Search results
Results from the WOW.Com Content Network
At that time, the elaters uncoil to extend out from the spore and will catch air currents. The fact that they are extended only when conditions are dry means that successful spore dispersal is more likely. The mature strobili of a horsetail (Equisetum arvense). A cross section through a horsetail strobilus, showing spores with elaters.
The spores are dispersed through a catapult-like system, flinging the spores out briefly at up to 10m/s. This is caused by the gradual build up of a high negative pressure (200-300 atmospheres) within annulus cells from water loss. [1] As these cells lose water, they shrink, and are designed to inwardly bend on the outer face of the annulus.
The capsule of the sporophyte is inclined, curved, bilaterally symmetric and about 1.5 mm. [4] As for the calyptra, it is cucullate, smooth and about 2.5 mm. [4] The spores are about 3-22 μm. [4] Since it is a member of the Bryopsida class it also has arthrodontous peristome teeth which aid in spore dispersal. Fissidens adianthoides have 16 ...
The sporophyte produces spores (hence the name) by meiosis, a process also known as "reduction division" that reduces the number of chromosomes in each spore mother cell by half. The resulting meiospores develop into a gametophyte. Both the spores and the resulting gametophyte are haploid, meaning they only have one set of chromosomes.
Elaters—structures that form inside a sporangium and aid in spore dispersal of horsetails, liverworts, and hornworts; Loment—a type of fruit that breaks apart but is not dehiscent; Schizocarp—a type of fruit that breaks apart and may or may not be dehiscent.
A diaspore of seed plus elaiosome is a common adaptation to seed dispersal by ants (myrmecochory). This is most notable in Australian and South African sclerophyll plant communities. [1] Typically, ants carry the diaspore to their nest, where they may eat the elaiosome and discard the seed, and the seed may subsequently germinate.
The bryophytes consist of about 20,000 plant species. [5] [6] Bryophytes produce enclosed reproductive structures (gametangia and sporangia), but they do not produce flowers or seeds. They reproduce sexually by spores and asexually by fragmentation or the production of gemmae. [7]
Dispersal is also used to describe the movement of propagules such as seeds and spores. Technically, dispersal is defined as any movement that has the potential to lead to gene flow. [1] The act of dispersal involves three phases: departure, transfer, and settlement. There are different fitness costs and benefits associated with each of these ...