Masteringbiology Homework Glycolysis and Krebs Cycle

Which statement describes the citric acid cycle?

This process produces some ATP and carbon dioxide in the mitochondrion.

Which statement describes glycolysis?

This process splits glucose in half and produces 2 ATPs for each glucose.

Which statement describes the electron transport chain?

This process uses energy captured from electrons flowing to oxygen to produce most of the ATPs in cellular respiration.

As shown below, an electron carrier, such as____, acts as an energy-storage molecule when it is_____

FADH2....Oxidized

The major (but not sole) energy accomplishment of the citric acid cycle is the _____.

Formation of NADH and FADH2

Cellular respiration completely breaks down a glucose molecule through glycolysis and the citric acid cycle. However, these two processes yield only a few ATPs. The majority of the energy the cell derives from glucose is _____.

Found in NADH and FADH2

Which of the following molecules is broken down in cellular respiration, providing fuel for the cell?

Glucose

Of the metabolic pathways listed below, the only pathway found in almost all organisms is _____.

Glycolysis

What is the name of the process in which glucose is converted to pyruvate?

Glycolysis

We inhale O2 and we exhale CO2. Carbon dioxide is produced _____.

In the reaction that creates acetyl CoA (coenzyme A) from pyruvate

What happens to the energy that is given up by electrons as they move through the electron transport chain?

It pumps H+ through a membrane.

A molecule is oxidized when it____

Loses an electron

A molecule that functions as the electron donor in a redox reaction_____

Loses electrons and loses energy

In cellular respiration, glucose___electrons, while ____electrons

Loses...Oxygen Gains

Glycolysis is the only stage of cellular respiration that _____.

Requires ATP to make ATP

In glycolysis, ATP molecules are produced by _____.

Substrate-level phosphorylation

Most of the NADH that delivers high-energy electrons to the electron transport chain comes from _____.

The citric acid cycle

The ATP synthase in a human cell gets energy for making ATP directly from _____.

The flow of H+ through a membrane

Where do the reactions of the citric acid cycle occur in eukaryotic cells?

The mitochindrion

The enzyme ATP synthase catalyzes the phosphorylation of ADP to form ATP. In eukaryotic cells, the energy needed for this endergonic reaction is derived from _____.

The movement of hydrogen ions across the mitochondrial membrane

Oxidative phosphorylation could not occur without glycolysis and the citric acid cycle, because _____.

These two stages supply the electrons needed for the electron transport chain

In a eukaryotic cell, the electron transport chain is precisely located in or on the _____.

Cristae of the mitochondrion

How many NADH are produced by glycolysis?

2

In glycolysis there is a net gain of _____ ATP.

2

During glycolysis, a molecule of glucose is partially oxidized. What is the net gain of ATP and NADH for each molecule?

2 ATP and 2 NADH

The energy production per glucose molecule through the citric acid cycle is _____.

2 ATP, 6 NADH, 2 FADH2

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.

What is the mechanism of action for the enzyme ATP synthase? ATP is formed _____.

Due to the potential energy of a concentration gradient of hydrogen ions across a membrane

In glycolysis, what starts the process of glucose breakdown?

ATP

Which energy-rich molecule produced by cellular respiration directly powers cell work?

ATP

Why is the citric acid cycle called a cycle?

Acetyl CoA binds to oxaloacetate that is restored at the end of the cycle.

A small amount of ATP is made in glycolysis _____.

By the transfer of a phosphate group from a fragment of glucose to ADP (substrate-level phosphorylation)

A small amount of ATP is made in glycolysis _____.

By the transfer of a phosphate group from a fragment of the glucose to ADP (Substrate-level phosphorylation)

What is the correct general equation for cellular respiration?

C6H12O6 + 6 O2 → 6 CO2 + 6 H2O + ATP energy

In the first stage of cellular respiration, two molecules of pyruvate are produced. In the remaining stages, a number of products are produced, including _____. This process occurs in the _____.

CO2 ... mitochondria

The function of cellular respiration is to_____

Extract usable energy from glucose

Which of the following serves primarily as a hydrogen-atom carrier molecule in cells?

FAD

Which of these is NOT a product of glycolysis?

FADH2

Which of the following processes takes place in the cytosol of a eukaryotic cell?

Glycolysis

Select the correct sequence of steps as energy is extracted from glucose during cellular respiration.

Glycolysis → acetyl CoA → citric acid cycle → electron transport chain

Where does glycolysis occur in a eukaryotic cell?

In the cytoplasmic fluid

Primarily, cellular respiration serves to______

Make ATP to power the cell's activities

Dinitrophenol (DNP) is a highly toxic, membrane uncoupler. What happens when DNP makes the phospholipid bilayer of inner mitochondrial membranes permeable to protons (H+)?

Many protons would bypass ATP synthase, leading to a sharp decline in ATP synthesis.

The electron transport chain is a series of electron carrier molecules. In eukaryotes, where can this structure be found?

Mitochondria

A scientist wants to study the enzymes of the citric acid cycle in eukaryotic cells. What part of the cell would they use as a source of these enzymes?

Mitochondrial matrix

In what organelle would you find acetyl CoA formation, the citric acid cycle, and the electron transport chain?

Mitochondrion

Once the citric acid cycle has been completed, most of the usable energy from the original glucose molecule is in the form of _____.

NADH

In oxidative phosphorylation, electrons are passed from one electron carrier to another. The energy released is used to _____.

Pump protons (H+) across the mitochondrial membrane

In eukaryotes, most of the high-energy electrons released from glucose by cell respiration _____.

Reduce NAD+ to NADH, which then deliver them to the electron transport chain