Biology - How Cells Harvest Chemical Energy

What are the two kinds of muscle fibers?

slow and fast muscle fibers

The percentage of types of fibers depends on:

the muscle and person

True or False: training can turn one runner into another

False

another name for slow muscle fibers:

slow-twitch fibers

most marathon runners have ___% slow fibers

80

what are the slow muscle fibers abundant in?

mitochondria and myoglobin molecules

What kind of color do myoglobin molecules give slow muscle fibers?

a reddish color

slow muscle fibers perform best in what kind of exercises?

endurance exercises

fast muscle fibers perform best in what kind of exercises?

short, intense exercises

most sprinters have ___% fast fibers

60

slow muscle fibers use ___ respiration, while fast muscle fibers use ____ respiration

aerobic, anaerobic

fast fibers have less ____ and ____, but produce this:

mitochondria, myoglobin, lactate

catabolic pathways:

break down energy

respiration is the transferring of ___ from ____ to ____.

hydrogen, glucose, oxygen

net reaction of cellular respiration:

C6H12O6 + 6O2 → 6CO2 + 6H2O + Energy (ATP + Heat)

reactions involving the transfer of one or more electrons from one reactant to another:

redox reactions

the loss of electrons:

oxidation

the addition of electrons:

reduction

what does OIL RIG stand for?

oxidation it loses

reduction it gains

ionic bonds involve the ____ transfer of electrons

complete

the electron donor is also known as the:

reducing agent

the electron acceptor is also known as the:

oxidizing agent

why are carbs and fats important fuels?

have lots of electrons and hudrogens

the three stages of cellular respiration are?

glycolysis, the citric acid cycle, the electron transport chain

this pathway is found in ALL organisms:

glycolysis

glycolysis is the breaking down of what molecule?

glucose

what gives glycolysis energy?

ATP

there are __ steps in glycolysis

10

what are the two phases of glycolysis?

the energy investment phase and the energy payoff phase

how many ATP molecules are invested in glycolysis?

2

in the energy investment phase, glucose is broken down into:

2 three carbon G3P molecules

what does G3P stand for?

glyceraldehyde 3-phosphate

in the energy payoff phase, how many ATP molecules are produced?

4

in the energy payoff phase, the 2 G3P molecules are converted to what?

2 three carbon pyruvate molecules

energy investment phase equation:

glucose + 2ATP → 2G3P

energy payoff phase equation:

2G3P → 2 pyruvate, 2H2O, 2NADH, 4ATP

net reaction of glycolysis:

glucose → 2 pyruvate, 2H2O, 2NADH, 2ATP

how much of glucose’s energy does glycolysis release?

less than a quarter

glycolysis does not require this molecule, making it:

oxygen, anaerobic

mitochondria are organelles that:

carry out cellular respiration

mitochondrian are _-_ __ long

1, 10, um

number one:

cristae (inner membrane)

number two:

outer membrane

number three:

intermembrane space

number four:

matrix (liquid part)

why does the inner membrane have so many folds?

increases surface area and ability to produce ATP

the mitochondrial matrix contains:

enzymes, DNA, ribsomes

the step between glycolysis and the citric acid cycle is:

conversion of pyruvate to acetyl CoA

when pyruvate loses a carbon, what is it release as?

CO2

after pyruvate loses a carbon, the remaining two combine with what to form acetyl CoA?

coenzyme A

acetyl CoA stands for:

acetyl coenzyme A

equation of pyruvate to acetyl CoA:

pyruvate, NAD+, coenzyme A → acetyl CoA, NADH, CO2

for each glucose molecule that entered glycolysis, these many acetyl CoA molecules enter the citric acid cycle:

2

these enzymes remove two hydrogens from the substrate:

dehydrogenases

what do dehydrogenases give NAD+?

two electrons and a proton, the other proton is released as a hydrogen ion

the structure of NAD+ is 2 ___ joined together by their ____

nucleotides, phosphate group

other names for the citric acid cycle include:

the tricarboxylic acid cycle, the krebs cycle

where does the citric acid cycle take place in the mitochondria?

