BIOL 1010-How Cells Obtain Energy Study Guide; Chp.4
Chemiosmosis (4)
1. H+ ions diffuse through inner membrane through ATP synthase. 2. The concentration of H ions creates an electrochemical gradient or potential voltage across the membrane. ·3. This force provides the energy needed for the ATP synthase to catalyze synthesis of ATP from ADP + phosphate (32-34 ATP). 4. Electrons are used to reduce O molecules to O ions which attract H ions and form water.
What does ATP stand for and what is it composed of (3)?
Adenosine triphosphate and is composed of adenine, ribose, and three phosphate.
Metabolism
All of the chemical reactions that take place within the cell.
An enzyme is also referred to as...
Biological catalyst.
Cofactors vs. Coenzymes
Both are "enzyme sidekicks" that can help enzymes with their jobs of building up or breaking down substrates into products. They can either bind to the substrate or the active site. Confactors: Usually metal ions. Conenzymes: Usually organic vitamins.
Where does the Citric Acid Cycle take place?
Mitochondria.
In which of the following do the events of the citric acid cycle occur in eukaryotes?
Mitochondrial matrix.
Aerobic cellular respiration can make ___________ ATP than fermentation.
More.
What types of cells can perform glycolysis?
Most prokaryotes and eukaryotes.
Which electron carriers are involved in oxidative phosphorylation (2)?
NADH and FADH₂
With regard to enzymes, why are vitamins and minerals necessary for good health (5)? Give examples.
Vitamins and minerals are used as coenzymes and cofactors that helps enzymes catalyze reactions. Many enzymes require the binding of certain cofactor's or coenzymes to be able to catalyze their reactions. Since enzymes catalyze many important reactions, it's critical to obtain sufficient vitamins and minerals from diet and supplements. Ex: Vitamin C (absorbic acid) is a coenzyme necessary for the action of enzymes that build collagen. Ex: Heme is a cofactor with an iron atom in the center found in blood which creates the hemoglobin proteins and activates it.
Coenzymes (2)
Vitamins that assist in the normal functioning of enzymes. They are organic helper molecules.
Reduction
When ATP and NADPH use their stored energy to convert the three-carbon compound, 3-PGA, into another three-carbon compound called G3P.
Fixation (2)
When RuBisCO catalyzes a reaction between CO2 and RuBP. This forms a six-ring carbon compound that is immediately converted into two three-ring compounds.
Regeneration
When a G3P molecules leaves the Calvin cycle to contribute to the formation of the carbohydrate molecule, which is commonly glucose.
Electron transport (4)
Where electrons are transferred from NADH and FADH2 to create a proton gradient of H+. This gradient is use to power the enzyme ATP synthase. Oxygen is the last receptor and produces water. Electron transport requires oxygen and takes place in the mitochondria.
Heat energy
The energy transferred from one system to another that is not work.
Why is there no electron transport chain in the fermentation process?
The last step of cellular respiration needs oxygen for electron transport.
Active site
The location within the enzyme where the substrate binds that is usually on the surface of the enzyme.
Would you describe the metabolic pathways as inherently wasteful or inherently economical. Why (3)?
The metabolic pathways are very economical. The substrates, intermediates and products move between the pathways and do so in response to finely tuned feedback inhibition loops that keep metabolism overall on an even keel. Intermediates is one pathway may occur in another and they can move from one pathway to another fluidly in response to the needs of the cell.
We inhale oxygen when we breathe and exhale carbon dioxide. What is the oxygen used for and where does the carbon dioxide come from (3)?
The oxygen we inhale is the final electron receptor in the electron transport chain and allows aerobic respiration to proceed. This is the most efficient pathway for harvesting energy in the form of ATP from food molecules. The carbon dioxide we breathe out is formed during the citric acid cycle when the bonds in the carbon compounds are broken.
Enzymes usually end in ___________ but sugars usually end in ___________.
-ase;-ose.
The citric acid cycle contains how many steps?
8.
