bipinnate leaf
Học thuậtThân thiện
Definition
Noun: A bipinnate leaf is a compound leaf where the primary leaf axis (the rachis) bears secondary axes (pinnae), and leaflets (pinnules) are arranged along these secondary axes. In other words, it is a leaf that is twice pinnate; the leaf structure branches twice.
Usage
This is a specific botanical term used to describe the morphology or shape of a leaf. It is used in scientific, horticultural, and botanical contexts.
Examples
- The leaf of the Albizia julibrissin (mimosa tree) is a classic example of a bipinnate leaf.
- Under the microscope, the botanist identified the specimen by its bipinnate leaf structure.
- Many ferns have bipinnate leaves, which gives them a very fine, lacy appearance.
Advanced Usage
- The term is often used in dichotomous keys for plant identification, where the presence of a bipinnate leaf is a distinguishing characteristic.
- It can be modified to describe the degree of division, e.g., "bipinnatifid" (twice pinnately cleft) or "tripinnate" (thrice pinnate).
Variants and Related Words
- Pinnate leaf (noun): A compound leaf with leaflets arranged on either side of a central axis, like a feather. A bipinnate leaf is a further division of a pinnate structure.
- Tripinnate leaf (noun): A leaf that is divided three times in a pinnate manner.
- Bipinnately (adverb): Describing an arrangement in a bipinnate manner. (e.g., The leaflets are arranged bipinnately).
Synonyms
- Twice-pinnate leaf
Different Meanings
This term has a single, precise meaning in botany. It does not have idiomatic or non-literal uses.
Noun
- a leaf having pinnate leaflets; as ferns