Cellular Respiration and Photosynthesis

Question 1

2 types of cell respiration

Answer 1

• aerobic respiration (krebs cycle)
• anaerobic respiration

Question 2

metabolic pathway that breaks down glucose and produces ATP

Answer 2

cell respiration

Question 3

this pathway generates two pyruvate molecules, ATP, NADH and water from one glucose molecule.

Answer 3

glycolysis

Question 4

where does glycolysis occur?

Answer 4

cytoplasm

Question 5

what happens in step 1 of glycolysis and explain what happens here.

Answer 5

HEXOKINASE

ATP gives phosphate group to glucose = 6-phosphate or G6P

Question 6

what happens in step 2 of glycolysis and explain what happens here.

Answer 6

PHOSPHOGLUCOSE ISOMERASE

phosphoglucomutase changes G6P into another sugar that has the same atoms but in a different order. This sugar is called fructose 6-phosphate, or F6P.

Question 7

what happens in step 3 of glycolysis and explain what happens here.

Answer 7

PHOSPHOFRUCTOKINASE

A second ATP molecule is consumed by the kinase phosphofructokinase to attach a phosphate group to F6P, resulting in fructose 1,6-bisphosphate or FBP.

Question 7

what happens in step 4 of glycolysis and explain what happens here.

Answer 7

ALDOLASE

The enzyme aldolase breaks fructose 1,6-bisphosphate into a ketone and an aldehyde molecule. These sugars, dihydroxyacetone phosphate (DHAP) and glyceraldehyde 3-phosphate (GAP), are isomers of each other.

Question 8

what happens in step 5 of glycolysis and explain what happens here.

Answer 8

TRIOSEPHOSPHATE ISOMERASE

The enzyme triose-phosphate isomerase quickly transforms DHAP into GAP (these isomers can switch). GAP is the substrate required for the next step of glycolysis.

Question 9

what happens in step 6 of glycolysis and explain what happens here.

Answer 9

GLYCERALDEHYDE-3-PHOSPHATE DEHYDROGENASE

The enzyme glyceraldehyde 3-phosphate dehydrogenase (GAPDH) has two functions: - dehydrogenates GAP by transferring one of its hydrogen molecules to nicotinamide adenine dinucleotide NAD⁺, forming NADH + H⁺.
- adds a phosphate from the cytosol to the oxidized GAP to form 1,3-bisphosphoglycerate (BPG).

The process is repeated for both molecules of GAP produced in the previous step.

Question 10

what happens in step 7 of glycolysis and explain what happens here.

Answer 10

PHOSPHOGLYCERATE KINASE
Sticky Note Paper

Phosphoglycerokinase is an enzyme that transfers a phosphate from BPG to ADP to create ATP. This process occurs for each BPG molecule, leading to the production of two 3-phosphoglycerate (3 PGA) molecules and two ATP molecules.

Question 11

what happens in step 8 of glycolysis and explain what happens here.

Answer 11

PHOSPHOGLYCERATE MUTASE

The enzyme phosphoglyceromutase relocates the P of the two 3 PGA molecules from the third to the second carbon to form two 2-phosphoglycerate (2 PGA) molecules.

Question 11

what happens in step 9 of glycolysis and explain what happens here.

Answer 11

ENOLASE

Enzyme Enolase eliminates a water molecule from 2-phosphoglycerate to create phosphoenolpyruvate (PEP). This process occurs for each molecule of 2 PGA from Step 8.

Question 12

what happens in step 10 of glycolysis and explain what happens here.

Answer 12

PYRUVATE KINASE

In a process that occurs for each molecule of PEP, the Pyruvate Kinase enzyme transfers a P from PEP to ADP to create pyruvate and ATP. The outcome of this reaction is two ATP molecules and two pyruvate molecules.

Question 13

It oxidises glucose derivatives, fatty acids, and amino acids to CO2 via enzyme controlled steps.

Answer 13

Krebs Cycle