chapter 6
When Lactic acid builds up in the muscles it causes ________ in the muscles. After ____ hour of being in the muscles the lactic acid leaves the muscle and enters the ________ and goes to the _______.
fatigue ... one ... blood stream ... liver
What starts the Krebs cycle?
Acetyl (NO CoA!!!!)
Pyruvate is broken down into __________
Acetyl CoA
Why is the citric acid cycle called a cycle? NADH is recycled in the electron transport chain. Glucose is cycled around and resynthesized. NAD+ and FAD are recycled. Acetyl CoA binds to oxaloacetate and this compound is restored at the end of the cycle
Acetyl CoA binds to oxaloacetate and this compound is restored at the end of the cycle
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.
Which type of cell can glycolysis occur in?
All cells
The chemical ingredients needed for photosynthesis are _____ and _____
CO2 and Water
In an experiment, mice were fed glucose (C6H12O6) containing a small amount of radioactive oxygen. The mice were closely monitored, and in a few minutes, water NADH carbon dioxide ATP
Carbon dioxide
A scientist wants to study the enzymes of the citric acid cycle in eukaryotic cells. What part of the cell would she use as a source of these enzymes?
Mitochondrial matrix
How is your breathing related to cellular respiration?
O2 is needed for the most efficient form of cellular respiration to take place
How many times does glycolysis occur per glucose?
Once
_________ binds to _______ to create ________ at the very beginning of the Krebs cycle.
Oxaloacetate ... Acetyl ... citrate
What is the role of oxygen in cellular respiration?
Oxygen takes the high energy electrons after they go through the ETC
The poison cyanide binds to an electron carrier within the electron transport chain and blocks the movement of electrons. When this happens, glycolysis and the citric acid cycle soon grind to a halt as well. Why do you think these other two stages of cellular respiration stop?
They runout of NAD+ and FAD
What is the purpose of the Krebs cycle?
To fill up the electron carriers and bring them to the ETC (PPPPPAAARRRRTTTTAAAAYYYYYY)
What is the purpose of the grooming stage?
To prepare the food (pyruvate) to enter the mitochondrial matrix and proceed to the Krebs cycle
What happens in the energy investment phase?
Two ATP are added to Glucose and it forms 2 G3P (Glyceraldehyde tri-phosphate)
Why are sweating and other body-cooling mechanisms necessary during vigorous exercise?
When you are exercising, the rate of cellular respiration is increased because of the increase in need for ATP. Cellular respiration is an exergonic reaction so some of the energy is going to be released as heat energy so, to stop your body from overheating, body-cooling mechanisms start to work to cool down your body
What organism can do alcoholic fermentation?
Yeast
Besides sugars and fats, organisms can use other molecules as fuel for cellular respiration. When protein molecules are used, _____ are produced as waste.
amino groups
what is an intermediate in cells
an intermediate is a complex that appears during the course of a reaction but does not appear in the net reaction, or as a final product
Glycolysis is an _________and ________ process
ancient ... anaerobic
In muscle cells, fermentation produces _____.
lactate and NAD+
Sports physiologists at an Olympic training center want to monitor athletes to determine at what point their muscles begin to function anaerobically. They could do this by checking for a buildup of _____.
lactic acid
Recent data suggests that heat-generating brown fat is most active in __________ people.
lean people exposed to cold temperatures
A molecule is oxidized when it _____.
loses an electron
What is produced in the energy payoff phase?
pyruvate (pyruvic acid)
Glycolysis produced a net gain total of 2 ____________, 2__________, and 2________.
pyruvate ... NADH+H+ ... ATP
In which of the following is the first molecule becoming reduced to the second molecule? pyruvate → acetyl CoA pyruvate → lactate glucose → pyruvate NADH + H+ → NAD+ + 2 H
pyruvate → lactate
What is the first phase of glycolysis?
the energy investment phase
What is the purpose of glycolysis?
to break down glucose (food)
How many NADH are produced by glycolysis?
2
How many NADH+H+ are produced in The grooming stage?
2
How many NADH+H+ are produced in glycolysis?
2
How many times does the Krebs cycle occur per glucose?
2
In glycolysis there is a net gain of _____ ATP.
2
At the end of the grooming stage ___ CO2, ___ NADH+H+, and ___ Acetyl CoA are produced.
2 ... 2 ... 2
How many ATP are used in Glycolysis? How many are gained total? What is the net gain?
2 ... 4 ... 2
The amount of ATP, NADH, and FADH2 production per glucose molecule through the citric acid cycle is _____.
2 ATP, 6 NADH, 2 FADH2
NADH is also used by cells when making certain molecules. Based on your knowledge of NADH's role in cellular respiration, what do you think NADH's role is in biosynthesis of molecules?
Reducing them
What is the second phase of glycolysis?
