Glycolysis and Redox Reactions (lol good luck memorizing this shit)

Question 1

Describe what happens when glucose is burned in a flame

Answer 1

• it releases heat, carbon dioxide, and water

Question 2

What are redox reactions

Answer 2

• are a transfer of electrons
• a gain in electrons or hydrogen atoms is called a reduction
• the loss of electrons or hydrogen atoms is called oxidation
• LEO (lose electrons oxidation) the lion says GER (gaini electrons reduction)

Question 3

Why is NAD essential in redox reactions?

Answer 3

• NAD is an essential electron carrier in cellular redox reactions

Question 4

What happens in glycolysis, and where does it occur?

Answer 4

• glucose is converted to pyruvate in 8 enzyme mediated reactions
• For each glucose consumed: 2 pyruvate, 2 NADH + 2H+, and a net amount of 2 ATP are produced
• occurs in the cytoplasm

Question 5

Glycolysis: Step 1 (Hexokinase)

Answer 5

• glucose is converted to glucose 6-phosphate (G6P) using hexokinase
• this step adds a phosphate group to the 6’ carbon on glucose to trap it in the cell (negative charge)
• remove glucose from cytoplasm to allow more glucose to enter
• uses 1 ATP molecule

Question 6

Glycolysis: Step 2 (Phosphohexose Isomerase)

Answer 6

• G6P is made into fructose-6-phosphate (F6P) to create symmetry in the molecule using phosphohexose isomerase
• this will make it easier to break up into two 3-C molecules

Question 7

Glycolysis: Step 3 (Phosphofructokinase)

Answer 7

• F6P is converted to fructose-1,6-bisphosphate (FBP) using phosphofructokinase
• consumes 1 ATP

Question 8

Glycolysis: Step 4 (the start of energy-harvesting reactions)

Answer 8

• FBP is then split into two glyceraldehyde 3-phosphate (G3P)
• C-H oxidation/NAD+ reduction releases enough energy to be coupled to P-bond formation

Question 9

Glycolysis: Step 5 (Triose Phosphate Dehydrogenase)

Answer 9

• the two G3P molecules are converted to two 1, 3-bisphosphoglycerate (BPG) using triose phosphate dehydrogenase
• 2 phosphate groups are consumed (one for each newly formed molecule) and 2NAD+ are reduced to 2NADH

Question 10

Glycolysis: Step 6 (Phosphoglycerate Kinase)

Answer 10

• two BPG are converted to 2, 3-phosphoglycerate (3PG) using phosphoglycerate kinase
• consumes 2 ADP and converts it to 2 ATP (substrate level phosphorylation)

Question 11

Glycolysis: Step 7 (Phosphoglyceromutase)

Answer 11

• two 3PG are converted to 2-phosphoglycerate (2PG) using phosphoglyceromutase

Question 12

Glycolysis: Step 8 (Enolase)

Answer 12

• two 2PG are converted to two phosphoenolpyruvate (PEP) using enolase
• produces two H2O

Question 13

Glycolysis: Last Step (Pyruvate Kinase)

Answer 13

• two PEP are converted to two pyruvate molecules

- consumes 2 ADP and converts it into 2 ATP molecules (substrate level phosphorylation)

Question 14

Where does pyruvate oxidation occur?

Answer 14

• mitochondria

Question 15

What happens if there is a lack of oxygen in an animal?

Answer 15

• since there is no electron acceptor in the form of O2, Lactic Acid Fermentation occurs

Question 16

What happens if there is a lack of oxygen in an plant?

Answer 16

• since there is no electron acceptor in the form of O2, calcohol fermentation occurs in organisms such as yeast

Question 17

How is glycolysis regulated?

Answer 17

• main control point is phosphofructokinase (which is the enzyme which adds the second phosphate to a C6)
• it’s activity is inhibited by high [ATP] levels