Explain the fermentation process (4)
1. NADH cannot be oxidized (lose electrons) for the electron transport chain to become NAD+ 2. NAD+ needs to be regenerated so another process it added. 3. Two types of fermentation could happen: alcoholic or lactic acid. 4a. In alcoholic fermentation (yeast) the 2 pyruvate from glycolysis makes CO2 and 2 ethenol. 4b. In lactic acid fermentation (in muscle cells) when your blood can give more oxygen for demand and the 2 pyruvate makes 2 lactate.
Explain the process of glycolysis (7).
1. Takes place in the cytoplasm and anaerobic. 2. Using energy from 2 ATP molecules, 6 carbon is split into 2 three carbon molecules, called Glyceradlehyde-3-Phosphate. 3. Each of the 3 carbon molecules' bonds are broken so NAD+ picks up electrons and hydrogen ions to become NADH. 4. The energy released is use to attach phosphate groups to both 3 carbon molecules. 5. Phosphate groups are transferred to ADP and are removed. 6. The ADP then becomes ATP and more reactions take place to rearrange the molecules. 7. 2 pyruvate is generated, 2 ATP and 2 NADH.
Explain the process the the Citric Cycle (7).
1. Takes place in the mitochondria and aerobic. 2. The 2 pyruvate from glycolysis is converted into 2 Acetyl CoA through the mitochondrial matrix and 2 CO₂ is released. 3. Electrons from pyruvate are transferred to NADH which becomes NAD+ 4. The 2 carbon Acetyl CoA attaches to the 4 carbon oxaloacetate to form citrate. 5. The 6 carbon molecule (citrate) goes through multiple biochemical changes to a 4 carbon molecule (oxaloacetate) where bonds form and break. 6. NAD+ carries electrons away which form NADH and FADH carries electrons away too. 7. Produces ATP, 2 CO₂, 3 NADH and FADH₂.
Electron transport chain process (4)
1. The electrons from NADH and FADH2 pass through 4 protein complexes and lose their energy. 2. This energy is used to pump H ions from mitochondrial matrix to the intermembrane system. 3. At the 4th protein complex, electrons are accepted by terminal acceptor oxygen. 4. Oxygen (with the extra electrons) bonds with 2 H ions to form water.
Glycolysis has how many steps?
10.
What are the products of the Citric Acid Cycle (3)?
2 ATPs, 3 NADH, FADH2.
What are the products of glycolysis (3)?
2 pyruvate, 2 ATP, 2 NADH.
How many net ATP are produced during lactic acid fermentation?
2.
How many total ATP is produced in glycolysis?
2.
In glycolysis, per glucose ______ ATP is made and _______ NADH is made.
2;2.
How many ATP are produced from the electron transport chain?
32-34 ATP.
List the equation for photosynthesis, it's reactants and products.
6 CO₂ + 6 H₂O --L-I-G-H-T--> C₆H₁₂O6 + 6 O₂ Reactants: 6 carbon dioxide and 6 water. Products: 1 glucose and 6 oxygen.
Citric acid cycle has how many steps?
8.
Citric Acid Cycle/Krebs Cycle (3)
A chemical cycle involving eight steps that completes the metabolic breakdown of glucose molecules begun in glycolysis by oxidizing acetyl CoA (derived from pyruvate) to carbon dioxide; occurs within the mitochondrion in eukaryotic cells and in the cytosol of prokaryotes; together with pyruvate oxidation, the second major stage in cellular respiration.
NADH
A coenzyme and it has the ability to transfer electrons, which will be very useful in making even more ATP later on.
System
A group of interacting, interrelated, or interdependent elements or parts that function together as a whole to accomplish a goal.
Beta oxidation
A reaction that converts fatty acids to acetyl CoA to enter the Krebs cycle.
Entropy
A thermodynamic quantity representing the unavailability of a system's thermal energy for conversion into mechanical work, often interpreted as the degree of disorder or randomness in the system.
The energy currency used by cells is _____. A. ATP B. ADP C. AMP D. adenosine
A. ATP
Which of the following is true of an endergonic reaction? A. Endergonic reactions require an energy input. B. Endergonic and exergonic reactions are the same. C. Endergonic reactions happen before exergonic reactions can begin. D. Endergonic reactions release energy.
