Chapter 13 Exam II Master Set

the form of released heat

50% of energy created in the cycle of cellular metabolism is lost. This is in.......

Kinase

A class of enzymes that transfers phosphate ions from one molecule to another. Example: Phosphoglycerate Kinase found in step 7 of glycolysis

Adipocytes

A fat cell that stores triglycerides. They form large droplets in water

Oxaloacetate

A four-carbon molecule that binds with the two-carbon acetyl unit of acetyl-CoA to form citric acid in the first step of the citric acid cycle.

Triacylglycerol

A lipid consisting of three fatty acids linked to one glycerol molecule; also called a fat or triglyceride.

Glycolysis

A metabolic process that breaks down carbohydrates and sugars through a series of reactions to either pyruvic acid or lactic acid and release energy for the body in the form of ATP

occurs via substrate level phosphorylation

ATP is produced in the 7th & 10th steps of glycolysis. This.........

NADH just carries e- to assist enzymes. The main job of NADH is to donate e-s to the ETC, which is essential for the production of ATP.

Although ATP and NADH are both important activated carrier molecules, ATP hydrolysis provides the direct molecular energy for most biochemical reactions. Why do the mitochondria also need to generate high levels of NADH?

A. The ATP must be transported across the inner mitochondrial membrane via a set ADP/ATP antiporters spitting out ATP & bringing in ADP After which it freely diffuses into the cytosol through the permeable outer membrane.

Although the outer mitochondrial membrane is permeable to small molecules, the inner mitochondrial membrane is impermeable in the absence of specific transport proteins. Consider this and what you know about the CTC to answer these questions. A. The ATP generated by oxidative respiration is used throughout the cell. The majority of ATP production occurs in the mitochondrial matrix. How do you think ATP is made accessible to enzymes in the cytosol and other organelles?

ATP synthesis would shut down If all made permeable like the outer membrane, the inflow of all those extra molecules would dissipate the H+ gradient. That gradient is needed to power ATP synthesis thru chemiosmotic coupling. Acetyl CoA would continue to be oxidized by the CTC, thus e-s are still donated to the ECT, but these processes couldn't assist the production of ATP.

Although the outer mitochondrial membrane is permeable to small molecules, the inner mitochondrial membrane is impermeable in the absence of specific transport proteins. Consider this and what you know about the CTC to answer these questions. B. If the inner mitochondrial membrane were rendered as permeable as the outer membrane, how would that affect oxidative phosphorylation? Which specific processes would stop and which remain?

1st: Keeping these rxns separate stops the intermediates of the individual rxns from comingling with other biological pathways that may be occurring near by. It gives the cell control over its rxns. 2nd: Keeping them in their own separate space allows enzymes to be kept in the same space. This benefits the rates and efficiencies in which products can be produced

Although the outer mitochondrial membrane is permeable to small molecules, the inner mitochondrial membrane is impermeable in the absence of specific transport proteins. Consider this and what you know about the CTC to answer these questions. C. Present two types of benefits derived from separating the reactions of glycolysis in the cytosol from those that occur during the citric acid cycle in the mitochondrion.

converted into acetyl CoA.

Amino acids can be transported into the mitochondria and then...........

Isomerase

An enzyme catalyzes the rearrangement of bonds within a single molecule (forming an isomer)

Mutase

An enzyme catalyzes the relocation a functional group within a molecule

Dehydrogenase

An enzyme that catalyzes a chemical reaction during which one or more hydrogen atoms are removed from a molecule.

Kinase

An enzyme that catalyzes the transfer of a phosphate group from ATP to a specified molecule.

Ran-GEF

An exchange factor that catalyzes the exchange of a GDP for a GTP on the Ran protein in the nucleus. GEF Guanine nucleotide exchange factor

an important distinction

Anaerobic respiration is not the same as fermentation. Only fermentation requires an electron-transport chain. This is.......

A: NADH is oxidized to NAD+. B: Under anaerobic conditions, it is the only means of regenerating the NAD+ required for glycolysis, the main energy-generating pathway of an anaerobically growing yeast cell.

Anaerobically growing yeast further metabolizes the pyruvate produced by glycolysis to CO2 and ethanol as part of a series of fermentation reactions. A. What other important reaction occurs during this fermentation step? B. Why is this reaction (that is, the answer to part A) essential for the anaerobically growing cell?

In oxidative phosphorylation, O2 is required to produce ATP, by means of chemiosmotic coupling of process. In substrate-level phosphorylation, the energy released by the enzyme-catalyzed oxidation of a substrate generates ATP directly.

Answer question A: A. How does the generation of ATP by oxidative phosphorylation differ from ATP generation by substrate-level phosphorylation? B. What catabolic process uses substrate-level phosphorylation, and how many ATP molecules are generated in this way in the reaction pathway? C. Where does oxidative phosphorylation take place, and what other processes are required for this to occur?

Glycolysis uses substrate-level phosphorylation and generates 2 ATP for every 1 glucose molecule oxidized to pyruvate molecules

Answer question B: A. How does the generation of ATP by oxidative phosphorylation differ from ATP generation by substrate-level phosphorylation? B. What catabolic process uses substrate-level phosphorylation, and how many ATP molecules are generated in this way in the reaction pathway? C. Where does oxidative phosphorylation take place, and what other processes are required for this to occur?

