Lab 4: Pathway Building – Glycolysis
Theory based lab focusing on key mechanisms within the glycolysis pathway (dry)
Lab Objectives:
Examine the structural components of the transformation of carbohydrates into energy
Compare the differences in the reverse process to recreate carbohydrates for storage.
Part 1 - Designing your worksheets
Before we get into the actual poster building, we will first go through a series of questions designed to
prepare you for the final version when we use the poster sheets.
To begin, we will fill in the following diagram with steps learned from this week's worksheets (attached).
Question 1: (10 points) Fill in boxes labelled Q1 on worksheets 7 and 8 with its corresponding structures
and enzymes. Red boxes indicate structures, black boxes indicate enzymes
Gluconeogenesis does not always use the same enzymes to go in the reverse direction of glycolysis.
Question 2: (3 points) List the steps that are unique to Gluconeogenesis
Steps 1, 3 and 10 are the steps that exist in glycolysis but not in gluconeogenesis.
Step 1 - Glucose ---> glucose 6-phosphate
Step 3 - Fructose 6-phosphate ---> fructose 1,6-bisphosphate
Step 10 - phosphoenolpyruvate ---> pyruvate
Question 3: (3 points) Provide an explanation for why different steps in this process are needed.
Several reactions in glycolysis must differ from those in gluconeogeneis because the equilibrium of
glycolysis lies far to the side of pyruvate formation. The steps that differ in glycolysis are the
regulatory steps of glycolysis.
Although this pathway starts with glucose, the majority of sugar that we take in is not glucose. Apart
from starches, humans take in a large amount of sugar as sucrose (table sugar), lactose from milk, and
fructose from corn syrup. Let’s breakdown each of these sugars and figure out how they build into our
map
1CHEM-330
, Let’s start with breaking down each of these sugars
Question 4: (2 points) Sucrose is composed of what 2 sugars?
-Glucose and fructose
Question 5: (3 points) Provide the structure of Sucrose
Question 6: (2 points) Lactose is composed of what 2 sugars?
-Galactose and glucose
Question 7: (3 points) Provide the structure of Lactose
Now that we know the structure of Sucrose and Lactose, we can begin to figure out how they add into
our diagram from earlier. Sucrose can be broken down into glucose and fructose by the enzyme Sucrase.
This gives use a direct entry for one of those sugars.
2CHEM-330
Theory based lab focusing on key mechanisms within the glycolysis pathway (dry)
Lab Objectives:
Examine the structural components of the transformation of carbohydrates into energy
Compare the differences in the reverse process to recreate carbohydrates for storage.
Part 1 - Designing your worksheets
Before we get into the actual poster building, we will first go through a series of questions designed to
prepare you for the final version when we use the poster sheets.
To begin, we will fill in the following diagram with steps learned from this week's worksheets (attached).
Question 1: (10 points) Fill in boxes labelled Q1 on worksheets 7 and 8 with its corresponding structures
and enzymes. Red boxes indicate structures, black boxes indicate enzymes
Gluconeogenesis does not always use the same enzymes to go in the reverse direction of glycolysis.
Question 2: (3 points) List the steps that are unique to Gluconeogenesis
Steps 1, 3 and 10 are the steps that exist in glycolysis but not in gluconeogenesis.
Step 1 - Glucose ---> glucose 6-phosphate
Step 3 - Fructose 6-phosphate ---> fructose 1,6-bisphosphate
Step 10 - phosphoenolpyruvate ---> pyruvate
Question 3: (3 points) Provide an explanation for why different steps in this process are needed.
Several reactions in glycolysis must differ from those in gluconeogeneis because the equilibrium of
glycolysis lies far to the side of pyruvate formation. The steps that differ in glycolysis are the
regulatory steps of glycolysis.
Although this pathway starts with glucose, the majority of sugar that we take in is not glucose. Apart
from starches, humans take in a large amount of sugar as sucrose (table sugar), lactose from milk, and
fructose from corn syrup. Let’s breakdown each of these sugars and figure out how they build into our
map
1CHEM-330
, Let’s start with breaking down each of these sugars
Question 4: (2 points) Sucrose is composed of what 2 sugars?
-Glucose and fructose
Question 5: (3 points) Provide the structure of Sucrose
Question 6: (2 points) Lactose is composed of what 2 sugars?
-Galactose and glucose
Question 7: (3 points) Provide the structure of Lactose
Now that we know the structure of Sucrose and Lactose, we can begin to figure out how they add into
our diagram from earlier. Sucrose can be broken down into glucose and fructose by the enzyme Sucrase.
This gives use a direct entry for one of those sugars.
2CHEM-330