A. Endergonic reactions require an energy input.
Which of the following is not an example of an energy transformation? A. Heating up dinner in a microwave B. Solar panels at work C. Formation of static electricity D. None of the above
A. Heating up dinner in a microwave
What happens to the glucose molecule during glycolysis? A. It is converted to two pyruvate molecules. B. It is converted to water. C. It is converted to acetyl CoA. D. It is converted to CO2.
A. It is converted to two pyruvate molecules.
Which of the following is produced during oxidative phosphorylation? A. NADH B. water C. FADH2 D. carbon dioxide
A. NADH
Which of the following is not true about enzymes? A. They are consumed by the reactions they catalyze. B. They are usually made of amino acids. C. They lower the activation energy of chemical reactions. D. Each one is specific to the particular substrate(s) to which it binds.
A. They are consumed by the reactions they catalyze.
Which of the following fermentation methods can occur in animal skeletal muscles? A. lactic acid fermentation B. alcohol fermentation C. mixed acid fermentation D. propionic fermentation
A. lactic acid fermentation
All the chemical reactions that take place inside a human body are collectively referred to as which of the following? A. metabolism B. catabolism C. bioenergetics D. anabolism
A. metabolism
What types of cells can perform glycolysis? A. most prokaryotic and eukaryotic cells B. plants C. animals D. bacteria
A. most prokaryotic and eukaryotic cells.
Which of the following is an example of potential energy? A. sitting on a couch B. doing jumping jacks C. riding a bicycle downhill D. swinging on a rope swing
A. sitting on a couch
Chemical energy is the energy of which of the following? A. the bonds that hold a molecule together B. motion of a sprinter C. heat from a fireplace D. electricity used to run a blender
A. the bonds that hold a molecule together.
What does ATP become when one of its phosphate is broken for energy?
ADP or Adenosine Diphosphate.
________ is produced during the Citric Acid Cycle.
ATP.
The cholesterol synthesized by cells uses which component of the glycolytic pathway as a starting point?
Acetyl CoA.
What are the components of an ATP molecule (3)?
Adenine, ribose, and three phosphate groups.
Non-competitive inhibition
An inhibitor molecule binds to the enzyme in a location other than the active site (allosteric site).
Cofactors (3)
Any nonprotein molecule or ion that is required for the proper functioning of an enzyme. Cofactors can be permanently bound to the active site or may bind loosely with the substrate during catalysis. They are inorganic ions. Ex: iron or magnesium-usually metal ions
Enzyme (2)
Are biological chemical catalysts that speed up chemical reactions by lowering their activation energy and ends in -ase. Ex: Lactase (enzyme) breaks down lactose (substrate/disaccharide) for out body to digest easier
Which of the following is a product of lactic acid fermentation? A. water B. ATP C. alcohol D. yeast
B. ATP.
What do the electrons added to NAD+ do? A. They become part of a fermentation pathway. B. They go to another pathway for ATP production. C. They energize the entry of the acetyl group into the citric acid cycle. D. They are converted into NADP.
B. They go to another pathway for ATP production.
The cholesterol synthesized by cells uses which component of the glycolytic pathway as a starting point? A. glucose B. acetyl CoA C. pyruvate D. carbon dioxide
B. acetyl CoA.
Which of the following is a product of alcoholic fermentation? A. lactate B. carbon dioxide C. water D. oxygen
B. carbon dioxide
Which of the following is a product of alcoholic fermentation? A. oxygen B. carbon dioxide C. lactate D. water
B. carbon dioxide.
The last step of aerobic respiration is referred to as which of the following? A. the citric acid cycle B. oxidative phosphorylation C. the Krebs Cycle D. the Calvin Cycle
B. oxidative phosphorylation
When amino acids are broken down for energy, ammonia is created, which is converted into _____ and excreted in urine. A. uranium B. urea C. phosphatase D. ammonium
B. urea
Chcolesterol can be used as an energy source for the body; where else can it be used? A. within the nucleus to provide protection for the DNA B. within cell membranes to provide flexibility C. within the nucleus to provide protection for the RNA D. within ribosomes to assist in protein production
B. within cell membranes to provide flexibility.
Cholesterol can be used as an energy source for the body; where else can it be used? A. within the nucleus to provide protection for the DNA B. within cell membranes to provide flexibility C. within the nucleus to provide protection for the RNA D. within ribosomes to assist in protein production
B. within cell membranes to provide flexibility.
Catabolic reactions (4)
Break down complex chemicals into simpler ones. It produces energy, polymers are broken down and is degradation.