Oxidative phosphorylation takes place in mitochondria as part of a multistage oxidation process. CTC → ETC → ATP Synthase and the action of the latter two process proton pumps lead to oxidative phosphorylation

Answer question C: A. How does the generation of ATP by oxidative phosphorylation differ from ATP generation by substrate-level phosphorylation? B. What catabolic process uses substrate-level phosphorylation, and how many ATP molecules are generated in this way in the reaction pathway? C. Where does oxidative phosphorylation take place, and what other processes are required for this to occur?

into successively lower energy states.

As the electrons pass through the series of electron acceptor and donor molecules that form the ETC, they fall...........

adding the sugar chain in glycosylation

Asparagine-X-Threonine or Asparagine-X-Serine (x being a variable) is the particular amino acid sequence preferred for........

food molecules, which serve as fuel for cells.

Cells require energy to generate and maintain the biological order that keeps them alive. This energy comes from the chemical bond energy stored in........

food molecules, which serve as fuel for cells.

Cells require energy to generate and maintain the biological order that keeps them alive. This energy comes from the chemical bond energy stored in..........

Citric Acid Cycle

Completes the breakdown of glucose by oxidizing a derivative of pyruvate to carbon dioxide.

energetically unfavorable formation of a high-energy phosphate bond

Coupling of the reactions in step 6 and 7 of glycolysis allows the............

More ATP is produced from fat catabolism than from glucose catabolism. Most ATP is generated in the mitochondria, and the amount depends on the production of the NADH and FADH2 cofactors in the CTC. The CTC relies on the input of acetyl CoA. Each glucose molecule can be converted into two acetyl CoA molecules. A molecule of fat will have 3 fatty acid chains, with an average length of 12-16 carbons. Even if we assume very short fatty acid chains of six carbons each (the length of a glucose molecule), this would mean the production of 3 acetyl CoA molecules per chain, and nine total for the triacylglycerol. In short, because fatty acids have more carbon to their structure, they will produce more Acetyl CoA. So this ultimately will produce more ATP

Do you expect the cell to produce more ATP from 1 glucose molecule or from 1 fatty acid molecule? Explain your answer.

produce 1 Acetyl CoA, 1 NADH, and 1 FADH2

Each one "turn" of the reaction cycle of the beta oxidation of fatty acids, will..........

process of oxidative phosphorylation.

FADH2, like NADH, is a carrier of hydrogens and high-energy electrons. The energy stored in the high-energy e⁻ of NADH and FADH2 is subsequently used to produce ATP through the.............

specialized fat cells called adipocytes

Fats are insoluble in water and form large lipid droplets in the..........

(b) For 2 reasons It Has 10 C: The total number of C atoms determines how many acetyl CoA molecules can be derived from it All of its C-C bonds are saturated: This means that FADH2 will be generated in the 1st step of the fatty acid cycle, converting a C-C → C=C If that bond was unsaturated the cycle begins at the 2nd step. As a result, FADH2 is not generated in that cycle, lowering the total number of cofactors that can be used by the ETC to generate a H+ gradient. Ultimately decreasing the energy yield.

Fatty acids can easily be used to generate energy for the cell. Which of the following fatty acids in the picture will yield more energy? Explain your answer.

Oxidative phosphorylation is a process that occurs in the inner membrane of mitochondria. It requires an ETC that operates on the high-energy electrons taken from the activated carrier molecules NADH and FADH2 that are produced by glycolysis and the CTC. These e-s are transferred through a series of molecules, and the energy released during these transfers is used to generate a gradient of protons, or H+. Because their concentration is much higher outside than inside the mitochondria, the flow of protons, or H+, down the concentration gradient is energetically very favorable and can thus be coupled to the production of ATP from ADP. Thus, oxidative phosphorylation refers to the oxidation of NADH and FADH2 molecules and the phosphorylation of ADP. W/O this process, the yield of ATP from each glucose molecule would be severely decreased.

Fill in the blanks with the best word or phrase selected from the word bank. Oxidative phosphorylation is a process that occurs in the ______ of mitochondria. It requires an ETC that operates on the high-energy electrons taken from the activated carrier molecules ______ & ______ that are produced by glycolysis and the CTC. These e-s are transferred thru a series of molecules, and the energy released during these transfers is used to generate a gradient of ______, or ______. Because their concentration is much ______ outside than inside the mitochondria, the flow of ______, or ______, down the concentration gradient is energetically very ______ and can thus be coupled to the production of ATP from ADP. Thus, oxidative phosphorylation refers to the oxidation of ______ & ______ molecules and the phosphorylation of ______. W/O this process, the yield of ATP from each glucose molecule would be ______ decreased.

FAD

Flavin adenine dinucleotide used to donate electrons for the electron transport chain

preferred energy source of the body

Foods are broken down into simple molecular subunits for distribution and use throughout the body. Simple sugars are the.......

the phosphorylation of ADP to ATP.

From NADH donating its electrons in ETC, a transmembrane gradient of H+ ions is generated and serves as a source of energy for..........

base guanine for adenine.

GTP and GDP are close relatives of ATP and ADP, respectively, the only difference being the substitution of the..........

representing 1 pyruvate. 6 C atoms, so 2 pyruvate.