The energy payoff phase
What is misleading about the following statement? "plant cells perform photosynthesis, and animal cells perform cellular respiration."
The sentence implies that cellular respiration does not occur in plant cells when it does.
What is the ultimate fate of the electrons that are stripped from glucose during cellular respiration?
They are used to form water
When does the grooming stage occur?
after glycolysis and before the Krebs cycle
What chemical characteristic of the element of oxygen accounts for the function in cellular respiration?
It's electronegetivity
Bacteria have no membrane-enclosed organelles. However, some still generate ATP through cellular respiration. Where is the electron transport chain found in these organisms?
Plasma Membrane
What happens in the grooming stage?
Pyruvate loses CO2, is oxidized by NAD+. These to processes create acetyl. A Coenzyme is added to acetyl creating Acetyl CoA
What happens in the energy pay off phase?
The 2G3P's lose two electrons and two hydrogens in a redox reaction. The G3P gets oxidized. Then, substrate level phosphorylation occurs adding a P to the substance. substrate level phosphorylation occurs again taking a P away from the substance and adding it to ADP to create ATP. The substance now has one phosphate left. Water is then removed and substrate level phosphorylation occurs again removing the last phosphate, adding it onto ADP to make ATP and creating pyruvate (pyruvic acid)
Describe what happens in the Krebs cycle. (one turn, not two)
The Acetyl enters the Mitochondrial matrix after leaving its CoA at the membrane. The 2 carbon ACETYL attaches to the 4 carbon OXALOACETATE and creates a 6 carbon CITRATE. Citrate then gets oxidized by NAD+ and a CO2 molecule is also removed. This creates a 5 carbon ALPHA-KETOGLUTARATE and one NADH+H. (the NAD+ got reduced to NADH+H+) The ALPHA-KETOGLUTARATE gets oxidized by NAD+ and another CO2 molecule is removed. Substrate level phosphorylation occurs and one ATP is made. A 4 carbon SUCCINATE is then made. SUCCINATE is oxidized by FAD creating FADH2 (FAD is REDUCED to FADH2. FADH2 is the product of reduction.) No carbons are removed! When SUCCINATE is oxidized, it creates FUMARATE. Water is added to FUMARATE creating MALATE. MALATE is then oxidized by NAD+ creating OXALOACETATE which then binds to another ACETYL and the process continuing.
Of the three main stages of cellular respiration, which is the only one that uses oxygen?
The Oxidative phosphorylation and technically the citric acid/ Krebs cycle.
Explain how proteins go through cellular respiration.
The amino group breaks off and depending on what the amino group is attached to it will either go to glycolysis, grooming, or Krebs
What is the meaning of glycolysis?
The breakdown of glucose
Where does oxidative phosphorylation take place?
The inner mitochondrial membrane
What is the purpose of embedding the electron transport chain in the membrane of a cell?
The membrane is impermeable to H+.
Where does the Krebs/citric acid cycle take place?
The mitochondrial matrix
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
How do Fats get broken down into energy?
They are broken down into Glycerol and Fatty acids. The fatty acids go strait to the grooming stage and broken down into acetyl CoA and the rest of cellular respiration occurs. The Glycerol is broken down into G3P and from there continues in glycolysis.
Fat is the most efficient molecule for long-term energy storage, even compared to carbohydrates, because _____.
They have more hydrogen atoms so they have more high energy electrons
What does cyanide and carbon monoxide do?
They prevent O2 from entering the mitochondria. O2 is not present to get reduced and there is a decrease in H+ content build up.
Which of the following is a true distinction between cellular respiration and fermentation? 1) NADH is oxidized by passing electrons to the electron transport chain in respiration only. 2) Only respiration oxidizes glucose. 3) Substrate-level phosphorylation is unique to fermentation; cellular respiration uses oxidative phosphorylation. 4) Fermentation is the metabolic pathway found in prokaryotes; cellular respiration is unique to eukaryotes.
1) NADH is oxidized by passing electrons to the electron transport chain in respiration only.
For each glucose that enters glycolysis, _____ NADH enter the electron transport chain.
10
How many ADP are produced in glycolysis?
2
How many ATP are produced The Krebs cycle?
2
How many ATP are produced in Glycolysis? (net gain)
2
How many ATP are produced in the citric acid cycle?
2
How many CO2 are produced The grooming stage?
2
How many CoA's are attached in The grooming stage?
2
How many FADH2 are produced The Krebs cycle?
2
How many H2O are produced in glycolysis?
