chapter 5 and 6 flashcards
How many net ATPs are produced when prokaryotic cell oxidizes 1 glucose ?
32 ATP
how many net ATPs are made when eukaryotic cell oxidizes 1 glucose ? Why?
30 ATP (use 2 ATP to bring glucose into mitochondria) for eukaryotes
In cellular respiration, what Is the final electron acceptor if oxygen is not available?
pyruvate
Which intermediate in glycolysis is not a shared one in gluconeogenesis ?
Oxaloacetate (only in gluconeogenesis)
What are nucleophiles ?
nucleophiles are the species that use their electrons to attack other atoms and attach themselves to the atoms.
how is glucose used in muscle ?
glucose used as a Quick source of energy through ATP production
What are non-reducing sugars ?
. Non-reducing residues within sugars are those that do not have an OH at the anomeric carbon,
Where does gluconeogenesis occur?
Liver
What happens if glycogen cannot breakdown ?
if no glycogen breakdown occurs, no glucose is available to enter glycolysis
What happens to intracellular calcium during muscle contraction ?
intracellular calcium rises during muscular contraction
What activates glycogen phosphorylase?
glycogen phosphorylase activated by:
-muscular contraction (increased intracellular calcium)
-phosphorylation
what is glycogen phosphorylase used for ?
Glycogen breakdown
Can muscle release glucose into the bloodstream ?
No, because muscle lacks the enzyme glucose-6-phosphatase it is unable to convert glucose-6-P (produced during muscle glycogen breakdown) to uncharged glucose capable of crossing the muscle cell membrane. Thus muscle cannot release glucose to the bloodstream
Where is glycogen stored?
LIVER
where is fat stored?
Adipose tissue
What occurs in reciprocal regulation ?
Reciprocal regulation prevents futile cycles (glycogen synthesis and degradation) from running simultaneously
Where does glycolysis occur ? Does it require oxygen? What is electron carrier ?
Glycolysis occurs in CYTOSOL
-NO it does not require oxygen
-NAD
Why is PFK (phosphofructokinase) considered committed step ?
PFK commits the sugar fructose 1, 6 bisphosphate to glycolysis
What are the three enzymes that are part of committed steps in glycolysis ?
- Hexokinase
- PFK (phosphofructokinase)
- Pyruvate kinase (last step of glycolysis)
What occurs in the process of fermentation ?
Fermentation is the process by which NADH is oxidized to NAD+ under anaerobic conditions.
This reaction occurs with the generation of lactate from pyruvate and allows glycolysis to proceed in the absence of oxygen
What occurs in Krebs cycle?
The Krebs cycle oxidizes the two carbon equivalents of acetyl-CoA.
The carbon atoms that are oxidized to carbon dioxide in the Krebs cycle do not directly come from acetyl-CoA, but rather come from oxaloacetate (OAA)
How is Krebs cycle coupled to ETC (electron transport chain )?
Electron carriers from Krebs cycle are reduced.
Then the electron carriers from krebs are OXIDIZED in ETC
Which forms of energy do Krebs cycle produce
Krebs proudces energy in forms of NADH (3) and FADH2 (1)
What are structural isomers? Example ?
Structural isomers: two molecules with Different connectivity
example D glucose (aldose) and D fructose (ketone)
What are epimers?
epimers differ in configuration at a SINGLE chiral center
What are diastereomers ?
Diastereomers have opposite configuration at some but not all chiral centers
What are enantiomers ?
sugars that are mirror images if each other , and have opposite absolute configurations at all chiral centers
which forms do glucose predominantly exist?
glucose predominantly exists as:
-hexose
-aldose
-pyranose