Glucose is a 6 C molecule. In glycolysis, the splitting or lysis of the glucose creates 2 pyruvate molecules. Think of the 3 C atoms as........

(c) NAD+ As in NAD+ is reduced to NADH

Glyceraldehyde 3-phosphate dehydrogenase operates by stripping a hydride ion from its substrate. Which molecule is the recipient of the proton and two electrons during this transfer? (a) oxygen (b) acetyl CoA (c) NAD+ (d) FADH

they are converted into amino acids, nucleotides, lipids, and other small organic molecules.

Glycolysis & citric acid cycle make the precursors needed to synthesize many important biological molecules. Many of the intermediates of both cycles are used for biosynthetic (anabolic) pathways, where..........

ATP marks the end of glycolysis

Glycolysis Step 10: ADP is transferred to the high energy enol p-linkage (substrate level phosphorylation) and forms ATP. This second production of..........

plasma membrane, trapping it in the cell

Glycolysis Step 1: Glucose is phosphorylated by ATP. This creates a sugar phosphate. The (-) on phosphate prevents passage of the sugar phosphate thru the......

arranged into a 5 membered ring

Glycolysis Step 2: a phosphoglucose isomerization of the sugar phosphate (from step 1) occurs. The 6 membered sugar ring is reversibly isomerized into a chain known as a ketose. Then...........

proceeding steps

Glycolysis Step 3: The ne -OH groups of the 5 membered ring is phosphorylated by ATP. This is in preparation for the formation of 2 sugar phosphates in the.........

will be used in the following step

Glycolysis Step 4: The 6 C (total) sugar is cleaved to produce two 3C sugar phosphates. One of which.........

sugar chain will be oxidized in the next step

Glycolysis Step 5: One sugar from step for is isomerized to form glyceraldehyde 3-phosphate. This.........

a new phosphate linkage are produced, and 1,3-bisphosphoglycerate

Glycolysis Step 6: glyceraldehyde 3-phosphates are oxidized by glyceraldehyde 3-phosphate dehydrogenase. This begins the energy generation of phase of glycolysis. NADH,........

the first ATP is production. And producing 3-phosphoglycerate

Glycolysis Step 7: ADP is transferred to the high energy phosphate linkage on 1,3-bisphosphoglycerate (step 6) via phosphoglycerate kinase. Resulting in........

relatively low free energy of hydrolysis

Glycolysis Step 8: The remaining p-linkage of 3-phosphoglycerate (step 7) are moved to the adjacent C atom due to its..............

the molecule

Glycolysis Step 9: Water is removed from the molecule. As a result, a new high energy enol p-linkage is created on..........

In the CTC occurs more rapidly after the addition of any of its intermediates. This means that if one intermediate is added, levels of all of them increase. In glycolysis, the intermediates downstream of the intermediate being added will be affected. glycolysis: intermediates represented as letters 1A→1B→1C→1D If we add more B 1A→2B→2C→2D Just affecting the intermediates succeeding the intermediate we increased

Glycolysis and the citric acid cycle comprise two different sets of oxidation rxns. The rxn sequence for glycolysis is linear, whereas the rxn sequence for the CTC forms a circle. How does this difference in the arrangement of rxns influence the rate of these processes when an excess amount of a single intermediate is added?

(c) 2 ATP, 2 NADH

Glycolysis generates more stored energy than it expends. What is the net number of activated carrier molecules produced in this process (number and type of molecules produced minus the number of those molecules used as input)? (a) 6 ATP, 2 NADH (b) 4 ATP, 4 NADH (c) 2 ATP, 2 NADH (d) 4 ATP, 2 NADH

Oxygen is not required

Glycolysis is an anaerobic process used to catabolize glucose. What does it mean for this process to be anaerobic?

into carbon dioxide and ethanol

Glycolysis is an anaerobic process; although it will use O2. In the absence of O2, its pyruvates products undergo fermentation. Pyruvate is converted.........

ATP during the conversion.

Glycolysis is one of the main processes involved in cellular respiration. Glycolysis is the pathway that converts sugar into energy, or glucose into pyruvate, generating.........

will feed into the citric acid cycle

Glycolysis produces pyruvate. This pyruvate; and fatty acids from other sources, will convert to acetyl CoA, which.......

is splitting sugars

Glycolysis starts in the cytosol of the cell. As the name implies "glyco + lysis", the process..........

Pyruvate Dehydrogenase Complex

Group of 3 enzymes that convert pyruvate into acetyl CoA. In addition they produce CO2 & NADH. The complex operates in the mitochondrial matrix.

the food we eat (particularly from glucose)

In a big picture, cellular respiration is the way we derive energy from........

muscle cells produces lactate. In a yeast cell, it produces CO2 and ethanol

In absence of O2 NADH can't move into citric acid cycle, so fermentation of pyruvates from glycolysis will occur. The fermentation of pyruvate in........

(c) lactate only for skeletal muscles through fermentation. The ethanol and CO2 are produced by anaerobically growing yeast

In anaerobic conditions, skeletal muscle produces _____________. (a) lactate and CO2. (b) ethanol and CO2. (c) lactate only. (d) ethanol only.

would see clathrin + adaptin 2

In endocytosis, you can see different adaptins. For example along the pathway you'd see in the golgi apparatus clathrin + adaptin 1. Then moving to the next stop in the pathway, the plasma membrane, you........

are directed for acetyl CoA production.

