Cellular Respiration #2
How many FADH2 molecules are produced by 1 turn of the Krebs Cycle?
1
How many FADH2 are produced per turn of the Krebs cycle? How many FADH2 are produced per glucose during the Krebs cycle?
1 FADH2 is produced per turn of the Krebs cycle. 2 FADH2 are produced during the Krebs cycle per molecule of glucose.
During the bridge reaction, how many NADH are produced per pyruvate? How many NADH are produced per molecule of glucose?
1 NADH is produced per molecule of pyruvate. 2 NADH are produces per molecule of glucose.
How many FADH2 molecules are produced by 1 molecule of glucose?
2
The number of ATP molecules produced out of Krebs Cycle is:
2
The Krebs cycle begins when the acetyl-CoA binds the 2-carbon ____ to the 4-carbon _____ to produce the 6-carbon _____.
2-carbon acetate 4-carbon oxaloacetic acid 6-carbon citric acid
How many NADH are produced per turn of the Krebs cycle? How many NADH are produced per glucose during the Krebs cycle?
3 NADH are produced per turn of the Krebs cycle. 6 NADH are produced during the Krebs cycle per molecule of glucose.
How many CO2 molecules are produced by the Krebs Cycle for a molecule of glucose?
4
What molecule produced during the bridge reaction enters the Krebs cycle?
Acetate (Acetyl Co-A)
Prior to entering the Krebs Cycle, each pyruvate molecule loses electrons, hydrogen ions, and a carbon, forming an energy-rich molecule of
Acetyl-CoA
In the reactions just prior to the Krebs cycle, pyruvate is converted into what compound?
Acetyl-CoA or acetate
Krebs Cycle is part of_______________ respiration.
Aerobic
To convert 3-carbon pyruvate to 2-carbon acetate requires the removal of what compound?
Carbon dioxide
What happens to the CoA?
CoA attaches the acetate to oxaloacetic acid. It is then regenerated to be used again.
Folds in the mitochondrion are called:
Cristae
What happens to pyruvic acid at the end of glycolysis? (There are two possibilities. Give both.)
If oxygen is present, the pyruvic acid will enter the mitochondria for aerobic respiration. If oxygen is absent, pyruvate remains in the cytoplasm and enters fermentation.
What is the disadvantage of glycolysis?
If the cell only carries out glycolysis, it would quickly run out of NAD+ to accept the hydrogen electrons. Without NAD+, the cell cannot keep glycolysis going.
What two aerobic stages of respiration occur in the mitochondria?
Krebs Cycle Electron Transport Chain
Krebs Cycle takes place in the:
Matrix
The inner most interior of the mitochondrion is called the:
Matrix
The Krebs cycle is the "machinery" of respiration that churns out molecules/atoms of what four types?
NADH FADH2 ATP CO2 (as a waste product)
After the Krebs Cycle only a small portion of the energy of glucose has been converted to ATP. At this point the majority of usable energy is contained in
NADH and FADH2
Which of the following passes the high-energy hydrogen electrons to the electron transport chain?
NADH and FADH2
What is one thing that is NOT related to The Kreb's Cycle?
NADPH
How many ATP are produced per turn of the Krebs cycle? How many ATP are produced per molecule of glucose during the Krebs cycle?
One ATP is produced per acetate. Two ATP are produced per glucose during the Krebs cycle.
The molecule that is "regenerated" during the Krebs Cycle is:
Oxaloacetate
Before entering the Krebs Cycle, pyruvate is:
Oxidized into Acetyl-CoA
What molecule from glycolysis enters the mitochondria for aerobic respiration?
Pyruvic acid
Where does aerobic respiration take place in prokaryotic organisms?
Since prokaryotic organisms do not contain mitochondria, the electron transport chain occurs along the cell membrane.
What happens to the ATP produced during respiration?
The ATP is used for all cellular activities requiring energy.
The Kreb's Cycle is also known as:
The Citric Acid Cycle
The inner membrane of the mitochondria has many folds and loops. What are these folds and loops called and what is their function?
The folds and loops are called cristae. They increase the surface area for the reactions of the electron transport chain.
As molecules are oxidized during the Krebs cycle, what will happen to the H+ ions?
The hydrogen acceptors NAD+ and FAD will attach to the hydrogen ions and transport these high-energy electrons to the electron transport chain.
What are two advantages of glycolysis?
The process is so fast that thousands of ATP are produced in just a few milliseconds. Since glycolysis does not require any oxygen, energy for the cell can be produced even when no oxygen is available.
What name is given to the space inside the inner membrane? What is the function of this area?
The space is called the matrix. It contains the enzymes that are needed for the reactions of the Krebs cycle as well as mitochondrial DNA and ribosomes.
Why is the conversion of pyruvate to acetate called the "bridge reaction"?
This reaction occurs as the pyruvate is entering the mitochondria. So this reaction is the "bridge" between: The cytoplasm and the mitochondria Anaerobic and aerobic respiration Glycolysis and the Krebs cycle.
During glycolysis, how many NADH are produced?
Two NADH are produced per glucose
As molecules are oxidized during the Krebs cycle, how many molecules of CO2 are produced? What will happen to them?
Two molecules of CO2 are produced per turn of the Krebs cycle. This means 2 molecules of CO2 per acetate, or 4 molecules of CO2 per molecule of glucose. The cell gives off the CO2 as a waste product.
What is the final end product of glycolysis? How many of this molecule have been produced?
Two molecules of pyruvic acid (pyruvate) have been produced by the end of glycolysis.
All of the following are fuctions of the Krebs cycle except:
adding electrons and protons to oxygen to form water
Where does the electron transport chain occur?
along the cristae membranes.
NADH and FADH2
carry electrons to the ETC.
After Acetyl-CoA is added to an oxaloacetate molecule, __________ is immediately formed. This is why the Kreb's cycle is sometimes called the citric acid cycle.
citric acid
What is the name of the membrane of which respiration must occur?
cristae
What is the fluid inside the mitochondria that contains the enzymes and co-enzymes required for respiration?
matrix
The enzymes that catalyze the reactions of the Krebs cycle are found in which organelle?
mitochondria
Pyruvic acid formed in glycolysis will be ____ in the presence of oxygen.
oxidized (broken down) in the bridge reactions
Which of the following is not an end product of the Kreb's cycle?
pyruvate
The Krebs cycle reactions begin with the binding of _______ to oxaloacetic acid to form _______.
the 2-carbon Acetyl CoA; a 6-carbon citric acid
Where in the mitochondria does the Krebs cycle occur?
the matrix of the mitochondria.
The CO2 that is produced immediately before the Krebs cycle comes from
the removal of one carbon atom and 2 oxygen atoms from a pyruvate