Question

Statement I: G-protein coupled receptors (GPCRs) are transmembrane proteins.
Statement II: Binding of specific hormones to their corresponding GPCRs on their extracellular side induces conformational change on their cytoplasmic side.
Choose the most appropriate answer from the options given below:

• A. Statement I is correct and Statement II is incorrect
• B. Statement II is correct and Statement I is incorrect
• C. Statement I and Statement II both are correct
• D. Statement I and Statement II both are incorrect

Hint:

GPCRs: 7 transmembrane domains.
Signal transduction: ligand binding \(\rightarrow\) conformational change \(\rightarrow\) G-protein activation.

Answer 1

The Correct Option is C

Step 1: Understanding the Concept:
GPCRs are a large family of receptors.
They are involved in signal transduction.

Step 2: Key Formula or Approach:
No specific formula.
Need to understand GPCR structure and function.

Step 3: Detailed Explanation:
Statement I: GPCRs are transmembrane proteins - correct.
They have seven transmembrane domains.
Statement II: Hormone binding on extracellular side induces conformational change on cytoplasmic side - correct.
This activates G-proteins.
Thus, both statements are correct.

Step 4: Final Answer:
Both Statement I and Statement II are correct.
Hence, the correct option is (C).