In eukaryotes, the citric acid cycle takes place in mitochondria, in which pyruvate and fatty acids..........

from sugars and fats

In eukaryotic cells, acetyl CoA is produced in the mitochondria from molecules derived........

drive the next step forward

In glycolysis, the energy produced in a step is used to..........

energy overall than complete oxidation.

In muscle cells, pyruvate from glycolysis is converted to lactate in the absence of O2. The rxn restores the NAD+ consumed in glycolysis, but the whole pathway yields much less.........

by way of substrate-level phosphorylation

In the 10th step of glycolysis the second ATP is produced........

negative charge of the phosphate

In the 1st step of glycolysis, a sugar phosphate is produced. This sugar is trapped in the plasma membrane of the cell. This is due to the.......

rearranged into a 5 membered ring

In the 2nd step of glycolysis, sugar phosphate undergoes phosphoglucose isomerization into ketose. In other words, the ring molecule is rearranged into a chain, then again............

two 3C sugar phosphates.

In the 4th step of glycolysis, sugar is cleaved to produce.........

glyceraldehyde 3-phosphate

In the 5th step of glycolysis, 1 sugar isomerized to form.........

NADH and new phosphate linkages (energy)

In the 6th step of glycolysis, glyceraldehyde 3-phosphates are oxidized. Two produce......

3-phosphoglycerate is produced

In the 7th step of glycolysis, 1,3-bisphosphoglycerate receives ADP from the enzyme phosphoglycerate kinase. This produces ATP, thus a P is lost and..........

its carboxyl end. This process converts the acids to acetyl CoA

In the beta oxidation of fatty acids, they are converted to fatty acyl CoA. This is broken down by a cycle of reactions that trims 2 carbons at a time from........

carrier molecules like ATP and NADH

In the cell, enzymes catalyze oxidations of sugars via a series of small steps in which free energy (ΔG) is transferred to...........

molecules like ATP and NADH

In the cell, enzymes catalyze oxidations of sugars via a series of small steps in which free energy is transferred to carrier..........

from its oxidation rxns is carried by NADH and FADH2 to make ATP

In the citric acid cycle w/ O2 present, pyruvate is converted to acetyl CoA & CO2. The cycle converts its acetyl group to CO2 and H2O. The energy released (as e-)......

from H2O

In the electron-transport chain in chloroplasts, low-energy electrons are taken........

(a) The ratio of ATP to ADP in the cytoplasm would fall. If the inner mitochondrial membrane became permeable to H+, the ETC would continue to oxidize NADH to NAD+, transport e-, and pump H+, so the consumption of oxygen would not fall. However, without the energy stored in a proton gradient, there is no way of driving the synthesis of ATP. So ATP synthesis would eventually stop, decreasing the ratio of ATP to ADP in the cytoplasm

In the final stage of the oxidation of food molecules, a H+ gradient is formed across the inner mitochondrial membrane, which is normally impermeable to H+. If cells were exposed to an agent that causes the membrane to become freely permeable to protons, which of the following effects would you expect to observe? (a) The ratio of ATP to ADP in the cytoplasm would fall. (b) NADH would build up. (c) Carbon dioxide production would cease. (d) The consumption of oxygen would fall.

By keeping 3 enzyme activities in a large complex, the substrates are already bound and properly positioned for rapid enzyme catalysis, and the free energy released by one reaction can be readily harnessed for the next. Essentially keeping all three in one complex keeps the molecules all set up and ready for the next enzyme. In addition it allows energy produced in one rxn to drive the next

In the rxn cycle involved in the oxidation of pyruvate, what are the advantages of having 3 enzyme activities contained in a single large complex instead of having 3 smaller and physically independent enzymes?

to allow glycolysis to continue, energy is still required

In yeast w/ anaerobic conditions of glycolysis, pyruvate is converted to ethanol & CO2. This pathway will regenerate NAD+ from NADH. This is needed........

to allow glycolysis to continue

In yeast w/ anaerobic conditions of glycolysis, pyruvate is converted to ethanol and CO2. This pathway will regenerate NAD+ from NADH. This is needed........

A & D are true statements B is false: Heat is may be released from a rxn, but it not stored as energy for biological systems C is false: The description given is actually for anabolism, catabolism is the the breaking down of large molecules into smaller ones

Indicate whether the following statements are true or false. If a statement is false, explain why it is false. A. CO2 and H2O are generated during the oxidation of food molecules. B. Activated carrier molecules store heat energy for the cell to use later. C. Catabolism is a general term that refers to the processes by which large molecules are synthesized from smaller molecules. D. The oxidation of sugar is an energetically favorable process

A. False: The final products of glycolysis are 2 pyruvate. Pyruvate will later be broken down CO2 and H2O in CTC B. False: When fructose 1,6-bisphosphate is cleaved, the products are dihydroxyacetone phosphate & glyceraldehyde 3-phosphate. C. True

Indicate whether the following statements are true or false. If a statement is false, explain why it is false: A. During glycolysis, glucose molecules are broken down to yield CO2 and H2O. B. The cleavage of fructose 1,6-bisphosphate yields two molecules of glyceraldehyde 3-phosphate. C. Anaerobic respiration is not the same as fermentation, in that only fermentation requires an electron-transport chain.

