Bootcamp.com - Cellular Energy

_____ processes break down large macromolecules into smaller pieces, and usually release energy in the form of ATP

Catabolic processes break down large macromolecules into smaller pieces, and usually release energy in the form of ATP

(think catabolic = cannibalism)

_____ processes extract energy from ATP and use it to build larger, more complex macromolecules

anabolic

_____ is a unique type of potential energy, where the chemical bonds serve as a store of internal energy (U) and have the potential to be used to do work

chemical energy

(potential energy has to do with an object's position)

what is the most common form of "non-useful" energy release?

heat

_____ measures a system's useful, work performing energy

Gibbs free energy (G)

_____ describes a system's energy as it progresses from an initial to final state

free energy change (ΔG)

_____ is the energy associated with molecular bond energies

enthalpy (H)

change in enthalpy (ΔH) is the _____ between the initial and final states of a reaction

bond energy difference

a negative ΔH means that heat is _____, while a positive ΔH implies that heat is _____

released; absorbed

catabolic reactions release free energy (_____), so they are an example of an _____ reaction

-ΔG; exergonic

reactants (initial position) contain more internal energy than the products (final state) in _____ reactions

exergonic

EXergonic reactions mean that free energy is _____ the system

EXiting

exergonic reactions are _____

spontaneous

anabolic reactions absorb free energy (_____), so they are an example of an _____ reaction

+ΔG; endergonic

reactants (initial state) contain less internal energy than the products (final condition) in _____ reactions

endergonic

endergonic reactions are _____ reactions

non-spontaneous

if ∆G is _____, the reaction can occur spontaneously

negative

if ∆G is _____, the reaction is non-spontaneous

positive

a system with a higher Gibbs free energy is considered _____ stable

less

a system with a lower Gibbs free energy is considered _____ stable

more

ATP is an _____ nucleoside triphosphate

RNA

write the overall chemical formula for aerobic cellular respiration:

C₆H₁₂O₆ + 6O₂ → 6CO₂ + 6H₂O

ATP has 3 phosphates covalently linked to a _____ sugar, which also connects to an _____ nitrogenous base

ribose; adenine

_____ are the bonds found between phosphate groups

phosphoanhydride bonds

ATP molecules are _____ because the three phosphate groups are all negatively charged and repel each other

unstable

_____ is the cellular energy currency

ATP

ATP → ADP +Pi is a _____ reaction

hydrolysis

ATP hydrolysis reactions release free energy, making them _____ and _____

spontaneous; exergonic

ADP + Pi → ATP is a _____ reaction

condensation

condensation reactions absorb free energy, making them _____ and _______

non-spontaneous; endergonic

ATP provides energy for all cells by transferring _____ from ATP to another molecule

phosphate

(reaction coupling)

_____ links unfavorable reactions with favorable ones, as long as the net free energy change (ΔG) for the two reactions is negative (exergonic and spontaneous)

reaction coupling

_____ make many ATP molecules through cellular respiration

mitochondria

where are mitochondria found in a eukaryotic cell?

floating in the cytosol

(as a component of the cytoplasm)

how many membranes do mitochondria have?

2

the inner mitochondrial membrane has many infoldings called _____ that increase the surface area

cristae

the acidic region between the outer and inner mitochondrial membranes is the _____

intermembrane space

the intermembrane space between the outer and inner mitochondrial membranes is the_____ region

acidic

the area deep to the inner mitochondrial membrane is the _____

mitochondrial matrix

Human muscle cells (myocytes) have a high energy requirement, so there are many _____ in them

mitochondria

Red blood cells (erythrocytes) function to carry as much oxygen as possible, therefore, they tend to not contain any _____

mitochondria

the mitochondrial matrix contains its own circular _____ and _____

DNA; ribosomes

the _____ says that the aerobic bacteria became mitochondria, while the photosynthetic bacteria became chloroplasts

endosymbiotic theory

the endosymbiotic theory says that the aerobic bacteria became _____, while the photosynthetic bacteria became _____

mitochondria; chloroplasts

aerobic cellular respiration is a sizable _____ pathway that requires _____

catabolic; oxygen

what are the 4 components of aerobic cellular respiration?

glycolysis; pyruvate manipulations; the Krebs cycle; oxidative phosphorylation

the 4 pathways of aerobic cellular respiration work to break _____ into carbon dioxide and water, with the generation of _____

glucose; ATP

the 4 pathways of aerobic cellular respiration work to break glucose into _____ and _____, with the generation of ATP

carbon dioxide; water

is aerobic cellular respiration overall endergonic or exergonic?

exergonic

is aerobic cellular respiration overall oxidative or reductive?

oxidative

_____ converts a six-carbon glucose molecule into 2 three-carbon compounds called pyruvate

glycolysis

glycolysis converts a six-carbon glucose molecule into _____ three-carbon compounds called _____

2; pyruvate

glycolysis does not depend on _____, which is why it can participate in fermentation as well

oxygen

In what location of the cell does glycolysis occur?

