Kapitel 14

Question 1

Part of a photosystem that captures light energy and channels it into the photochemical reaction center. It consists of protein complexes that bind large numbers of chlorophyll molecules and other pigments.

Answer 1

antenna complex

Question 2

Transmembrane enzyme complex in the inner membrane of mitochondria and the thylakoid membrane of chloroplasts. Catalyzes the formation of ATP from ADP and inorganic phosphate during oxidative phosphorylation and photosynthesis - respectively. Also present in the plasma membrane of bacteria.

Answer 2

ATP synthase (F1Fo ATPase)

Question 3

Process by which inorganic carbon (as atmospheric CO2) is incorporated into organic molecules. The second stage of photosynthesis. (Figure 14–40)

Answer 3

carbon-fixation reaction

Question 4

In photosynthesis - the light-induced transfer of a high-energy electron from chlorophyll to an acceptor molecule resulting in the formation of a positive charge on the chlorophyll and a negative charge on a mobile electron carrier.

Answer 4

charge separation

Question 5

Mechanism in which an electrochemical proton gradient across a membrane (composed of a pH gradient plus a membrane potential) is used to drive an energy-requiring process - such as ATP production or the rotation of bacterial flagella.

Answer 5

chemiosmotic coupling (chemiosmosis)

Question 6

Light-absorbing green pigment that plays a central part in photosynthesis in bacteria - plants - and algae.

Answer 6

chlorophyll

Question 7

A specialized invagination of the inner mitochondrial membrane.

Answer 7

crista (plural cristae)

Question 8

Colored heme-containing protein that transfers electrons during respiration and photosynthesis.

Answer 8

cytochrome

Question 9

Third of the three electron-driven proton pumps in the respiratory chain. It accepts electrons from cytochrome c and generates water using molecular oxygen as an electron acceptor. (Figure 14–18)

Answer 9

cytochrome c oxidase complex

Question 10

Second of the three electron-driven proton pumps in the respiratory chain. Accepts electrons from ubiquinone and passes them to cytochrome c. (Figure 14–18)

Answer 10

cytochrome c reductase

Question 11

Electron-transporting group consisting of either two or four iron atoms bound to an equal number of sulfur atoms - found in a class of electron-transport proteins. (Figure 14–16)

Answer 11

iron–sulfur cluster

Question 12

Uniparental inheritance observed - for example - in the inheritance of mitochondria in animals and plants - where mitochondrial DNA is inherited only through the maternal line.

Answer 12

maternal inheritance

Question 13

Large internal compartment of the mitochondrion. The corresponding compartment in a chloroplast is known as the stroma.

Answer 13

mitochondrial matrix

Question 14

First of the three electron-driven proton pumps in the mitochondrial respiratory chain - also known as Complex I. It accepts electrons from NADH and passes them to a quinone. (Figure 14–18)

Answer 14

NADH dehydrogenase complex

Question 15

Process in bacteria and mitochondria in which ATP formation is driven by the transfer of electrons through the electron-transport chain to molecular oxygen. Involves the intermediate generation of an electrochemical proton gradient across a membrane and a chemiosmotic coupling of that gradient to the ATP synthase. (Figure 14–10)

Answer 15

oxidative phosphorylation

Question 16

The part of a photosystem that converts light energy into chemical energy in photosynthesis. (Figure 14–44)

Answer 16

photochemical reaction center

Question 17

Light-driven reactions in photosynthesis in which electrons move along an electron-transport chain in a membrane - generating ATP and NADPH.

Answer 17

photosynthetic electron-transfer reactions

Question 18

Multiprotein complex involved in photosynthesis that captures the energy of sunlight and converts it to useful forms of energy: a reaction center plus an antenna (Figure 14–45)

Answer 18

photosystem

Question 19

The force exerted by the electrochemical proton gradient that moves protons across a membrane.

Answer 19

proton-motive force

Question 20

Small - lipid-soluble - mobile electron carrier molecule found in the respiratory and photosynthetic electron-transport chains. (Figure 14–17)

Answer 20

quinone (Q)

Question 21

Pair of molecules in which one acts as an electron donor and one as an electron acceptor in an oxidation–reduction reaction: for example - NADH (electron donor) and NAD+ (electron acceptor). (Panel 14–1 - p. 765)

Answer 21

redox pair

Question 22

The affinity of a redox pair for electrons - generally measured as the voltage difference between an equimolar mixture of the pair and a standard reference. NADH/NAD+ has a low redox potential and O2/H2 has a high redox potential (high affinity for electrons). (Panel 14–1 - p. 765)

Answer 22

redox potential

Question 23

Reaction in which one component becomes oxidized and the other reduced; an oxidation–reduction reaction. (Panel 14–1 - p. 765)

Answer 23

redox reaction

Question 24

Electron-transport chain present in the inner mitochondrial membrane that generates an electrochemical gradient across the membrane that is used to drive ATP synthesis. (Figures 14–4 and 14–10)

Answer 24

respiratory chain (electron-transport chain)