CH 6 Mastering Biology

Why is the citric acid cycle called a cycle?

Acetyl CoA binds to oxaloacetate and this compound is restored at the end of the cycle

The final electron acceptor of cellular respiration is ___.

Oxygen

Cellular respiration requires fuel (glucose) and oxygen gas. The main process that produces these inputs is___.

Photosynthesis

In glycolysis, ATP molecules are produced by ___?

Substrate level phosphorylation

In glycolysis, what starts the process of glucose breakdown?

ATP

What enters the citric acid cycle?

Acetyl CoA

For each glucose that enters glycolysis, ___ NADH enter the electron transport chain

10

How many NADH are produces by glycolysis?

2

In glycolysis there is a net gain of ___ ATP.

2

What is/ are the most important output(s) of glycolysis?

2 pyruvic acid and 2 NADH molecules

A molecule that functions as the electron donor in a redox reaction ___ A. Loses electrons and becomes oxidized B. Loses electrons and becomes reduced C. Gains electrons and becomes reduced D. Gains electrons and becomes oxidized

A

In the first stage of cellular respiration (glycolysis), two molecules of pyruvate are produced. In the remaking stages of cellular respiration, a number of additional products, such as ___. These other stages occur in the ___. A. ATP... mitochondria B. Glucose... mitochondria C. Water... cytoplasm D. ATP... cytoplasm

A

Oxidative phosphorylation could not occur without glycolysis and the citric cid cycle, because ___/ A. These two stages supply the electrons needed for the electron transport chain B. These two stages provide the water that is split during oxidative phosphorylation C. These two stages provide the oxygen used as the final electron acceptor D. The electron transport chain requires the ATP produced during the first two stages

A

Primarily, cellular respiration serves to... A. Make ATP to power the cells activities B. Break down toxic molecules C. Produce cell structures from chemical building blocks D. Make food

A

When a car engine burns gasoline, the results of the reaction are similar to when cells burn glucose. Both reactions release carbon dioxide and water. In cells, the chemical energy in foods is converted to ATP and heat. In a moving car, the chemical energy in gasoline is converted to... A. Kinetic energy and heat B. Thermal energy and heat C. Potential energy and heat D. ATP and heat

A

Where do the reactions of the citric acid cycle occur in eukaryotic cells? A. The mitochondrion B. The cytoplasmic fluid C. The folds of the inner mitochondrial membrane D. The inter membrane space of mitochondrion

A

In preparing pyruvate to enter the citric acid cycle, which of the following steps occurs?

A compound called coenzyme A binds to a two carbon fragment.

In cellular respiration, glucose __ electrons, whereas ___ electrons. A. Gains... oxygen loses B. Loses... oxygen gains C. Gains... water loses D. Loses... water gains

B

___ is to a mitochondrion as ___ is to a chloroplasts. A. ATP... CO2 B. O2... CO2 C. Sunlight... ATP D. Glucose... O2

B

As shown below, an electron carrier, such as ___, acts as an energy storage molecule when it is___ A. NAD+... oxidized B. NAD+... reduced C. NADH... reduced D. NADH... oxidized

C

Sunlight is essential for the varied life on earth. Sunlight provides energy to photosynthetic organisms by providing... A. The energy required to drive cellular respiration B. Heat to leaves, which is converted to useful energy for work C. The energy necessary to power the rearrangement of chemical bonds in H2O and CO2 D. Heat to leaves, which is used to synthesize chloroplasts

C

What is not a product of glycolysis?

FADH2

Each turn of the citric acid cycle generates one ATP and ___ additional energy rich molecules: ___.

Four; 3 NADH and 1 FADH2

Glycolysis is the multi step breakdown of ___. Several different ___ play a role in this process.

Glucose... enzymes

A chemist has discovered a drug that blocks an enzyme that catalyze the second reaction in glycolysis. He wants to use the drug to treat people with bacterial infections. However he cant do this because ___.

Human cells also perform glycolysis; the drug might also poison them

Unlike the citric acid cycle and electron transport, glycolysis occurs___.

In the cytoplasm

Muscle cells, fermentation produces ___.

Lactate and NAD+

In cellular respiration, most ATP molecules are produced by ___

Oxidative phosphorylation

Most NADH molecules generated during cellular respiration are produced during___?

The citric acid cycle

Which part(s) of cellular respiration require(s) oxygen gas.

The citric acid cycle and the electron transport chain