chap 5 Flashcards
what is a catabolic reaction and what does it use/produce?
- exergonic
- energy releasing
- uses glucose to make atp
what is an anabolic reaction and what does it use/produce?
- endergonic
- energy consuming(atp)
- larger complex molecules (protein)
atp formation
- uses energy from catabolism
atp hydrolysis
- breakdown of atp
- break atp to use energy for anabolic reaction
what carries electrons throughout catabolic and anabolic rxns?
Hydrogen ions in NAD/NADH and FAD/FADH
oxidation
loss of electrons
reduction
gain of electrons
substrate level phosphorylation
- most simple level
- just add a phosphate group to adp to make atp
oxidative phosphorylation
-requires electron transport chain
- use of proton gradient
photo-phosphorylation
- requires electron transport
- uses the proton gradient
- uses light
respiration
-uses electron transfer chain and terminal electron transfer
- can be aerobic(o2 acceptor) or anaerobic(NO3- acceptor)
fermentation
-anaerobic
- incomplete oxidation of carbohydrate
- no electron acceptor so oxidize NADH to small organics acids and alcohol
stages of respiration
- Glycolysis
- acetyl-coa formation
- krebs cycle
- electron transport chain
Glycolysis(emden-meyerhof pathway)
-oxidation of glucose to pyruvic acid
- atp via substrate lvl phosphorylation
- net gain : 2 atp, 2 nadh, 2 pyruvate
entner - doudoroff pathway
sugar acids catabolism pathway
in gram negative
pentose phosphate shunt
produce pentose sugars for production of aromatic amino acids, nucleotide, and pyruvate
Acetyl CoA Formation
- pyruvate oxidation to acetyl - CoA
- 1 nadh formed
Krebs Cycle
- glucose oxidized to final
- gain 3 NADH/1 FADH2/1 ATP per acetyl CoA
- gain 6 NADH/ 2 FADH2/ 2 ATP per glucose
electron transport chain
- electrons gained from glucose contain in NADH and FADH2
- atp synthesis via chemiosmosis( form of oxidative phosphorylation)
- proton gradient( uses energy from proton gradient to make atp)
- 1 NADH -> 3ATP and 2 FADH2 -> 2 ATP
election transfer chain molecules
flavoproteins, cytochromes(heme containing protiens), ubiquinones
how much atp does oxidative phosphorylation produce in cellular respiration and what is oxidized?
NADH and FADH2 oxidized
34 ATP made
how much atp is produced from substrate level phosphorylation?
4 ATP
anaerobic respiration
- final electron acceptor is an inorganic substance(nitrate and sulfate most common)
- less energy yield than aerobic respriation
-autotroph
grow on CO2
-heterotroph
use complex carbon
what forms lactic acid?
streptococcus, lactobacillus
what causes alcohol fermentation?
yeast and many bacteria
what can be used for metabolism other than carbohydrates?
proteins and fats
what organisms use oxygenic photosynthesis?
cyanobacteria, algae, and plants
anoxygenic photosynthesis
- used by purple sulfur and green sulfur bacteria
6CO2 + 12 H2S + Light energy -> C6H12O6 + 6H2O + 12S
autotrophs
organisms convert light into chemical energy; and covert CO2 to organic compounds
light dependant reactions
- pt1 of photosynthesis
light, H2O -> O2 + Energy or Light H2S -> S + energy
light-independent reactions
- pt2 of photosynthesis
CO2 + energy -> complex organic molecules
what light absorbing pigment does oxygenic vs anoxygenic use?
oxygenic - chlorophyll
anoxygenic - bacteriochlorophylls
Photosystem 2
- Light stimulates everything
- H2O loses e- and becomes a strong oxidizing agent and kicks off the electron transport chain
Photosystem 1
- excited electrons produce NADPH
- no proton gradient
What is the electron flow in oxygenic photosynthesis?
H2O -> PS2 -> PS1 -> NADP+
green sulfur bacteria photosynthesis
- only use PS1
- use sulfur compounds, H2, as electron donors
- autotrophic
purple non-sulfur bacteria photosynthesis
- use only PS2 and cyclic photophosphorylation
- are photoheterotrophs
Calvin-Benson cycle
- converts CO2 into sugars
- no need direct light
- has ribulose(rubisco, CO2 fixing enzyme)
- key intermediate: glyceraldehyde-2-P
- requires a lot of energy(ATP/NADPH)
