Read Placentation by Ovule Position
A focused NSEB read for locating ovules inside the ovary and matching the pattern to plant examples.
Living-system questions are solved by matching a structure or organism to its function, process and stated condition.
Trace where the ovules attach
Parietal placentation places ovules on the inner ovary wall of a unilocular ovary; axile placentation places them on a central axis in a multilocular ovary; marginal placentation runs along the ventral suture of a single carpel; and free-central placentation places them on a central column without septa.
Use examples as a cross-check
Dianthus and Primrose show free-central placentation. Pea and bean show marginal placentation; citrus and lily have axile placentation. In the linked three-diagram item, A is parietal, B axile, and C marginal, making four of the five statements true.
OlympIQ exam lens
- ✓Is the ovary unilocular or multilocular?
- ✓Are ovules attached to a wall, a central axis, a free column, or a ventral suture?
First identify the attachment position in the diagram, then use the named example to check your choice.
Ready to try the pattern?
100% coverage across the 2 linked questions.
Practise 2 linked questions