What Is Peristome In Botany?

What does Calyptra mean?

In bryophytes, the calyptra (plural calyptrae) is an enlarged archegonial venter that protects the capsule containing the embryonic sporophyte.

The calyptra is usually lost before the spores are released from the capsule.

The shape of the calyptra can be used for identification purposes..

How are spores spread?

Being so small and lightweight, spores can easily move unseen in the air currents, and most fungal spores are spread by the wind. … Many fungi need two of these colonies to grow next to each other and to mate before that fungus is able to form any new spores and so spread further.

How do Peristome teeth move?

Peristome teeth move backward and forward in response to changes in humidity assisting in spore release from the capsule. Plagiomnium novae-zealandiae -When humidity is high, the peristome teeth more inward and close over the capsule mouth.

Which is not a part of moss capsule?

Within the capsule, spore-producing cells undergo meiosis to form haploid spores, upon which the cycle can start again. The mouth of the capsule is usually ringed by a set of teeth called peristome. Protonema is formed after germination of moss capsule spores and is not a part of the capsule.

What is the function of Peristome teeth?

In pitcher plants, the peristome is a reflexed ring (or partial ring) of tissue that surrounds the entrance to the digestive tube in these plants. It often (for example in Cephalotus and Nepenthes) possesses sharp, overhanging ‘teeth’ which aid in prey retention.

What is the moss life cycle?

The life cycle of a moss, like all plants, is characterized by an alternation of generations. A diploid generation, called the sporophyte, follows a haploid generation, called the gametophyte, which is in turn followed by the next sporophyte generation.

Does the Protonema contain any structures?

Moss spores germinate to form an algae-like filamentous structure called the protonema. … These give rise to gametophores, stems and leaf like structures (bryophytes do not have true leaves (megaphyll). Protonema are characteristic of all mosses and some liverworts but are absent from hornworts.

What does the Archegonium produce?

An archegonium (pl: archegonia), from the ancient Greek ἀρχή (“beginning”) and γόνος (“offspring”), is a multicellular structure or organ of the gametophyte phase of certain plants, producing and containing the ovum or female gamete. The corresponding male organ is called the antheridium.

What did the Calyptra develop from?

(botany) In bryophytes, a thin, hood-like tissue that forms from the archegonium and covers the developing sporophyte.

How do Peristome teeth affect spore dispersal?

At maturity the spore capsule sheds the operculum. In dry conditions the capsule walls shrink, forcing the peristome teeth to bend back so as to finish up turned down against the outside wall of the spore capsule. At the same time the shrinkage of the capsule leads to the columella extending beyond the capsule mouth.

What do Elaters do?

Elaters are the ribbon or tube like structures attached to the wall of spore. The elaters function is to increase dispersal because they push the spores out of the plant by absorbing moisture.

What is the ploidy level of the Calyptra?

The diploid sporophyte (2n) is surrounded by the enlarged archegonium called the calyptra and is dependent on the haploid tissue of the archegoniophore for nutrients and water.