the matrix

the citric acid cycle has __ steps

8

in the citric acid cycle, the carbons from acetyl CoA bond to __ to form __

four carbon oxaloacetate, six carbon citrate

what is the role of coenzyme A in the citric acid cycle?

helps the two carbons enter the cycle and is recycled

the citric acid cycle is called a cycle because oxaloacetate ___ to repeat the cycle.

regenerates

citric acid cycle equation (full equation with 2 puruvate)

2 pyruvate → 4CO2, 6NADH, 2FADH2, 2ATP

the citric acid cycle completes what?

the breakdown of glucose

the final stage of cellular respiration is:

oxidative phosphorylation

the two parts of oxidative phosphorylation are:

the electron transport chain and chemiosmosis

where does oxidative phosphorylation occur in the mitochondria?

the inner mitochondrial membrane

each electron transport chain has:

3 main multiprotein complexes and 2 mobile carrier proteins

what molecules carry the electrons extracted from food?

NADH and FADH2

in the electron transport chain, what atom takes the electrons at the end?

a highly electronegative oxygen atom

the production of ATP occurs from this:

energy released from diffusion of H+ ions from the intermembrane space to the matrix

the two functions of the electron transport chain include easing the fall of electrons from ___ to ___, and to release ___ ions into the ______

food, oxygen, H+, intermembrane space

chemiosmosis is an ____ mechanism

energy-coupling

chemiosmosis involves using the energy released by the ___ of __ ions used to fuel the __ of __ to create __

diffusion, H+, phosphorylation, ADP, ATP

oxidative phosphorylation makes around __ ATP

34

1 glucose molecule → __ ATP molecules

38

most electrons’ route throughout cellular respiration:

food → NADH → electron transport chain → oxygen

efficiency of respiration is __%

40

the two different kinds of phosphorylation are:

substrate-level phosphorylation and oxidative phosphorylation

this kind of phosphorylation involves an enzyme DIRECTLY giving a phosphate group from a substrate to ADP

substrate-level phosphorylation

substrate-level phosphorylation produces how many ATP molecules during cellular respiration?

6

this kind of phosphorylation involves an enzyme transferring an inorganic phosphate from the outside solution to ADP:

oxidative phosphorylation

oxidative phosphorylation creates how many ATP molecules during cellular respiration?

around 34

in aerobic conditions, the citric acid cycle occurs after glycolysis. in anaerobic conditions, what happens after glycolysis?

fermentation

Fermentation regulates the supply of this molecule in order to keep glycolysis going:

NAD+

the two kinds of fermentation are:

alcohol fermentation and lactic acid fermentation

in this kind of fermentation, pyruvate is converted into ethanol in two steps:

alcohol fermentation

the first step in alcohol fermentation involves the release of __, leading to the two carbon compound ____

CO2, acetaldehyde

in the second step of alcohol fermentation, acetaldehyde is reduced to what molecule?

ethanol

alcohol fermentation equation:

pyruvate + NADH → ethanol + CO2 + NAD+

examples of alcohol fermentation include:

bacteria, yeast, beer

in this kind of fermentation, pyruvate is converted to lactate:

lactic acid fermentation

there is ___ step in lactic acid fermentation:

1

during lactic acid fermentation, what happens to pyruvate?

it is reduced by NADH to become lactate

examples of lactic acid fermentation:

cheese, yogurt, strenuous exercise

these organisms require oxygen for respiration:

obligate aerobes

these organisms require oxygen-free conditions:

obligate anaerobes

these organisms can make energy with or without oxygen:

facultative anaerobes

carbohydrates are ___ into ___, which enters __

hydrolyzed, glucose, glycolysis

Proteins are ___ into amino acids to make their own proteins, but excess ____ are converted into _____ of __ or _____

hydrolyzed, amino acids, intermediates, glycolysis, citric acid cycle