What enzyme is required to produce ATP during oxidative phosphorylation? A. glucase B. pepsin C. ATP synthase D. acetylcholinesterase
C. ATP synthase
Which of the following is produced during alcoholic fermentation? A. lactate B. water C. CO2 D. FADH2
C. CO2
What do the electrons added to NAD+ do? A. They energize the entry of the acetyl group into the citric acid cycle. B. They become part of a fermentation pathway. C. They go to another pathway for ATP production. D. They are converted into NADP.
C. They go to another pathway for ATP production.
During anaerobic respiration, the final electron acceptor is which of the following? A. oxygen B. glucose C. an inorganic molecule D. water
C. an inorganic molecule
During anaerobic respiration, the final electron acceptor is which of the following? A. water B. oxygen C. an inorganic molecule D. glucose
C. an inorganic molecule.
If a reaction releases free energy it is termed which of the following? A. endergonic reaction B. bioenergetic reaction C. exergonic reaction D. metabolic reaction
C. exergonic reaction.
Energy is stored long-term in the bonds of _____ and used short-term to perform work from a(n) _____ molecule. A. ATP : glucose B. an anabolic molecule : catabolic molecule C. glucose : ATP D. a catabolic molecule : anabolic molecule
C. glucose : ATP
Which of the following fermentation methods can occur in animal skeletal muscles? A. mixed acid fermentation B. propionic fermentation C. lactic acid fermentation D. alcohol fermentation
C. lactic acid fermentation
If a human body has an insufficient supply of oxygen, the skeletal muscle cells may switch from cellular respiration to which of the following? A. metabolism B. photosynthesis C. lactic acid fermentation D. alcoholic fermentation
C. lactic acid fermentation.
Which of the following can be used as an energy source inside a human body? A. water B. carbon dioxide C. proteins D. oxygen
C. proteins.
Beta oxidation is ________. A. the breakdown of sugars B. the assembly of sugars C. the breakdown of fatty acids D. the removal of amino groups from amino acids
C. the breakdown of fatty acids.
Chemiosmosis involves... A. the movement of electrons across the cell membrane B. the movement of hydrogen atoms across a mitochondrial membrane C. the movement of hydrogen ions across a mitochondrial membrane D. the movement of glucose through the cell membrane
C. the movement of hydrogen ions across a mitochondrial membrane
Chemiosmosis involves which of the following? A. the movement of hydroxide ions across the cell membrane B. the movement of electrons and protons across the cell membrane C. the movement of hydrogen ions across the cell membrane D. the movement of electrons across the cell membrane
C. the movement of hydrogen ions across the cell membrane.
Inhibitor
Can modify the enzyme shape.
Closed system
Cannot exchange energy with its surrounding.
Enzymes are _______________ that can be used ___________ with subtrates.
Catalyst;repeatly.
∆G
Change in free energy.
Which two lipids are connected to the glucose pathway?
Cholesterol and triglycerides.
FADH₂
Coenzyme that helps in the electron transfer to make ATP.
Where does glycolysis take place?
Cytoplasm.
Lactic acid is also...
C₃H₆O₃
What is the formula for cellular respiration?
C₆H₁₂O₆ + 6O₂ ---> 6CO₂ + 6H₂0 + ATP energy
Which of the following is true about enzymes? A. They are consumed by the reactions they catalyze. B. They are usually made of lipids. C. They raise the activation energy of chemical reactions. D. Each one is specific to the particular substrate(s) to which it binds.