D. False: Under anaerobic conditions, mammalian cells convert pyruvate to lactate in a fermentation process. E. True F. True

Indicate whether the following statements are true or false. If a statement is false, explain why it is false: D. When subjected to anaerobic conditions, glycolysis in mammalian cells continues and causes a buildup of pyruvate in the cytosol. E. The pyruvate dehydrogenase complex catalyzes three different, but linked, enzymatic reactions. F. Amino acids can be transported into the mitochondria and converted into acetyl CoA.

Catabolism

Metabolic pathways that break down molecules, releasing energy.

Guanosine Triphosphate & Guanosine Diphosphate

Molecules similar to ATP & ADP but containing the base guanine instead of adenine

its ATP is generated here as well.

Most of the eukaryotic cell's oxidation rxns occur in mitochondria, and most of............

produce ATP through a process called oxidative phosphorylation

Much of the energy released in the many oxidation rxns of the citric acid cycle is stored as high-energy e- in NADH & FADH2. They carry these electrons to.........

the activated carriers NADH and FADH2

Much of the energy released in the many oxidation rxns of the citric acid cycle is stored as high-energy electrons in..........

(d) excretion of more nitrogenous (ammonia-derived) wastes than with a more balanced diet Because ammonia is given off when amino acids are metabolized to yield energy, but not when sugars & fats are metabolized, you would expect more nitrogenous waste to be excreted.

On a diet consisting of nothing but protein, which of the following is the most likely outcome? (a) loss of weight because amino acids cannot be used for the synthesis of fat (b) muscle gain because the amino acids will go directly into building muscle (c) tiredness because amino acids cannot be used to generate energy (d) excretion of more nitrogenous (ammonia-derived) wastes than with a more balanced diet

Pyruvate

Organic compound with a backbone of three carbon atoms. Two molecules form as end products of glycolysis

about 28 ATP molecules

Oxidative phosphorylation will generally produce..........

observed oxidative reactions in the citric acid cycle.

Poisoning muscle preparations with malonate provided clues to the cyclic nature of the..........

Fermentation

Process by which cells release energy in the absence of oxygen during glycolysis

Beta Oxidation Of Fatty Acids

Process occurring in the mitochondria where fatty acid molecules are converted to acetyl CoA. Also producing 1 NADH & 1 FADH2

Cellular Respiration

Process that releases energy by breaking down glucose and other food molecules in the presence of oxygen

what links glycolysis to the CTC. So glycolysis → 2 pyruvate. Then pyruvate → pyruvate dehydrogenase complex → acetyl CoA & CO2. Then acetyl CoA → CTC

Pyruvate is converted to acetyl CoA and CO2 by pyruvate dehydrogenase complex in the mitochondrial matrix. This complex is........

(d) 3; 60

Pyruvate must move from the cytosol into the mitochondria, where it is oxidized to form CO2 and acetyl CoA by the pyruvate dehydrogenase complex. How many different enzymes and what total number of polypeptides, respectively, are required to perform this oxidation process in the mitochondrion? (a) 1; 60 (b) 3; 3 (c) 3; 26 (d) 3; 60

as a result small amounts of NADH & FADH2 are made to feed oxidative phosphorylation. So if one added more intermediate like succinate (E) to combat the situation, then large amounts of pyruvate would be taken in. Thus all intermediates are produced at a larger rate. And in turn O2, NADH & FADH2 are produced in larger quantities. It is very much so a domino effect

Replenishing the supply of any intermediate has a dramatic effect on the rate at which the entire citric acid cycle operates. For example if low amounts of pyruvate was used, a small amount of O2 was produced and........

drastically produces more everything. Decrease one thing, production of everything slows down

Replenishing the supply of any intermediate has a dramatic effect on the rate at which the entire citric acid cycle operates. Increase one thing, and the cycle....

An enzyme that catalyzes the oxidation of a molecule by removing a hydride ion. (Dehydrogen-ase Removing H)

Several different classes of enzymes are needed for the catabolism of carbohydrates. Which of the following descriptions best matches the function of a dehydrogenase? (a) An enzyme that catalyzes the rearrangement of bonds within a single molecule. (b) An enzyme that catalyzes a change in the position of a specific chemical group within a single molecule. (c) An enzyme that catalyzes the oxidation of a molecule by removing a hydride ion. (d) An enzyme that catalyzes the addition of phosphate groups to other molecules.

(a) An enzyme that catalyzes the rearrangement of bonds within a single molecule. (as in forming an isomer)

Several different classes of enzymes are needed for the catabolism of carbohydrates. Which of the following descriptions best matches the function of a isomerase? (a) An enzyme that catalyzes the rearrangement of bonds within a single molecule. (b) An enzyme that catalyzes a change in the position of a specific chemical group within a single molecule. (c) An enzyme that catalyzes the oxidation of a molecule by removing a hydride ion. (d) An enzyme that catalyzes the addition of phosphate groups to other molecules.

(d) An enzyme that catalyzes the addition of phosphate groups to other molecules.

