Metabolism: 5.2, 9.1-9.6, 10

O2

O2

Each electron travels with a proton, and the protons are not transferred directly to ________, but instead are usually passed first to an electron carrier, a coenzyme that can cycle easily between its oxidized form (NAD+) and its reduced form (NADH)

Cellular respiration

________ does not oxidize glucose in a single explosive step rather its broken down in a series of steps, each one catalyzed by an enzyme.

redox reactions

Not all ________ involve the complete transfer of electrons from one substance to another.

molecular oxygen

At the end of the chain, the electrons are combined with ________ and hydrogen ions, forming water.

Photosynthesis

________ generates oxygen, as well as organic molecules used by the mitochondria of eukaryotes as fuel for cellular respiration.

Fermentation

________ is a partial degradation sugars or other organic fuel that occurs without the use of oxygen.

Metabolic

________ pathways that release stored energy by breaking down complex molecules are called catabolic pathways.

eukaryotic cells

In ________, the inner membrane of the mitochondrion is the site of electron transport and chemiosmosis (to make up oxidative phosphorylation)

ATP

The energy released at each step of the chain is stored in a form the mitochondria can use to make ________ from ADP- (oxidative phosphorylation)

Aerobic respiration

________ is the most efficient catabolic pathway in which oxygen is consumed as a reactant along with the organic fuel.

complex molecules

Through the activity of enzymes, a cell systematically degrades ________ that are rich in potential energy to simple waste products that have less energy.

electron donor

The ________ is called the reducing agent.

Energy

________ must be added to pull an electron away from an atom.

addition of electrons

The ________ to another substance is known as reduction.

smaller amount of ATP

Produces a(n) ________ directly in a few reactions of glycolysis and the Krebs cycle.

citric acid cycle

The ________ (Krebs cycle) completes the breakdown of glucose to carbon dioxide by oxidizing acetyl CoA.

Redox reactions

________ are the transfer of one or more electrons.

Energy

________ flows into an ecosystem as sunlight and exits as heat; in contrast, the chemical elements essential to life are recycled.