4.1 INTRODUCTION TO CELLULAR RESPIRATION & FERMENTATION

Question 1

Products o f photosynthesis
(sugars and O2) are used in

Answer 1

energy releasing reactions in
aerobic cells

Question 2

Potential energy extracted from
food through

Answer 2

oxidation is used to
synthesize ATP

Question 3

Chemical energy (now stored in
ATP) can be

Answer 3

can be readily released
and used by cells

Question 4

When O2 is unavailable , anaerobic cells have

Answer 4

alternative ways to release energy from food molecules

Question 5

Aerobic Cellular Respiration

Answer 5

A process that extracts energy from food in the presence of O2

The energy is used to synthesize ATP from ADP + Pi

Question 6

Aerobic Cellular Respiration takes place in

Answer 6

Takes place in most Eukaryotes and some Prokaryotes

Question 7

Obligate Aerobe

Answer 7

an organism that must have oxygen to live
(Ex . humans)

Question 8

Obligate Anaerobe

Answer 8

an organism that cannot survive in an environment with oxygen (Ex . some species o f bacteria)

Question 9

Facultative Anaerobes

Answer 9

An organism that can survive with or w/o O2
(Ex . yeast and E . coli bacteria living in your gut)

Question 10

4 stages of Aerobic Cellular Respiration

Each stage involves the transfer of free energy, producing ATP in one of two ways:

Answer 10

1. Substrate-level Phosphorylation

Forms ATP directly in an enzyme-catalyzed rxn through the trans fer o f a phosphate group from one molecule to an ADP molecule

2. Oxidative Phosphorylation

Forms ATP indirectly through a series o f redox rxns involving a final electron acceptor

• In Aerobic Cellular Respiration, OXYGEN is
  the final electron acceptor

Question 11

1.Glycolysis (in cytosol)

Answer 11

‒ Enzymes split glucose into 2 pyruvate molecules

‒ 2 ATP and 2 NADH are synthesized
(via substrate-level phosphorylation)

Question 12

2.Pyruvate Oxidation (in mitochondria)

Answer 12

‒ Each pyruvate is oxidized, producing CO2 (waste), NADH and Acetyl-CoA

(acetyl group + coenzyme A)

Question 13

3.Citric Acid Cycle (in mitochondria)

Answer 13

‒ Acetyl-CoA enters a metabolic cycle, where the acetyl group is oxidized to CO2

‒ ATP, NADH, and FADH2 are synthesized

• (via substrate-level phosphorylation)

Question 14

4.Electron Transport / Oxidative
Phosphorylation (in mitochondria)

Answer 14

‒ NADH and FADH2 are oxidized

‒ High energy e- and H+ are passed from one
oxidizing agent to the next until they are
transferred to O2, producing H2O

‒ Free energy released during electron transport
is indirectly used to make ATP by Oxidative Phosphorylation

Question 15

Organelle involved in the
production of ATP

Answer 15

Mitochondrial

Question 16

The mitochondria is made of…

Answer 16

Made of 2 membranes
(outer and inner)

Question 17

Intermembrane space is

Answer 17

the space b /w the outer and inner

Question 18

Matrix is

Answer 18

the interior aqueous
environment of a mitochondria

Question 19

Some prokaryotes undergo _________ _________ ________________ without ____________

Answer 19

aerobic cellular respiration without mitochondria

Question 20

Glycolysis, Pyruvate Oxidation, and the Citric Acid Cycle
occur in

Answer 20

the cytosol

Question 21

Electron Transport occurs on

Answer 21

internal membranes

Question 22

Anaerobic Pathways

Answer 22

Many organisms (e.g.,
prokaryotes and protists) can
extract energy from food w/o using O2

Question 23

1. Anaerobic Respiration

Answer 23

Similar to aerobic, with a series o f steps, but uses an inorganic molecule other than O2 as the final oxidizing agent

Question 24

2. Fermentation

Answer 24

‒ Does NOT use an electron transpor t system

‒ Relies on an organic compound to act as the final
oxidizing agent

Question 25

Both Anaerobic Respiration and Fermentation are…

Answer 25

Both are catabolic (energy-yielding) processes

Released free energy (less than aerobic) is used
to make ATP