cytosol

NAD+/NADH is a _____ (organic cofactor)

coenzyme

glycolysis extracts high energy e- as glucose is broken down, using them to _____ NAD+ into NADH, which then may travel to the _____ for further ATP creation

reduce; electron transport chain (ETC)

glycolysis has 2 main phases: an _____ phase, and an _____ phase

energy investment; energy payoff

during glycolysis, hexokinase and the free energy released from 1 ATP hydrolysis to "trap" glucose in the cell as _____

glucose-6-phosphate

during glycolysis, isomerase is used to turn glucose-6-phosphate into _________

fructose-6-phosphate

during glycolysis _____ (enzyme) and the free energy released from _____ is used to make fructose-1,6-bisphosphate

phosphofructokinase; 1 ATP hydrolysis

what molecule breaks down into 2 G3P molecules?

fructose-1,6,bisphosphate

_________ is an essential regulatory enzyme of glycolysis

phosphofructokinase (PFK)

during the energy payoff phase of glycolysis G3P is oxidized and ____ is reduced

NAD+ (is reduced to NADH)

(makes 2 NADH - 1 for each step 6 that is occurring)

_____ uses ADP as a direct substrate for its phosphorylation into ATP

substrate-level phosphorylation

substrate-level phosphorylation occurs directly in the _____ during the energy payoff phase of glycolysis

cytosol

a _____ is an enzyme which phosphorylates a molecule, and it is responsible for the ADP phosphorylations of glycolysis

kinase

the energy payoff phase produces _____ ATP, _____ NADH and _____ pyruvate

4; 2; 2

list the net products of glycolysis from 1 glucose

2 ATP, 2 NADH, 2 pyruvate

if glycolysis makes 4 ATP, 2 NADH, and 2 pyruvates, why does glycolysis only produce a net of 2 ATP?

need to account for the 2 ATP used during the energy investment phase

list what molecules go into glycolysis initially:

1 glucose, 2 ATP

which group of 3 reactions link glycolysis to the rest of cellular respiration?

the pyruvate manipulation reactions

where do the pyruvate manipulation reactions occur?

in the mitochondrial matrix

pyruvate manipulations occur in the _____ for prokaryotes because they do not have membrane-bound organelles

cytosol

list the 3 separate reactions of the pyruvate manipulations:

1. decarboxylation; 2. oxidation; 3. add CoA

what enzyme catalyzes the pyruvate manipulation reactions?

the pyruvate dehydrogenase complex (PDC)

the pyruvate dehydrogenase complex (PDC) is composed of _____ enzymes, with 1 for each pyruvate manipulation

3

during pyruvate decarboxylation, pyruvate releases a carbon atom as _____

carbon dioxide

during pyruvate oxidation, the decarboxylation product is converted to a two-carbon _____

acetyl group

pyruvate oxidation is accompanied by the reduction of _____ to _____

NAD+ to NADH

pyruvate oxidation indirectly depends on _____

oxygen

(regenerates NAD+ in the ETC)

after the decarboxylation and oxidation steps of the pyruvate manipulations, the remaining acetyl group will bind to _________ and this results in the formation of __________

Coenzyme A (CoA), acetyl-CoA

list the net products of pyruvate manipulations from one glucose

2 CO₂, 2 NADH, 2 acetyl-CoA

where does the Krebs cycle take place in eukaryotes?

mitochondrial matrix

in prokaryotes, the Krebs cycle takes place in the _____

cytosol

the Krebs cycle has _____ intermediates and a total of _____ steps.

7; 8

the acetyl-CoA from the pyruvate manipulations merges with _____ to form citrate.

oxaloacetate

the acetyl-CoA from the pyruvate manipulations merges with oxaloacetate to form _____

citrate

_____ molecules are _____ by the Krebs cycle for every 1 glucose

2 acetyl-CoA; oxidized

_____ cycles of the Krebs cycle occur per glucose

2

what is the net production of 1 Krebs cycle

2 CO2, 3 NADH, 1 FADH2, and 1 ATP

what is the net production of 2 Krebs cycles (from 1 glucose molecule)?

4 CO2, 6 NADH, 2 FADH2, and 2 ATP

what is the waste product of the Krebs cycle?

CO₂

_____ encompasses two linked components - the ETC and chemiosmosis

oxidative phosphorylation

oxidative phosphorylation encompasses 2 linked components - the _____ and _____

ETC; chemiosmosis

_____ is the mechanism of ATP generation that occurs when energy is stored in the form of a H+ concentration gradient across a membrane

chemiosmosis

the ETC is in the _____ of eukaryotes

mitochondrial inner membrane/cristae

the ETC is in the _____ of prokaryotes

cell membrane

e- release energy through the ETC, which goes toward _____

H+ pumping

the ETC couples the _____ flow of e- with the _____ pumping of H+ across the inner mitochondrial membrane (eukaryotes)

exergonic, endergonic

which ETC proteins act as H+ pumps?

complex-I, III, and IV