Q.Why did Gregor Mendel choose the garden pea (Pisum sativum) as his experimental organism for studying the inheritance of characters? Mention any three features of the plant that made it suitable.

Step 1. The garden pea normally self-pollinates because its reproductive organs are enclosed within the keel petals, which let Mendel first obtain pure-breeding (true-breeding) lines simply by repeated self-fertilisation.

Step 2. The very same flower structure could be manually overridden — Mendel emasculated a flower (removed its own anthers before maturity) and dusted its stigma with pollen from a chosen second plant, letting him perform controlled artificial cross-pollination whenever he wished.

Step 3. He studied seven characters, each showing exactly two sharply distinguishable, non-overlapping forms (e.g., tall/dwarf, round/wrinkled), which made scoring offspring unambiguous.

Step 4. The pea has a short generation time, produces many seeds per pod, and many pure varieties were already available from seed merchants — together giving Mendel the large numerical sample sizes his statistical, ratio-counting method required.

Identify which structural/biological features of the pea plant serve BOTH the need to maintain pure lines and the need to perform controlled crosses, plus the practical features enabling large-sample counting.

• Forgetting that the pea's self-pollinating flower structure is what allows BOTH maintaining pure lines AND controlled artificial crossing — students often mention only one of the two.
• Omitting the sharply contrasting, non-overlapping nature of the seven characters, which was essential to unambiguous scoring.