Which is a morphological variation

Analyze the question: "Morphological" refers to form, structure, or outward physical appearance. A morphological variation is a difference in an observable physical feature among individuals of the same species.

Concept: Types of variation in humans

• Morphological (structural) variation: differences in physical features such as height, skin colour, finger prints, and body shape. These can be seen or measured.
• Physiological variation: differences in how the body functions, such as the ability to taste PTC, the ability to roll the tongue, and blood group.
• Behavioural variation: differences in conduct or habits.

Going through the options:

• A. Ability to taste PTC: a physiological/biochemical trait (taster vs non-taster), not a physical structure.
• B. Ability to roll the tongue: this is often listed as a discontinuous variation. It is a functional ability rather than a structural form, so it is usually classed as physiological.
• C. Behaviour: this is behavioural variation, not morphological.
• D. Blood group: a physiological/biochemical variation (A, B, AB, O), not visible externally.
• E. Finger print: the pattern of ridges (loops, whorls, arches) is a visible structural feature of the skin. It is unique to each person and is a morphological variation.

Answer: E. Finger print.

Tip: Ask yourself, "Can I see and describe its physical shape or structure?" If yes, it is morphological (for example height, finger print, skin colour). If it involves a function, a chemical test, or an ability (tasting, tongue rolling, blood grouping), it is physiological.