To solve the question regarding the balance sheet for ATP production in glycolysis, we will analyze each step of the glycolysis pathway and determine the values for P, Q, R, and S.
### Step-by-Step Solution:
1. **Step 1: Glucose to Glucose-6-phosphate**
- In this step, 1 ATP is utilized to convert glucose to glucose-6-phosphate.
- Since no ATP is produced in this step, we denote this as X.
- Therefore, **P = 1** (ATP utilized) and **X = 0** (ATP produced).
2. **Step 2: Fructose-6-phosphate to Fructose-1,6-bisphosphate**
- Similar to the first step, this conversion also utilizes 1 ATP.
- Again, no ATP is produced in this step, so we denote this as X.
- Therefore, **Q = X** (ATP produced) which is 0, and we already know that 1 ATP is utilized.
3. **Step 3: 1,3-bisphosphoglyceric acid to 3-phosphoglyceric acid**
- In this step, 2 ATP are produced from the conversion of 1,3-bisphosphoglyceric acid to 3-phosphoglyceric acid.
- No ATP is utilized in this step.
- Therefore, **R = 2** (ATP produced) and **X = 0** (ATP utilized).
4. **Step 4: Phosphoenolpyruvic acid to Pyruvic acid**
- In this final step, 2 ATP are produced from the conversion of phosphoenolpyruvic acid to pyruvic acid.
- No ATP is utilized in this step.
- Therefore, **S = 2** (ATP produced) and **X = 0** (ATP utilized).
### Summary of Values:
- **P = 1**
- **Q = 0 (X)**
- **R = 2**
- **S = 2**
### Final Answer:
The correct values to fill in the blanks for P, Q, R, and S are:
- P = 1
- Q = 0 (X)
- R = 2
- S = 2
