Definition

Noun (Botany): A specific arrangement of ovules within a compound ovary, where the ovules are borne on thin, plate-like or ridge-like extensions (lamellae) that project from the placentae into the central cavity of the ovary.

Usage

This is a highly specialized botanical term used to describe the internal structure of certain fruits and flowers. It is primarily used in scientific descriptions, taxonomic keys, and academic texts related to plant morphology and reproduction.

Examples

• The genus (poppies) is characterized by lamellate placentation.
• Botanists identified the species by examining the lamellate placentation visible in the cross-section of the ovary.
• In contrast to parietal placentation, lamellate placentation features projecting partitions.

Advanced Usage

• The term is often used in comparative morphology to differentiate plant families. For example, "The presence of lamellate placentation helps distinguish this family from closely related ones that exhibit axile placentation."

Variants and Related Words

• Placentation (n): The general arrangement of ovules within the ovary. Lamellate placentation is one specific type.
• Lamella (n): A thin plate, layer, or membrane. This is the structural element from which the term is derived.
• Lamellar (adj): Having a structure of thin plates or layers.

Synonyms

• Septate placentation (in some specific botanical contexts, though nuances may exist).
• Projecting placentation (a more descriptive, non-technical synonym).

Different Meanings

This term has only one specific meaning within the field of botany. It does not have common idiomatic or figurative uses.

Notes

• Lamellate placentation is a subtype of parietal placentation, where the ovules are attached to the ovary wall. The "lamellate" specification indicates that the placentae form projecting partitions rather than being simple ridges on the wall.
• This structure is a key diagnostic feature for the identification of certain plant taxa.

Noun

1. with ovules on thin extensions of the placentae into a compound ovary