The type of placentation found in tomato fruit is called

Analyze the question: Placentation is the way ovules are attached inside the ovary of a flower (and later the fruit). We need the type found in tomato.

Explain the concept: The main types of placentation are:

• Marginal: ovules attach along one edge of a single carpel (e.g., beans, peas, other legumes).
• Axile: ovules attach to a central axis in an ovary with two or more fused carpels and chambers (locules). Examples are tomato, hibiscus, orange and lily.
• Parietal: ovules attach to the ovary wall, with one chamber (e.g., pawpaw, cucumber).
• Free central: ovules attach to a central column in a single chamber, with no partitions (e.g., Dianthus, primrose).
• Basal: ovules attach at the base of the ovary (e.g., sunflower).
• "Bisal" in option B is most likely a misprint of "basal", which is not the answer anyway.

Solution:

1. A tomato fruit is formed from a syncarpous ovary (fused carpels).
2. If you cut a tomato across, you see two or more chambers (locules) divided by partitions.
3. The seeds are attached to the central core where the partitions meet. This central axis bearing the ovules is the signature of axile placentation.

Answer: The tomato has axile placentation, which is option A.

Tip: Cut a tomato across and you see the seeds in separate chambers around the middle. Remember "Axile = Axis in the centre with chambers around it." Also, hibiscus and tomato are the classic axile examples in Nigerian exams.