Step 1: Understanding the Concept:
Human taste perception is mediated by specialized taste receptor cells on the tongue that detect five basic tastes: sweet, sour, salty, bitter, and umami.
Specific chemical structures and ions trigger these receptors, producing distinct taste sensations.
Step 2: Detailed Explanation:
Let us match each basic taste with its corresponding chemical compound:
- (A) Sour: Sour taste is elicited by hydrogen ions (\(\text{H}^+\)) released from acids.
Formic acid (\(\text{HCOOH}\)), a simple organic acid, releases hydrogen ions in solution, producing a sour taste. Thus, (A) matches with (II).
- (B) Bitter: Bitter taste is triggered by various alkaloids and organic compounds.
Quinine is a classic bitter alkaloid derived from cinchona bark, and is used as a standard reference compound for bitter taste evaluations. Thus, (B) matches with (IV).
- (C) Salty: Salty taste is elicited by monovalent cations, primarily sodium (\(\text{Na}^+\)).
Other alkali metal cations like lithium (\(\text{Li}^+\)) can also bind to salty taste receptors (such as ENaC channels), producing a similar salty taste. Thus, (C) matches with (I).
- (D) Sweet: Sweet taste is triggered by sugars, some amino acids, and artificial sweeteners containing specific chemical structures (like sulfonamide derivatives, such as saccharin and acesulfame potassium). Thus, (D) matches with (III).
Combining these pairs yields the sequence: (A) - (II), (B) - (IV), (C) - (I), (D) - (III).
This matches Option (A).
Step 3: Final Answer:
The correct matching sequence is (A)-(II), (B)-(IV), (C)-(I), (D)-(III), which corresponds to Option (A).