D. Each one is specific to the particular substrate(s) to which it binds.
During fermentation, what type of molecule is used to regenerate NAD+ from NADH? A. oxygen B. an inorganic molecule C. water D. an organic molecule
D. an organic molecule.
When excess glucose is present in the human body, it gets stored as which of the following? A. proteins B. glucagon C. fatty acids D. glycogen
D. glycogen.
Metabolic pathways are considered what type of system? A. closed B. open and closed C. neither open nor closed D. open
D. open
The glucose that enters the glycolysis pathway is split into two molecules of _________. A. ATP B. phosphate C. NADH D. pyruvate
D. pyruvate
Which of the following is one form of long-term energy store in animals? A. waxes B. cholesterol C. steroids D. triglycerides
D. triglycerides.
Biogenetics
Describe the concept of energy flow.
Anabolic reactions (4)
Describes the pathway that requires a net energy input to synthesize complex molecules from simpler ones. It requires energy, builds polymers and is synthesis.
The NADH and FADH₂ from the Citric Acid cycle are ______________ ____________ which can be used next in the _____________ _____________ __________.
Electron;carriers;electron;transport;chain.
oxidative phosphorylation is the _____________ _______________ ____________ + ______________.
Electron;transport;chain;chemiosmosis.
Open system
Energy can be exchanged with its surroundings (stove top).
Enzymes can be denatured by...(3)
Extreme pH, extreme salt environment and extreme temperature.
In each transfer of an electron through the electron transport chain phase of oxidative phosphorylation, the electron gains energy. T or F
F.
Muscles in the human body convert kinetic energy in food to create chemical energy through movement. T or F
F.
The molecular structure of an enzyme changes only in an exergonic reaction. T or F
F.
Triglycerides store about the same amount of energy as carbohydrates. T or F
F.
What process makes bread dough rise? A. the Calvin cycle B. fermentation C. oxidative phosphorylation D. glycolysis
Fermentation.
Glycolysis (2)
First pathway used in the breakdown of glycose into two three-carbon molecules with the production of ATP and NADH.
Calvin cycle has three stages. What are they?
Fixation, Reduction and Regeneration
NAD+ is reduced to NADH when it ___________ electrons.
Gained.
Photosynthesis makes ______________ but cellular respiration ____________ glucose.
Glucose;breaks.
When excess glucose is present in the human body, it gets stored as which of the following?
Glycogen.
While glucose is an efficient source of short-term energy, _______ is stored in the liver and muscle in case blood sugar levels drop.
Glycogen.
What are the three steps of cellular respiration?
Glycolysis, citric acid cycle, electron transport chain.
For Anaerobes, ATP product stops at the end of which process?
Glycolysis.
To release the energy from an ATP molecule by removing a phosphate bond occurs via what process?
Hydrolysis.
Where does fatty acid breakdown take place?
In the mitochondrial matrix.
Allosteric inhibitor
Indirectly induces a conformational change to the active site.
Competitive inhibition
Inhibitor molecule competes with the substrate for binding to the active site.
The electron transport chain is present in multiple copies in where in prokaryotes and eukaryotes?
Inner mitochondrial membrane for eukaryotes. In the plasma membrane of prokaryotes.
Endergonic reactions require the ______ of energy, while exergonic reactions ______ energy.
Input;release.
Glycolysis has three stages. What are they?
Investment, Cleavage and Energy harvest.
What does it mean if an enzyme is denatured and why can this happen (2)?
It cannot work properly because it will become distorted if it's put out of its environment and ideal conditions. Most enzymes thrive in a certain environment with specific pH or temperature. Ex: An enzyme in your stomach lives in an acidic environment specific to your stomach. If the conditions were to change the enzyme could become denatured without it's ideal conditions which would make it obsolete.
In glycolysis if it stays anaerobic, it produces...(2)
Lactic acid fermentation (lactase dehydrogenase) or alcoholic fermentation to produce ethanol.
Lactic Acid Fermentation (2)
Lactic acid fermentation converts the 3-carbon pyruvate to the 3-carbon lactic acid (C3H6O3) and regenerates NAD+ in the process. Allowing glycolysis to continue to make ATP in low-oxygen conditions.
