Search results
Results from the WOW.Com Content Network
Thallus (pl.: thalli), from Latinized Greek θαλλός (thallos), meaning "a green shoot" or "twig", is the vegetative tissue of some organisms in diverse groups such as algae, fungi, some liverworts, lichens, and the Myxogastria.
In lichens it refers to the region of the thallus that is free of algae. The prothallus develops from a germinating spore. It is a short-lived and inconspicuous heart-shaped structure typically 2–5 millimeters wide, with a number of rhizoids (root-like hairs) growing underneath, and the sex organs: archegonium (female) and antheridium (male ...
The vegetative structure of Conocephalum is a thallus which has the appearance of a flattened body of plant tissue. [5] [22] The thallus is irregularly branched [4] and relatively large, reaching lengths of roughly 20-24 cm. [4] [5] In contrast to C. conicum and C. salebrosum, the thallus of C. supradecompositum is relatively small, measuring 2 ...
Lichens are grouped by thallus type, since the thallus is usually the most visually prominent part of the lichen. Thallus growth forms typically correspond to a few basic internal structure types. Common names for lichens often come from a growth form or color that is typical of a lichen genus. Common groupings of lichen thallus growth forms are:
A byssoid lichen has a wispy, cottony or teased wool appearance due to the loosely woven hyphae in its thallus. [13] It has no outer cortex. [14] Lichens with this growth type can be split into two types. In one type, the thallus is dominated by fungal hyphae, with a photobiont – typically a coccoid green alga – sprinkled throughout. In the ...
Marchantia is a genus of liverworts in the family Marchantiaceae and the order Marchantiales.The genus was named by French botanist Jean Marchant after his father.. The thallus of Marchantia shows differentiation into two layers: an upper photosynthetic layer with a well-defined upper epidermis with pores and a lower storage layer.
The thallus contains specialised sclerotic cells in its ventral region that serve as conducting tissue, though these differ from true tracheids in both form and function. These sclerotic cells are elongated, thick-walled, dark brown, fibre-like cells with pointed ends that typically occur singly, though occasionally two or three may be found ...
The lamina or blade in macroscopic algae, like seaweed, is a generally flattened structure that typically forms the principal bulk of the thallus. [1] It is often developed into specialised organs such as flotation bladders and reproductive organs. [citation needed]