Several different classes of enzymes are needed for the catabolism of carbohydrates. Which of the following descriptions best matches the function of a kinase? (a) An enzyme that catalyzes the rearrangement of bonds within a single molecule. (b) An enzyme that catalyzes a change in the position of a specific chemical group within a single molecule. (c) An enzyme that catalyzes the oxidation of a molecule by removing a hydride ion. (d) An enzyme that catalyzes the addition of phosphate groups to other molecules.

(b) An enzyme that catalyzes a change in the position of a specific chemical group within a single molecule.

Several different classes of enzymes are needed for the catabolism of carbohydrates. Which of the following descriptions best matches the function of a mutase? (a) An enzyme that catalyzes the rearrangement of bonds within a single molecule. (b) An enzyme that catalyzes a change in the position of a specific chemical group within a single molecule. (c) An enzyme that catalyzes the oxidation of a molecule by removing a hydride ion. (d) An enzyme that catalyzes the addition of phosphate groups to other molecules.

intermediates of the citric acid cycle.

Some amino acids are transported from cytosol into mitochondria, where they are also converted into acetyl CoA or one of the other............

production of NADH & a new high energy phosphate linkage

Step 6 of glycolysis is when where the energy generation phase begins due to the..........

(b) The energy derived from substrate oxidation is coupled to the conversion of ADP to ATP.

Steps 7 and 10 of glycolysis result in substrate-level phosphorylation. Which of the following best describes this process? (a) ATP is being hydrolyzed to phosphorylate the substrate. (b) The energy derived from substrate oxidation is coupled to the conversion of ADP to ATP. (c) Two successive phosphates are transferred, first to AMP, then to ADP, finally forming ATP. (d) The substrate is hydrolyzed using ATP as an energy source.

in a series of small steps. This is cellular respiration

Sugars are oxidized to create energy. Every time a sugar bond is broken from the oxidation, energy is released. These oxidations occur......

fats → amino acids & glycerol

The 1st stage of catabolism is the breaking down of foots into smaller subunits for example proteins → amino acids and,...............

occurs outside cells

The 1st stage of cellular metabolism is the breakdown of macromolecules to simple subunits. This mostly...........

input to feed into stage 3

The 2nd stage of catabolism, simple subunits are broken down further to form acetyl CoA which is the required........

acetyl CoA, which occurs in mitochondria.

The 2nd stage of cellular metabolism is the breakdown of simple subunits to acetyl CoA, with small productions of acetyl CoA & NADH. This occurs mainly in the cytosol, except for the final step of conversion of pyruvate to acetyl groups on..........

used as chemical energy for the cell.

The 3rd stage of catabolism, acetyl CoA is oxidized to CO2, coupled to the production of large amounts of ATP, which is...........

occurs entirely in the mitochondria

The 3rd stage of cellular metabolism is the complete acetyl CoA to H2O and CO2 with large productions of acetyl CoA & NADH. This whole process.......

example of substrate level phosphorylation

The ADP transfer to the phosphate linkage on 1,3-bisphosphoglycerate to produce ATP (step 7 glycolysis) is an........

3 NADH, 1 GTP, 1 FADH2, & 2 CO2

The Net Products Of The Citric Acid Cycle:

(d) succinate dehydrogenase

The O2-dependent rxns needed for cellular respiration were originally thought to occur in a linear pathway. By using a competitive inhibitor for one enzyme in the pathway, investigators discovered that these reactions occur in a cycle. Which enzyme was inhibited? (a) aconitase (b) isocitrate dehydrogenase (c) malate dehydrogenase (d)succinate dehydrogenase

(a) malonate

The O2-dependent rxns required for cellular respiration were originally thought to occur in a linear pathway. By using a competitive inhibitor for one enzyme in the pathway, investigators discovered that these reactions occur in a cycle. What compound served as the inhibitor? (a) malonate (b) malate (c) fumarate (d) succinate

(b) succinate

The O2-dependent rxns required for cellular respiration were originally thought to occur in a linear pathway. By using a competitive inhibitor for one enzyme in the pathway, investigators discovered that these reactions occur in a cycle. Which product in the reaction pathway builds up when the inhibitor is added? (a) citrate (b) succinate (c) fumarate (d) malate

(c) The amount of free energy released by glucose oxidation is the same as combustion, but this energy can actually be used

The advantage to the cell of the gradual oxidation of glucose during cellular respiration compared with its combustion to CO2 and H2O in a single step is that ________________. (a) more free energy is released for a given amount of glucose oxidized. (b) no energy is lost as heat. (c) energy can be extracted in usable amounts. (d) more CO2 is produced for a given amount of glucose oxidized

energy can be extracted in usable amounts.

The advantage to the cell's gradual oxidation of glucose in cellular respiration compared to its combustion to CO2 and H2O in a single step is that energy...........

1 FADH2, 2 CO2

The citric acid cycle catalyzes the complete oxidation of the carbon atoms in acetyl CoA. The net products of the citric acid cycle are: 3 NADH, 1 GTP,.............

(a) Amino acids can be converted into acetyl CoA.

