apical placentation
Học thuậtThân thiện
Definition
Noun (Botany) A type of placentation in flowering plants where one or a small number of ovules are attached at the apex (the top) of a simple or compound ovary.
Usage
This is a specific botanical term used to describe the arrangement and attachment point of ovules within the ovary of a flower. It is a technical descriptor of plant morphology.
Examples
- In the family Ranunculaceae, many species exhibit apical placentation.
- The botanist identified the flower's structure, noting its apical placentation.
- Apical placentation is less common than other types, such as parietal or axile placentation.
Advanced Usage
- The term is primarily used in scientific descriptions, taxonomic keys, and botanical literature.
- It can be contrasted with other placentation types: (at the base), (on the ovary wall), (on the central axis), and (on a central column).
Variants and Related Words
- Placentation (n): The general term for the arrangement of ovules within the ovary.
- Apical (adj): Relating to or located at the apex or tip.
- Ovule (n): The structure that develops into a seed after fertilization.
- Ovary (n): The part of the pistil that contains the ovules.
Synonyms
- Terminal placentation (This is a less common but acceptable synonym in botanical contexts.)
Related Phrases/Concepts
- Simple ovary: An ovary formed from a single carpel.
- Compound ovary: An ovary formed from two or more fused carpels.
- Gynoecium: The female reproductive part of a flower, consisting of one or more pistils.
Noun
- where one or few ovules develop at the top of a simple or compound ovary