Which of the following best describes physiological variation in biology?

Step 1: Analyze the question The question asks which option best describes physiological variation. The key word is "physiological," which relates to how the body functions.

Step 2: Explain the concept Variation means the differences between individuals of the same species. It is commonly grouped into:

• Morphological (structural) variation: differences in physical form, such as height, skin colour, and body size.
• Physiological variation: differences in how body processes work, such as blood group, rate of metabolism, ability to taste PTC, and tolerance to heat or disease.
• Genetic variation: differences in genes (the underlying cause of much variation).
• Behavioural variation: differences in how organisms act.

Step 3: Evaluate each option

• A. Variations in physiological processes and functions of organisms. This matches the definition exactly.
• B. Differences in physical characteristics and appearance. This is morphological variation, not physiological.
• C. Differences in behaviour and social interactions. This is behavioural variation.
• D. Variations in genetic makeup. This is genetic variation.

Step 4: Answer

Exam tip: Match the prefix to the meaning. "Morpho-" means form or shape, "physio-" means function or processes, and "genetic" means genes. Examples of physiological variation that often appear in JAMB are blood groups (A, B, AB, O), the ability to roll the tongue, and the ability to taste PTC.