized by the presence of iron-sulfur clusters containing sulfide-linked di-, tri-, and tetrairon centers in variable oxidation states.

Question 8

Heme (cytochrome)

Answer 8

membrane-bound hemeproteins containing heme groups and are primarily responsible for the generation of ATP via electron transport.

Question 9

Q-loop

Answer 9

Proton pump in complex III due to the Q-loop. Protons cross the membrane

Question 10

Chemiosmosis

Answer 10

the movement of ions across a selectively permeable membrane, down their electrochemical gradient. Used to make ATP

Question 11

Oxidative Phosphorylation

Answer 11

the metabolic pathway in which the mitochondria in cells use their structure, enzymes, and energy released by the oxidation of nutrients to reform ATP

Question 12

Mitchell Hypothesis

Answer 12

CHEMIOSMOTIC HYPOTHESIS in 1961. The theory suggests that most ATP synthesis in respiring cells comes from the electrochemical gradient across the inner membranes of mitochondria by using the energy of NADH and FADH2 formed from the breaking down of energy-rich molecules, such as glucose.

Question 13

ATP Synthase

Answer 13

The proton gradient is used to make ATP

Question 14

Substrate-level phosphorylation

Answer 14

a type of metabolic reaction that results in the formation of adenosine triphosphate (ATP) or guanosine triphosphate (GTP) by the direct transfer and donation of a phosphoryl (PO3) group to adenosine diphosphate (ADP) or guanosine diphosphate (GDP) from a phosphorylated reactive intermediate.

Question 15

Cytochrome C Oxidase

Answer 15

a large transmembrane protein complex found in bacteria and the mitochondrion. Complex IV

Question 16

Photosynthetic Antenna Pigments

Answer 16

a pigment that is present in chloroplasts or photosynthetic bacteria and captures the light energy necessary for photosynthesis.

Question 17

Photosynthetic Reaction Center

Answer 17

a complex of several proteins, pigments and other co-factors assembled together to execute the primary energy conversion reactions of photosynthesis

Question 18

Oxygenic (non-cyclic) Photosynthesis

Answer 18

Electrons pass from PSII to PSI to make ATP. Electrons passing from PSI make reducing power (NADPH) and electron “holes” in PSII are filled by electrons from H2O and H2S

Question 19

Non-Oxygenic (cyclic) Photosynthesis

Answer 19

Electrons produce PMF, PMF produces ATP, PMF is also used in reverse to create NaDH. This means an electron donor must be used

Question 20

Chlorophyll/ Bacteriachlorophyll

Answer 20

Purple bacteria is only used here. photosynthetic pigments that occur in various phototrophic bacteria

Question 21

PSI/ PSII

Answer 21

functional and structural units of protein complexes involved in photosynthesis that together carry out the primary photochemistry of photosynthesis: the absorption of light and the transfer of energy and electrons

Question 22

Purple Sulfur Bacteria

Answer 22

a group of Proteobacteria capable of photosynthesis, collectively referred to as purple bacteria. They are anaerobic or microaerophilic, and are often found in hot springs or stagnant water

Question 23

Reverse Electron Transport

Answer 23

Where PMF is used to create NADH

Question 24

Green Sulfur Bacteria

Answer 24

a family of obligately anaerobic photoautotrophic bacteria.