"Sessile" describes something that is attached or fixed in place, lacking a stalk or the ability to move freely. The term has different applications depending on the context.
Sessile in Botany
In botany, sessile refers to:
- Flowers and leaves: These are considered sessile when they grow directly from the stem, without having a stalk (also known as a petiole or peduncle). The reference specifies: "(of flowers or leaves) having no stalk; growing directly from the stem."
Sessile in Zoology
In zoology, sessile describes:
- Animals: Some animals are permanently attached to a surface or substratum. These animals cannot move around freely after their larval stage. For example, barnacles are sessile. The reference states: "(of animals such as the barnacle) permanently attached to a substratum."
| Feature | Botany | Zoology |
|---|---|---|
| Definition | Lacking a stalk; growing directly from stem | Permanently attached to a surface/substratum |
| Examples | Certain flowers, leaves | Barnacles, sponges, corals |
| Mobility | Immobile at point of attachment | Immobile after attachment (usually post-larval) |
In summary, "sessile" means attached or fixed. In botany it refers to plant parts, whereas in zoology it generally refers to animals attached to a surface and lacking the ability to move independently.
