A botanist cuts the flowers of guava, plum and brinjal, one after the other…
Contributed by StemPy LabTry it on paper first. A hint, the key idea and the worked solution are here when you need them.
A botanist cuts the flowers of guava, plum and brinjal, one after the other. (a) Name the position of the ovary in each. (b) Which has an inferior ovary, and what has happened to its thalamus? (c) In which of the three do the other whorls arise above the ovary?
Need a reminder? The key ideaShow
A flower has the calyx, corolla, androecium and gynoecium. Bisexual or unisexual; actinomorphic, zygomorphic or asymmetric. Hypogynous (superior ovary), perigynous (half inferior), epigynous (inferior). Aestivation: valvate, twisted, imbricate, vexillary. Stamens: filament and bilobed anther with four pollen sacs; epipetalous, epiphyllous, monoadelphous, diadelphous, polyadelphous. Carpel: ovary, style, stigma; apocarpous or syncarpous. Placentation: marginal, axile, parietal, free central, basal.
The worked solution
Have you tried it?
Work it out on paper first. It is fine to get stuck or make a mistake: that is how we learn. When you are ready, go through the solution one step at a time, and check each step against your own.
Step 1. Guava. The thalamus grows up round the ovary and fuses with it. The other parts arise above. It is epigynous, with an inferior ovary.
Step 2. Plum. The ovary lies at the centre and the other parts on the rim of the thalamus, at nearly the same level. It is perigynous, with a half inferior ovary.
Step 3. Brinjal. The ovary is in the highest position, and the other parts are below it. It is hypogynous, with a superior ovary.
Answer: (a) guava epigynous, plum perigynous, brinjal hypogynous; (b) guava, whose thalamus has grown up round the ovary and fused with it; (c) guava.
Discussion (0)
Log in to join the discussion.
Loading…