Ability to taste PTC in some individuals is a character that is

Step 1: Analyze the question PTC (phenylthiocarbamide) is a chemical that tastes bitter to some people but is tasteless to others. The question asks what kind of character this ability is.

Step 2: Explain the concept

• Acquired characters are developed during a person's lifetime through environment, training or injury (e.g., a scar, or learning a skill). They are not passed to offspring.
• Heritable characters are controlled by genes and passed from parents to offspring.
• Sex-linked characters are controlled by genes on the sex chromosomes (e.g., colour blindness, haemophilia on the X chromosome).
• Morphological characters concern physical form or structure (e.g., height, shape of the ear lobe).

Step 3: Apply to PTC tasting The ability to taste PTC is controlled by a single gene (the TAS2R38 gene).

• The tasting allele (T) is dominant.
• The non-tasting allele (t) is recessive.

So tasters have the genotype TT or Tt, while non-tasters are tt. This is inherited from parents, so it is a heritable character. It is not learned or acquired during life.

It is also not sex-linked, because the gene is on an autosome (chromosome 7), so males and females are affected equally. It is not a morphological feature either, because it is a physiological or biochemical response, not a body structure.

Step 4: Answer The ability to taste PTC is a heritable character, so the answer is B.

Tip: PTC tasting is a classic example of a simple Mendelian trait in humans, along with the ability to roll the tongue and attached or free ear lobes. If a JAMB question mentions these traits, think "inherited, controlled by genes". Also remember that sex-linked traits show unequal frequency in males and females, and PTC does not.