The citric acid cycle is a critical sequence of rxns for energy production, which take place in the matrix of the mitochondria. The rxn cycle requires materials from the cytosol to be converted into acetyl CoA, which represents the starting point of a new cycle. Which of the following statements about acetyl CoA is true? (a) Amino acids can be converted into acetyl CoA. (b) Pyruvate is converted into acetyl CoA in the cytosol. (c) Triacylglycerol molecules are transported into the mitochondrial matrix and cleaved by lipases to produce acetyl CoA. (d) Oxaloacetate is converted directly into acetyl CoA to feed the citric acid cycle.

(a) water

The citric acid cycle is a series of oxidation rxns that remove C atoms from substrates in the form of CO2. Where do the O2 atoms in the CO2 molecules come from? (a) water (b) phosphates (c) molecular oxygen (d) acetyl CoA

(d) 4 Cycles. The 2 C atoms from acetyl CoA are carried through the entire 1st rxn cycle. In the 2nd cycle, one of these C atoms is oxidized to CO2. Two more cycles later, the second C of the pair from that same acetyl CoA is oxidized to CO2.

The citric acid cycle is a series of oxidation rxns that removes C atoms from substrates in the form of CO2. Once a molecule of acetyl CoA enters the CTC, how many complete cycles are required for both of the carbon atoms in its acetyl group to be oxidized to CO2? (a) 1 (b) 2 (c) 3 (d) 4

(b) inhibition of ATP synthesis The H+ gradient driven by H+ pumping in chemiosmotic coupling is what drives ATP synthesis in the inner mitochondrial membrane. An influx of H+ in the matrix would increase the H+ concentration. This dissipate the H+ electrochemical gradient. Without this gradient, ATP will not be produced

The concentration of H+ ions inside the mitochondrial matrix is lower than it is in the cytosol or the mitochondrial intermembrane space. What would be the immediate effect of a membrane-permeable compound that carries and releases H+ into the mitochondrial matrix? (a) inhibition of the electron-transport chain (b) inhibition of ATP synthesis (c) increased import of ADP into the matrix (d) inhibition of the citric acid cycle

preserves energy

The controlled oxidation of sugar in the cell..........

to drive the formation of NADH & a high energy p-linkage. These rxns are coupled

The conversion of glyceraldehyde 3-phosphate to 1,3-bisphosphate requires energy; it is energetically unfavorable. The breaking of the C-H bond via oxidation releases enough energy............

(a) It is hydrolyzed to drive the formation of ATP. This is where the first ATP is generated

The conversion of glyceraldehyde 3-phosphate to 1,3-bisphosphoglycerate in step 6 of glycolysis generates a "high energy" phosphoanhydride bond. Which of the following best describes what happens to that bond in step 7? (a) It is hydrolyzed to drive the formation of ATP. (b) It is hydrolyzed to drive the formation of NADH. (c) It is hydrolyzed to generate pyruvate. (d) It is oxidized to CO2.

other molecules (like in CTC)

The electron carriers NADH and FADH2 transfer electrons to the electron-transport chain that they have gained by oxidizing............

produce H2O.

The electrons NADH donates in the ETC are added to O2 molecules which combine with H+ to........

molecule of NADP+, to produce NADPH.

The electrons passed along the chloroplast ETC are ultimately passed on to a.........

the intermembrane space.

The energy released for the ETC is used to drive H+ ions (protons) across the inner mitochondrial membrane to.............

process of oxidative phosphorylation.

The energy stored in the high-energy e⁻ of NADH and FADH2 is subsequently used to produce ATP through the.............

Phosphoglycerate Kinase Enzyme

The enzyme need for ADP transfer to p-groups on 1,3-bisphosphoglycerate to produce the first ATP of glycolysis. This occurs in step 7

Phosphoglycerate Kinase

The enzyme responsible for ADP transfer to p-groups on 1,3-bisphosphoglycerate to produce the first ATP of glycolysis. All of this occurs in step 7

Glyceraldehyde 3-Phosphate Dehydrogenase

The enzyme responsible for the oxidation of glyceraldehyde 3-phosphates in step 6 of glycolysis producing NADH and high energy p-linkages

Glyceraldehyde 3-Phosphate Dehydrogenase Enzyme

The enzyme responsible for the oxidation of glyceraldehyde 3-phosphates in step 6 of glycolysis producing NADH and high energy phosphate linkages

Substrate-Level Phosphorylation

The enzyme-catalyzed formation of ATP by direct transfer of a phosphate group to ADP from an intermediate substrate

(b) pyruvate.

The final metabolite produced by glycolysis is ___________. (a) acetyl CoA. (b) pyruvate. (c) 3-phosphoglycerate. (d) glyceraldehyde 3-phosphate.

Phosphoglucose Isomerization

The isomerization (rearrangement) of the sugar phosphate into a chain structure. This occurs in step 2 of glycolysis to produce a ketose

2 pyruvate, 2 ATP, 2 NADH

The net products of glycolysis are:

A) When malonic acid was added to the minced muscle samples, compound E accumulated and the concentrations of compounds F, G, and H were severely diminished. Krebs interpreted this to mean that malonic acid blocked one of the rxns by inhibiting the enzyme involved. This has became known as the malonate block. B) After the malonate block is in place, if compound A is added in excess, compound E will accumulate, inhibiting the pathway at this point and preventing the conversion of E to F. If the experiment is repeated and compound G is added in excess instead of compound A, the result is the same. The first explanation for this result was that the F → G → H pathway somehow also led to an intermediate that could be converted into compound E. C) When Krebs combined pyruvate and oxaloacetate (compound H) w/ the muscle suspensions, he noticed an immediate production of citrate (compound A). This result made it logical to conclude that H is recycled and used in the 1st rxn. The model of a rxn cycle explained all the other previous results, including the observation that any one compound can be added to increase O2 uptake. A large amount of any intermediate will drive the production of the others, as long as pyruvate is available. The cofactors produced are used in the electron-transport chain, which terminates with the splitting of oxygen and its reduction to form water.

