TSH, LH, FSH and hCG are glycoprotein hormones. The biological specificity of each hormone is determined by:

• A The identical alpha subunit
• B A separate signal peptide
• C The carbohydrate moiety alone
• D The unique beta subunit ✓

Explanation

The four glycoprotein hormones share a nearly identical alpha subunit, but each has a distinct beta subunit that confers receptor specificity and biological activity. The beta subunits can even be combined experimentally with a foreign alpha chain to generate functional hormone. This is why assays target the beta subunit: beta-hCG measurement in pregnancy exploits the unique beta chain to avoid cross-reactivity with LH.

Reference: Harper's Illustrated Biochemistry, 32nd ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

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