Subtopic: Discrete & Continuous Probability Distributions
Question Statement:
Which of the following statement(s) regarding trafficking in eukaryotic cells
is(are) CORRECT?
Options:
(A) Dynamin binds GTP and is involved in vesicle budding
(B) Dynamin is involved in cytoskeletal remodelling
(C) Dynein binds ATP and is involved in movement of organelles along
microtubules
(D) Dynein binds GTP and is involved in movement of organelles along
microtubules
.55 Consider a random variable X with mean 𝜇 = 0.1 and variance 𝜎
ଶ = 0.2. A new
random variable Y = 2X + 1 is defined. The variance of the random variable Y
(rounded off to one decimal place) is _________________.
Official Answer Key:
A;C
Step-by-Step Solution & Explanation
### **Official Solution & Concept Analysis (GATE BT 2022 Q.54)**
**1. Governing Concept**:
- **Topic**: Cell Biology & Vesicular Protein Trafficking
- Intracellular vesicle budding and transport are directed by distinct protein coat complexes:
1. **COPII**: Mediates **anterograde transport** from the Endoplasmic Reticulum (ER) to the *cis*-Golgi.
2. **COPI**: Mediates **retrograde transport** from Golgi back to ER (retrieving ER-resident proteins with KDEL or KKXX signals) and between Golgi cisternae.
3. **Clathrin**: Mediates transport from the *trans*-Golgi network to endosomes/lysosomes and from the plasma membrane during receptor-mediated endocytosis.
**2. Option Analysis**:
- **Option (A) [COPII coats mediate anterograde transport from ER to Golgi] is CORRECT**: Canonical molecular role of the Sar1-Sec23/24-Sec13/31 COPII complex.
- **Option (B) is INCORRECT**: Inverts the directionality; COPI mediates retrograde transport, not anterograde.
- **Option (C) [KDEL receptor retrieves resident ER proteins from the Golgi back to the ER] is CORRECT**: Recognizes the C-terminal Lys-Asp-Glu-Leu motif in the acidic Golgi and packages proteins into COPI retrograde vesicles.
- **Option (D) is INCORRECT**: Clathrin coats do not mediate direct ER-to-Golgi budding.
**3. Final Answer**:
- **Correct Options**: **A, C**
Practice This in Real CBT Exam Interface
Test yourself with the official TCS-iON palette, virtual calculator, and immediate performance analytics.