2
The electron transport chain is, in essence, a series of redox reactions that conclude cellular respiration. During these redox reactions, _____. 1) NADH is reduced as it donates electrons to the first complex involved in the electron transport chain 2) NADH is oxidized, which then reduces an electron acceptor in the electron transport chain 3) all the carriers pump H+ across the mitochondrial membrane, forming a gradient that is used to drive ATP synthesis 4) ATP synthase removes hydrogen ions and pumps them across the mitochondrial membrane
2) NADH is oxidized, which then reduces an electron acceptor in the electron transport chain
Which of the following statements regarding the movement of electrons during cellular respiration is true? 1) O2 is eventually oxidized by the electrons to form water. 2) O2 is reduced when it accepts electrons and forms water. 3) The electrons release large amounts of energy each time they are transferred from one molecule to another. 4) Electrons tend to move away from O2.
2) O2 is reduced when it accepts electrons and forms water.
How many carbons are there for each substance and what are the names of the substances? IN ORDER!!!!!
2...Acetyl, 6...Citrate, 5...Alpha-ketoglutarate, 4...succinate, 4...fumarate, 4...malate, 4...oxaloacetate
What part of cellular respiration generates the most ATP?
Chemiosmosis/Oxidative phosphorylation
Within the nucleus of a cell, long DNA molecules and associated proteins form fibers called _____.
Chromatin
In the grooming stage, the ___________ acts as a ticket to enter the ___________ and continue the process of cellular respiration in the ___________ cycle.
CoA ... Mitochondrial matrix ... Krebs/citric acid
An important enzyme involved in the regulation of redox reactions is____________.
Dehydrogenase
NADH drops off their electrons at the __________ protein complex and FADH2 drops them off at the___________ protein complex.
First ... seccond
Explain what happens in alcoholic fermentation.
Glucose is broken down through glycolysis during alcoholic fermentation. The, CO2 is released and the pyruvate accepts the two electrons from the NADH+H+ creating 2 2carbon molecules called ethanol.
What is the formula for Lactic acid fermentation?
Glucose —> 2 ATP + 2 LACTATE
What is the formula for alcoholic fermentation?
Glucose—>Ethanol+CO2
What is the oldest process to generate ATP?
Glycolysis
Explain what happens in lactic acid fermentation.
Glycolysis occurs and then the pyruvate accept the electrons from the NADH+H and it created lactate
What are the stages of cellular respiration in order?
Glycolysis, Grooming stage, Krebs or citric acid cycle, oxidative phosphorylation
During fermentation, __________ that was produced during glycolysis is converted back to __________.
NADH ... NAD+
During electron transport, energy from _____ is used to pump hydrogen ions into the _____.
NADH and FADH2 ... intermembrane space
Describe what happens in the ETC.
NADH and FADH2 drop off their electrons at the first and second protein complex and then they move through the carriers and protein complexes. Each time an electron leaves and enters a protein complex it pumps H+ through the protein complex. the electrons finally go to the O to reduce it and create water. This created a higher proton gradient in the inter mitochondrial membrane. These protons push down on the ATP synthase and cause it to allow a proton to enter. This causes the ATP synthase to rotate and ATP to be made
Does the CoA enter the mitochondria?
No, it is left behind so that the food can enter the mitochondrial matrix
_________ is the final electron acceptor. in other words it is the last to be reduced.
O2
Most NADH molecules generated during cellular respiration are produced during __________.
The Citric acid cycle
Cellular respiration accomplishes two major processes: (1) it breaks glucose down into smaller molecules, and (2) it harvests the chemical energy released and stores it in ATP molecules. By the end of _____, the breakdown of glucose is complete; most ATP molecules are produced during _____.
The Citric acid cycle ... ETC
Where does glycolysis take place?
The Cytoplasm
Where does the grooming stage take place?
The Cytoplasm
facultative anaerobe
can do both anaerobic and aerobic respiration
The proximate (immediate) source of energy for oxidative phosphorylation is _____.
kinetic energy that is released as hydrogen ions diffuse down their concentration gradient
Where does glycolysis occur in a eukaryotic cell?
in the cytoplasmic fluid
Where is the ETC in eukaryotes?
innermitochondrial membrane
Cells can take _________ and uses energy to make them into ________, ___________, and _________.
intermediates ... carbs ... proteins ... fats
What does Oligomycin do?
it blocks the ATP synthase channel. this causes the enzymes not to turn and no ATP is made.
What does DNP do?
it makes the mitochondrial phospholipid bilayer permeable to H+. This causes the H+ to even out and there is no pressure on ATP synthase and so is cannot create any ATP.
