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