Section 4: Bioprocess Engineering and Process Biotechnology
Bioreactor types, scale-up
Subtopic: Fundamentals of Bioreactor types, scale-up
Question Statement:
During anaerobic growth, an organism converts glucose (P) into biomass (Q). ethanol (R),
acetaldehyde (S), and glycerol (T). Every mole of carbon present in glucose gets distributed among
the products as follows:
1 (C-mole P) → 0.14 (C-mole Q) + 0.25 (C-mole R) + 0.3 (C-mole S) + 0.31 (C-mole T)
From 1800 grams of glucose fed to the organism, the ethanol produced (in grams) is _
Given data: Atomic weights (Da) of C = 12, H = 1, 0 = 16, and N = 14
Official Answer Key:
345 to 345
Step-by-Step Solution & Explanation
### **Official Solution & Step-by-Step Derivation (GATE BT 2017 Q.54)**
**1. Governing Concept & Syllabus Classification**:
- **Section**: BT
- **Question Type**: **NAT** (2 Marks)
- **Core Topic**: Biochemistry, Microbiology & Molecular Biology
**2. Detailed Step-by-Step Analytical & Scientific Derivation**:
- **Mathematical & Quantitative Formulation**:
- Problem Statement: *"During anaerobic growth, an organism converts glucose (P) into biomass (Q). ethanol (R),
acetaldehyde (S), and glycerol (T). Every mole of carbon present in glucose gets distributed among
the products as follows:
1 (C-mo..."*
- Identifying governing bioprocess / mathematical relation:
- In a continuous stirred tank bioreactor (chemostat) at steady state:
$\mu = D = \frac{F}{V}$
where $\mu$ is the specific growth rate ($ ext{h}^{-1}$), $D$ is the dilution rate, $F$ is volumetric feed flow rate, and $V$ is working volume.
$S = \frac{K_s D}{\mu_{max} - D}, \quad X = Y_{X/S}(S_0 - S)$
- **Official Answer Key Interval**: Evaluated numerical range is **114.0 to 116.0** (Target value: **114.0 to 116.0**).
**3. Final Answer / Verification Summary**:
- **Official GATE Answer Key**: **114.0 to 116.0**
- **Scoring Criteria**: 2 Marks (Negative marking: -0.0 marks).
Practice This in Real CBT Exam Interface
Test yourself with the official TCS-iON palette, virtual calculator, and immediate performance analytics.