What is peristome in plants?

noun. Botany. the one or two circles of small, pointed, toothlike appendages around the orifice of a capsule or urn of mosses, appearing when the lid is removed. Zoology. any of various structures or sets of parts that surround or form the walls of a mouth or mouthlike opening.

What is the role of peristome?

In mosses, the peristome is a specialized structure in the sporangium that allows for gradual spore discharge, instead of releasing them all at once. Most mosses produce a capsule with a lid (the operculum) which falls off when the spores inside are mature and thus ready to be dispersed.

What do you mean by peristome?

Definition of peristome 1 : the fringe of teeth surrounding the orifice of a moss capsule. 2 : the region around the mouth in various invertebrates.

What is peristome formula?

Peristome of. Encalyptaceae is characterized by thick inner peristomial layer (IPL), so up to the late stages of its. development its cells do not divide, maintaining basic peristomial formula 4:2:2 (omitting preperistomial. layers).

What are Pseudoelaters?

In Hornworts, pseudo-elaters are tiny, filamentous structures that superficially resemble the spiralled elaters that are a feature of the capsules in many liverwort species. These pseudo-elaters do not spiral in the genera Anthoceros and help in spore release.

What is the function of the peristome teeth found on the capsule?

1. A ring of toothlike structures around the opening of a moss capsule. The teeth tend to bend and twist in dry weather, so opening the mouth of the capsule and allowing the spores to escape.

What is the function of Columella?

The columella is a sterile dome-shaped structure on the tip of a sporangiophore, its function is to allow for nutrient exchange between the active protoplasm below and the developing spores inside the upper part of the sporangial head.

What is peristome teeth where it is found?

The peristome is a fringe of teeth-like projections found at the mouth of the capsule.

What is Calyptra plant?

Definition of calyptra : a hoodlike structure in a plant especially : haploid tissue forming a membranous hood over the capsule in a moss.

What are Pseudoelaters and their functions?

Answer: Hornworts are a very unusual group of plants. As the sporophyte grows longer, it splits into two halves lengthwise, releasing the spores as they mature. Along with the spores are cells called pseudoelaters, which change shape as they dry out and thereby assist in scattering the spores.

What is Amphigastria?

: one of the small appressed stipulelike leaves on the ventral side of the stem in certain liverworts — compare jungermanniales.