Bio Chapter 7

Question 1

Oxidation -

Answer 1

A substance loses electrons (becomes oxidized)

Question 2

Reduction -

Answer 2

A substance gains electrons (becomes reduced)

Question 3

Redox (what are the reducing/oxidizing agents) -

Answer 3

Reducing agent - electron donor
Oxidizing agent - electron acceptor
The more electronegative molecule is gonna steal electrons

Question 4

Example of redox (NaCl) -

Answer 4

Na + Cl -> Na+ + Cl-
Na becomes oxidized because it loses electron
Cl becomes reduced because it gains electron

Question 5

Cellular Respiration Reaction -

Answer 5

C6 H12 O6 + 6 CO2 -> 6 CO2 +6 H2O + Energy
C6 H12 O6 becomes oxidized (loses electron)
6 CO2 becomes reduced (gains electron)

Question 6

Electron carriers -

Answer 6

Also called cofactors or coenzymes
Provide the energy required for endergonic reactions

Question 7

Types of electron carriers -

Answer 7

ATP (adenosine triphosphate)
GTP (guanosine triphosphate)
NADH (nicotinamide adenosine dinucleotide)
- NADH is the reduced form, NAD+ is oxidized form
FADH2 (flavin adenine dinucleotide)
- FADH2 is reduced form, FAD+ is oxidized form

Question 8

Glycolysis -

Answer 8

Happens in the presence or absence of oxygen
Occurs in the cytoplasm
Net production: 2 ATP, 2 NADH, 2 pyruvate

Question 9

Pyruvate oxidation -

Answer 9

Occurs in the mitochondria in eukaryotes
Happens in the presence of oxygen
Net Products - For each 3 carbon pyruvate molecule: 1 CO2, 1 NADH, 1 acetyl-CoA > moves into citric acid cycle

Question 10

Citric acid cycle (Kreb’s cycle, tricarboxylic acid cycle) -

Answer 10

Occurs in matrix of mitochondria
Acetyl-CoA + oxaloacetate -> citrate
Products: 2 molecules of CO2 are released, 3 NAD+ are reduced to NADH, 1 FAD is reduced to FADH2, 1 ATP is produced (after GTP is produced, Oxaloacetate is regenerated)

Question 11

Electron transport chain -

Answer 11

Embedded in the inner mitochondrial membrane
Electrons from NADH and FADH2 are transferred to complexes of the electron transport chain
Each complex: Proton pump creating a proton gradient, transfers electrons to the next carrier

Question 12

Terminal electron acceptor -

Answer 12

Oxygen - its role in the oxidation of glucose

Question 13

Total ATP produced in cellular respiration -

Answer 13

30-32 molecules

Question 14

Autotrophs -

Answer 14

Fix CO2 and assemble it into organic molecules
Mainly sugars

Question 15

Heterotrophs -

Answer 15

Rely on other organisms to form organic compounds that they can then use as carbon sources

Question 16

Fermentation -

Answer 16

A partial degradation of sugars that occurs without O2, final electron acceptor is an organic molecule

Question 17

Lactic acid fermentation -

Answer 17

Occurs in muscle cells when O2 is limited, mammal red blood cells and some bacteria
No CO2 is produced
Used in yogurt production

Question 18

Alcohol fermentation -

Answer 18

Performed by anaerobic yeast species and bacteria
Two steps: Pyruvate is converted to CO2 and acetaldehyde, Acetaldehyde is converted to ethanol