The oxidative rxns of cellular respiration were the focus of intense study in the 1930s. These rxns are represented in a linear pathway, as they were thought to occur. Each product is designated as a lettered compound (A through H) A. What was the first observation that Krebs made when he added malonic acid to the minced muscle samples, and what was his conclusion about how and where it was acting in the reactions he was studying? B. What happens when the malonate block is introduced and subsequently compound A is added in excess? What is the result if compound G is added after the block, instead of A? How did Krebs attempt to reconcile these two results? C. What additional observation led Krebs to hypothesize that what was previously thought to be a linear sequence of reactions is actually a cyclic sequence of reactions? How did this idea further explain the earliest observations that the addition of any single compound in the pathway greatly increases oxygen uptake by the muscle tissue?

three different, but linked, enzymatic reactions.

The pyruvate dehydrogenase complex catalyzes..........

(c) oxaloacetic acid cycle is not another name for the CTC.

The reaction cycle that uses acetyl CoA to generate electron carrier molecules needed in the ETC is important for powering the cell. Which of the names below is not one of those commonly used to describe this reaction cycle? (a) tricarboxylic acid cycle (b) Krebs cycle (c) oxaloacetic acid cycle (d) citric acid cycle

analogous to the mitochondrial matrix

The stroma is the fluid-filled space surrounding the grana. The stroma is..............

are all operating at the same time

The three cycles in cellular respiration are glycolysis, the citric acid cycle and the electron transport chain. In reality, these three things..........

the mitochondria through beta oxidation of fatty acids

Triacylglycerols have their CH tails cleaved creating fatty acids. Fatty acids are converted to acetyl CoA in...........

from ER → golgi and golgi → ER

Understand that COP-coating is the protein coating on a protein present for the vesicular transport........

much smaller energy yield than a complete oxidation

Understand that the anaerobic process of fermentation will restore NAD+ consumed in glycolysis. But the whole pathway has a.........

less energy than a complete oxidation

Understand that the anaerobic process of fermentation will restore NAD+ consumed in glycolysis. But the whole pathway produces a lot.........

An e- carrier that donates high-energy electrons for synthesis of ATP

What is NADH?

converted to lactate.

When inadequate O2 is present, for example, in a muscle cell undergoing vigorous contraction, the pyruvate produced by glycolysis is.........

will occur

When oxygen is absent in glycolysis, fermentation.........

(a) anaerobically growing yeast All the other cells can perform oxidative phosphorylation to generate additional ATP.

Which of the following cells rely exclusively on glycolysis to supply them with ATP? (a) anaerobically growing yeast (b) aerobic bacteria (c) skeletal muscle cells (d) plant cells

(d) glycogen breakdown does not take place in the mitochondria. This occurs in the cytosol

Which of the following processes do not take place in the mitochondria? (a) citric acid cycle (b) conversion of pyruvate to activated acetyl groups (c) oxidation of fatty acids to acetyl CoA (d) glycogen breakdown

Choice (d) is the correct answer. Oxidative phosphorylation produces about 28 ATP molecules

Which of the following stages in the breakdown of the piece of toast you had for breakfast generates the most ATP? (a) the digestion of starch to glucose (b) glycolysis (c) the citric acid cycle (d) oxidative phosphorylation

D is false The chloroplast will uses CO2 to fuel C fixation to make sugars. The mitochondria can use the sugars for the CTC which makes CO2 It also produces O2 in photosynthesis which the mitochondria can use for oxidative phosphorylation. But at no point can the mitochondria use CO2 produced by the chloroplast

Which of the following statements is NOT correct? a. Carbon dioxide given off by mitochondria may be used by chloroplasts. b. Oxygen released by chloroplasts may be used by mitochondria. c. Heat is released by reactions occurring in the chloroplast and mitochondria. d. Carbon dioxide given off by chloroplasts may be used by mitochondria.

(c) Conversion of pyruvate to acetyl CoA. One carbon is oxidized and released as carbon dioxide when pyruvate is converted to acetyl CoA.

Which of the following steps or processes in aerobic respiration include the production of carbon dioxide? (a) breakdown of glycogen (b) glycolysis (c) conversion of pyruvate to acetyl CoA (d) oxidative phosphorylation

A: glycolysis, E: glycogen break down, and F: release of fatty acids from triacylglycerols all occur in the cytosol

Which of the listed process occurs at 1 (the cytosol)

G: oxidative phosphorylation occurs in the inner mitochondrial membrane

Which of the listed process occurs at 2 (the inner mitochondrial membrane)

B: the citric acid cycle, C: conversion of pyruvate → acetyl CoA, and D: oxidation of fatty acids → acetyl CoA all occur in the mitochondrial matrix

Which of the listed process occurs at 3 (the mitochondrial matrix)