Is ATP synthase part of the ETC?
no
How many ATP are used in the energy payoff phase? How many are gained total? What is the net gain?
no energy is used in the payoff phase, four ATP are gained total and the net gain is 4.
strict anaerobe (obligate anaerobe)
only anaerobic. O2 kills them
In cellular respiration, most ATP molecules are produced by _____.
oxidative phosphorylation
Some human cells, such as nerve cells, are restricted to aerobic respiration to recycle NADH and FADH2. If these cells are deprived of oxygen, then _____.
oxidative phosphorylation would come to a halt because there wouldn't be any oxygen to "pull" the electrons down the transport chain
Protein complex 5 is the last complex to be ________.
oxidized
The final electron acceptor of cellular respiration is _____.
oxygen
Bacteria have no membrane-enclosed organelles. However, some still generate ATP through cellular respiration. Where is the electron transport chain found in these organisms?
plasma membrane
Where is the ETC in prokaryotes?
plasma membrane
In the citric acid cycle (also called the Krebs cycle), ATP molecules are produced by _____.
substrate level phosphorolation
In glycolysis, ATP molecules are produced by _____.
substrate-level phosphorylation
The fold of the mitochondria are important because they create a higher __________ so more _______ can be made because theres more ___________ and ___________.
surface area ... ATP ... ETC ... ATP synthase
What is the genetic center of the eukaryotic cell?
the nucleus
A kilocalorie is defined as...
the quantity of heat needed to raise the temperature of 1 kg of water by 1°C.
How many times does the grooming stage occur per glucose?
twice
An important end product of cellular respiration is _____.
water
Through respiration, humans breathe in O2 and breathe out CO2. However, what would happen if we did not breathe in O2?
we would not make enough ATP to meet our energy requirements
Fat is the most efficient molecule for long-term energy storage even compared to carbohydrates because _____.
with their numerous hydrogen atoms, fats provide an abundant source of high-energy electrons
How many ADP are produced The Krebs cycle?
0
Which of these enters the citric acid cycle (also called the Krebs cycle)? 1) G3P 2) pyruvate 3) acetyl 4) NADH + H+ 5) glucose
3) acetyl CoA
How many ADP are produced The grooming stage?
0
How many ATP are produced in The grooming stage?
0
How many CO2's are produced in glycolysis?
0
How many CoA's are attached in glycolysis?
0
How many FAD are produced The Krebs cycle?
0
How many FAD are produced The grooming stage?
0
How many FAD are produced in glycolysis?
0
How many FADH2 are produced The grooming stage?
0
How many FADH2 are produced in glycolysis?
0
How many H2O are produced The Krebs cycle?
0
How many H2O are produced The grooming stage?
0
How many NAD+ are produced The Krebs cycle?
0
How many NAD+ are produced The grooming stage?
0
How many NAD+ are produced in glycolysis?
0
During glycolysis, a molecule of glucose is partially oxidized. What is the net gain of ATP and NADH for each glucose molecule during this chemical pathway?
2 ATP and 2 NADH
How many ATP are used in the energy investment phase? How many are gained total? What is the net gain?
2 ATP are used, none are gained at all.
In preparing pyruvate to enter the citric acid cycle, which of the following steps occurs? 1) Carbon dioxide must be present for pyruvate to enter the citric acid cycle. 2) A compound called coenzyme A binds to a two-carbon fragment. 3) Oxygen atoms are formed into oxygen gas. 4) Pyruvate is reduced by oxidizing an NAD+ to an NADH.
2) A compound called coenzyme A binds to a two-carbon fragment.
In preparing pyruvate to enter the citric acid cycle, which of the following steps occurs? In preparing pyruvate to enter the citric acid cycle, which of the following steps occurs? 1) Oxygen atoms are formed into oxygen gas. 2) A compound called coenzyme A binds to a two-carbon fragment. 3) Carbon dioxide must be present for pyruvate to enter the citric acid cycle. 4) Pyruvate is reduced by oxidizing an NAD+ to an NADH.
2) A compound called coenzyme A binds to a two-carbon fragment.
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 food is converted to ATP and heat. In a moving car, the chemical energy in gasoline is converted to _____. 1) potential energy and heat 2) thermal energy and heat 3) kinetic energy and heat 4) ATP and heat
3) kinetic energy and heat
How many Co2 are produced The Krebs cycle?
4
From Glycolysis to the Krebs cycle, how many ATP, NADH+H+, and FADH2 are made? (net gain)
4 ATP, 10 NADH+H+, 2 FADH2
Which of these is NOT a product of glycolysis? 1) water 2) NADH + H+ 3) pyruvate 4) ATP 5) FADH2
5) FADH2
How many NADH+H+ are produced The Krebs cycle?
6
In glycolysis, what starts the process of glucose breakdown?
ATP
In the first stage of cellular respiration (glycolysis), two molecules of pyruvate are produced. In the remaining stages of cellular respiration, a number of additional products are produced, such as __________. These other stages occur in the __________.
ATP ... Mitochondria
We inhale O2 and we exhale CO2. Carbon dioxide is produced in the reaction that creates _________ from pyruvate.
In a reaction that created CoA from pyruvate
The Mitochondrial Matrix is more _________ and the inter membrane is more __________.
basic ... acidic
What does rotenone do?
blocks protein complex 1. NADH+H+ cant drop off electrons and only 4 ATP are made because FADH2 can still pass but 4 ATP is not enough for a cell to survive off of.
