Ch 5 pt2 (cell respiration) Flashcards
input and output of glycolysis
use 2 ATP for the oxidation of glucose into pyruvic acid
net gain of glycolysis
2 ATP, 2 NADH
type of phosphorylation that occurs during glycolysis
substrate-level
2 alternatives to glycolysis, and what they produce
pentose phosphate pathway, entner-doudoroff pathway
- 1 ATP
- metabolic byproducts (like 5-C sugars)
- amino precursors
why a cell would undergo an alternative pathway to glycolysis
- if a cell is going to divide, it will need more 5-C sugars to make DNA
- amino acid precursors needed if cell will be synthesizing proteins
- gram neg undergo enner-duodoroff
how many times kreb’s cycle goes around for every glucose mlcl
twice
input and output (and energy balance) of kreb’s cycle
(pyruvate loses a CO2 mlcl–>) Acetyl CoA enters cycle
output=6 CO2 lost
for every 1 glucose (after going around twice, once for each pyruvic acid), 2ATP, 2FADH, 8 NADH, 6 CO2
NAD to NADH is oxidation or reduction
reduction
what kind of phosphorylation takes place during electron transport chain
oxidative-phosphorylation
why we breathe
bring in O2 to serve as final electron acceptor in electron transport chain
input and output of e- transport chain
input- O2
output- H2O
sum up steps in electron transport chain (what is dropped off)
NADH or FADH2 or chlorophyl drops off e- + hydrogen
(hydrogen transported across plasma membrane via proton pumps, build up in intermembrane (euk) or periplasmic (pork) space) creates concentration gradient, flow passively thro atp synthase
net gain of electron transport chain
34 ATP
total atp gained from cellular respiration
prokaryotes v. eukaryotes
38 ATP for every glucose (prokaryotes), eukaryotes=36 ATP
why eukaryotes produce 2 less ATP than prokaryotes
electron carriers have to be actively transported across 2 membranes to get to inner mitochondria
H moving down its concentration gradient thro ATP synthase is called
chemiosmosis
when a cell needs to make ATP in the absence of carbohydrates, it
switch over and use other macromolecules (lipid catabolism, protein catabolism)
what are amphilbolic pathways
metabolic pathways that function in both anabolism and catabolism (can go in either direction; double arrows)
how biosynthesis pathways work
diverted products from intermediate, catabolic pathways (like glycolysis) put into biosynthesis pathways
anabolism
fermentation products are waste products; what is the only reason a cell would undergo fermentation
regeneraton of 2NAD+ (goes back into glycolyisis to make more ATP)
type of phosphorylation that occurs during krebs cycle
substrate level phosphorylation
how much atp is spent first half of glycolysis
2
the krebs cycle is a series of
stripping electrons off pyurivic acid (oxidation)
where glycolysis occurs in euk v prok
euk- outside mitochondria in cytoplasm
prok- inside cytoplasm in cell