Lactase dehydrogenase is also known as...
Lactic acid fermentation.
Which fermentation method can occur in animal skeletal muscles?
Lactic acid fermentation.
______ fermentation is what causes mammalian skeletal muscles to fatigue.
Lactic acid.
The last step of aerobic respiration is referred to as what?
Oxidative phosphorylation.
Lose Electrons = __________ and Gain Electrons = __________.
Oxidized; reduced.
_____ is an essential element in the electron transport chain and aerobic respiration.
Oxygen
What is the final electron receptor in oxidative phosphorylation?
Oxygen.
When energy-depleted elements associated with a __________ are accepted by an organic molecule, the process is called _____________ and the end product of glycolysis is ____________.
Photon;fermentation;ATP.
When the molecules in food are broken down during digestion, it releases the inherent _____ within their chemical bonds.
Potential energy.
Fermentation
Process by which cells make ATP without the presence of oxygen to continue glycolysis.
Cellular Respiration
Process that releases energy by breaking down glucose and other food molecules in the presence of oxygen (glycolysis).
ATP synthase
Produced from the electron transport chain. It combines a phosphate with ADP to create ATP at the end of cellular respiration in the mitchondria.
Lactic acid
Product of fermentation in many types of cells, including human muscle cells.
Positive change (2)
Products have more free energy than the reactants. Ex: Endergonic is spontaneous
Not all _____________ cells can do photosynthesis.
Prokaryotes.
ATP
The energy source that cells use for most of their work and also known as energy currency.
Investment
Some ATP energy is used to start the process of glucose oxidation at the beginning of the cycle.
Second Law of Thermodynamics
States that every energy transfer involves some loss of energy in an unusable form (usually heat).
Potential energy
Stored energy that results from the position or shape of an object.
Thermodynamics
Study of energy and energy transfer involving physical matter.
Everything outside to that matter is the _________.
Surroundings.
ATP is a type of nucleic acid. T or F
T.
Each citric acid cycle will produce two carbon dioxide molecules and one ATP molecule. T or F
T.
Most enzymes are proteins. T or F
T.
The Citric Acid Cycle is aerobic. T or F
T.
Where does electron transport take place?
Takes place in the cristae of the mitochondria.
Energy
The ability to do work.
Acetyl- coenzyme A
The acetylated form of coenzyme A. Formed as an intermediate in the oxidation of carbohydrates, fats, and protein in animal metabolism.
Activation Energy
The amount of initial energy necessary for reactions to occur.
When muscle cells run out of oxygen, what happens to the potential for energy extraction from sugars and what pathways do the cell use (4)?
The cells follow the lactic acid fermentation pathway. Without oxygen, oxidative phosphorylation and the citric acid cycle would stop. So ATP is no longer generated through that this mechanism, which extracts the greatest amount of energy from a sugar molecule. In addition, NADH accumulates, preventing glycolysis from going forward because of the absence of NAD+. Lactic acid fermentation uses the electrons in NADH to generate lactic acid from pyruvate, which allows glycolysis to continue and thus a smaller amount of ATP can be generated by the cell.
Negative change (2)
The products of a reaction have less free energy than the reactants. Ex: Exergonic reaction where the energy is exiting.
Substrates
The specific reactants (substance) that an enzyme binds and acts on.
First Law of Thermodynamics (2)
The total amount of energy in the universe is constant and conserved. Energy can be transferred from place to place or transformed in different forms, it cannot be created or destroyed.
Kinetic energy
The type of energy associated with objects in motion.
Feedback inhibition (3)
Uses a reactant product to regulate its own further production. Production of both amino acids and nucleotides are controlled by feedback inhibition.
Free energy is ________ or energy that is available to do __________.
Usuable;work.
Coenzyme A, which assists in the production of acetyl CoA during the citric acid cycle, is made from which vitamins?
Vitamin B₅.
Do prokaryotes not conduct the process of the citric acid cycle?
Yes.
Is electron transport aerobic?
Yes.
Is the digestive system very involved with enzymes?
Yes.
