Chapter 7.2: Glycolysis: Splitting Glucose

Question 1

What happens during the oxidation and ATP formation process of glycolysis?

Answer 1

 Each G3P is oxidized, transferring two electrons (and one proton) to NAD+ thus forming NADH  A molecule of Pi is also added to G3P to produce 1,3-biphosphoglycerate (BPG)  The phosphate incorporated can be transferred to ADP by substrate-level phosphorylation to yield ATP

Question 2

Where does glycolysis occur?

Answer 2

cytoplasm

Question 3

What happens in aerobic respiration and fermentation to oxidize NADH?

Answer 3

• Aerobic Respiration
  
  • Electrons are transferred through a series of membrane carriers, ultimately reducing oxygen and forming water
  • Occurs in the mitochondria of eukaryotic cells in the presence of oxygen
  • A significant amount of ATP is produced
• Fermentation
  
  • When oxygen is unavailable, an organic molecule can accept electrons
  • Include acetaldehyde in ethanolic fermentation or pyruvate in lactic acid fermentation

Question 4

Is the first half of glycolysis endergonic of exergonic?

Answer 4

endergonic

Question 5

What are the last 4 reaction of glycolysis for?

Answer 5

o Another four reactions convert BPG into pyruvate  The phosphates are transferred to ADP to yield two ATP per G3P

Question 6

What does the first half of glycolysis consist of?

Answer 6

o The first half of glycolysis consists of five sequential reactions that convert one molecule of glucose into two molecules of the 3-carbon compound glyceraldehyde 3-phosphate (G3P)

Question 7

What happens during the cleavage process of glycolysis?

Answer 7

 6-carbon diphosphate is then split into two 3-carbon monophosphate sugars  One is G3P and other is converted into G3P

Question 8

What happens during the priming reactions of glycolysis?

Answer 8

 First three reactions “prime” glucose by changing it into a compound that can be readily cleaved into two 3-carbon phosphorylated molecules  Two of these reactions transfer a phosphate from ATP (required 2 ATP)

Question 9

What happens in the second half of glycolysis?

Answer 9

o In the second half of glycolysis, five more reactions convert G3P into pyruvate in and energy yielding process that generates ATP

Question 10

How is NADH recycled?

Answer 10

The NADH is oxidized back to NAD⁺ through aerobic respiration or fermentation

Question 11

What is the net reaction of glycolysis?

Answer 11

• Glucose + 2 ADP + 2 P_i 2 NAD⁺ à 2 Pyruvate + 2 ATP + 2 NADH + 2 H⁺ + 2 H₂O

Question 12

What are the products of glycolysis?

Answer 12

net yield of two molecules of ATP, two molecules of NADH, and two pyruvate