What are Megaphyll leaves?
Microphylls are defined as leaves of small size, with simple venation (one vein) and associated with steles that lack leaf gaps (protosteles). By contrast, megaphylls are defined as leaves of generally larger size, with complex venation and associated with leaf gaps in the stele .
What plants have Megaphyll leaves?
Megaphylls are seen in ferns and more derived vascular plants. In addition to photosynthesis, leaves play another role in the life of the plants.
What does Megaphyll mean in biology?
/ (ˈmɛɡəfɪl) / noun. botany the relatively large type of leaf produced by ferns and seed plantsCompare microphyll.
What is a Megaphyll and from what did it evolve?
According to the telome theory, megaphylls evolved from the three-dimensional lateral branches of early vascular land plants in a hypothetical series of three transformations; first, the formation of determinate lateral branches (overtopping); second, the development of ‘flattened’ branch systems (planation); and third …
What is the function of the Megaphyll?
Generally, the main function of both microphylls and megaphylls is to undergo photosynthesis. In comparison, the main structural feature of megaphylls is the presence of multiple veins. Also, they contain leaf gaps.
Do mosses have Megaphyll leaves?
Club mosses differ from other vascular seedless plants due to the presence of microphylls, very small leaves that only have a single vein. Most other plants have megaphylls, leaves with more than one vein. Like all vascular plants, club mosses reproduce via alternation of generations.
When did Megaphyll leaves evolve?
Large megaphyll leaves became widespread some 40–50 Myr after the origination of vascular land plants. Fossil evidence indicates, however, that at least one group of plants was capable of producing megaphyll leaves millions of years earlier.
How do sporophylls differ from microphylls?
Sporophylls are present in both microphylls and megaphylls. In a plant, if the sporophyll bears megasporangia, they are called megasporophylls. If it bears microsporangia then it’s called microsporophylls. Sporophylls lead to the development of male and female gametophytes of seed plants (spermatophytes).
Is Megaphyll a sporophyte or gametophyte?
Both microphylls and megaphylls can be sporophylls. In heterosporous plants, sporophylls (whether they are microphylls or megaphylls) bear either megasporangia and thus are called megasporophylls, or microsporangia and are called microsporophylls.
How do you identify a lycophyte?
The distinguishing features of the lycophytes are the arrangement of their vascular tissues and their leaves—microphylls with only a single vascular strand. The sporangia on the modern plants are kidney-shaped, like those of the ancestral forms, and borne on sporophylls clustered in strobili.
What is enation theory?
enation theory The theory that accounts for the origin of the fern leaf by suggesting that it arose from the development of simple outgrowths (enations).
What is Medullated protostele?
A *protostele in which the central core of xylem consists mainly of tracheids interspersed with numerous parenchyma cells. It thus resembles the medulla (*pith ) of a *siphonostele (hence the name).
What is stili?
In a vascular plant, the stele is the central part of the root or stem containing the tissues derived from the procambium. These include vascular tissue, in some cases ground tissue (pith) and a pericycle, which, if present, defines the outermost boundary of the stele.
Is Megaphyll haploid or diploid?
megaspore [Gk. megas: large + spora: to sow] In plants, a haploid spore that produces a female gametophyte.
What makes a lycophyte a lycophyte?
Is Spike Moss lycophyte?
lycophyte, (class Lycopodiopsida), class of spore-bearing vascular plants comprising more than 1,200 extant species. Three lycophyte orders are recognized: the club mosses (Lycopodiales), the quillworts and their allies (Isoetales), and the spike mosses (Selaginellales).
What is Enation in plants?
: an outgrowth from the surface of an organ a plant virus causing enations on leaves.