RESPIRATION

Question 1

Where does glycolysis happen in the cell

Answer 1

Cytoplasm

Question 2

Describe stages of glycolysis

Answer 2

Glucose — glucose diphosphate (2 ATP = 2ADP)

Glucose diphosphate - 2x triose phosphate

• substrate level phosphorylation *
  2x triose phosphate — (phosphate added) 2x triose bisphosphate
  ((2ADP = 2ATP, 2NAD = 2RED NAD by dehydrogenase enzyme) 2x))

Triose bisphosphate — 2x pyruvate

Question 3

What are the products of glycolysis

Answer 3

2x RED NAD
Net gain 2 ATP
2x Pyruvate

Question 4

Describe process of link reaction

Answer 4

Pyruvate is converted into acetylcoenzyme A

By decarboxylation - co2 and dehydrogenation - red NAD to form acetyl group

Question 5

Describe process of Krebs cycle

Answer 5

AceCoA from link reaction is added to a 4 carbon acid to create a 6 carbon compound, CoA is regenerated

6 carbon acid is dehydrogenated = red NAD + decarboxylated = co2 to make 5 carbon acid

5 carbon acid is dehydrogenated = red NAD, FAD + decarboxylated = co2 to make 4 carbon acid

4 carbon acid can combine with AceCoA and repeat cycle

Question 6

Where does electron transport chai (oxidative phosphorylation) occur in

Answer 6

Cristae

Question 7

Describe process of ETC / oxidative phosphorylation

Answer 7

• RED NAD/FAD releases protons and electrons
• electrons enters ETC and releases their energy to pump protons by active transport from cristae to inter membrane space
• high concentration of protons built in the inter membrane space
• chemiosmosis occurs = protons are pumped through ATP synthase to produce ATP
• oxygen acts as a terminal electron acceptor and reacts with protons and electrons to form water

Question 8

What are 2 types of fermentation

Answer 8

Lactate
Alcoholic

Question 9

Describe lactate fermentation in animals

Answer 9

Pyruvate — lactate (red NAD = NAD, lactate dehydrogenase) — glucose (oxygen debt to break down lactic acid)

Question 10

Describe alcoholic fermentation in plants and yeast

Answer 10

Pyruvate —ethanel (Pyruvate decarboxylase) — ethanol (red NAD = NAD)

Question 11

Explain why Beer is fizzy and wine is flat

Answer 11

Beer = co2 is dissolved

Wine = co2 is escaped

Question 12

Explain why yeast is used in bread

Answer 12

To rise it

Question 13

Explain how ethanol is not toxic in bread

Answer 13

It is dissolved when baking due to high temperature