Ephedra-General Characters,Distribution,Thallus and Reproduction |something new

Ephedra-General Characters,Distribution,Thallus and Reproduction |something new

• Kingdom- Plantae
• Division- Gymnospermophyta
• Order –Epheriadales
• Family –Epherideacae
• Genus - Ephedra

Ephedra is that the solely genus in {family ephedraceae|Ephedraceae|family |gymnosperm family} and order Ephedrales. it's diagrammatical by fifty species.

Ephedra

8 Species is Found in Republic of India that is distributed within the region of Haryana,Punjab,Rajasthan and a few a part of Kasmir.

Morphological options of Ephedra:

The plant body is sporophytic and shows xeric characters. 

Ephedra Morphology

principally the plants area unit woody shrubs and its wood kind is picnoxylic  ( means that show hardness and economical necessary )a only a few species area unit lianas(Cimbing on different tree ) and a few species grow into atiny low tree. E. compacta reaches thirty cm tall E. triandra could be a tree.

Root:-

In this genus of Gymnosperms it's no protoctist zone or mycorrhiza. there's a outstanding underground faucet system. soon the accidental roots develop.

Stem:-

 It shows Equistem like look and its stem is additionally feels like stem of eqiustem . 

It shows Phylloclode kind modification means that Stem show chemical change . 

The Branches is additionally inexperienced at node and segment . 

The branching starts early at the cotyledonary stage. 

The top plant tissue has well marked membrane layer however the expansion of segment is freelance because of the presence of the meristemetic zone at its base.

 This zone dries up at the top of every season. It leads to the breakableness and shedding of the branches

Leaves:

Leaves area unit snall scaly gift at the node position and also the variety of leaves rely upon the amount of Ridges and grooves as same in equistem .

 every leaf contains 2 branchless, parallel veins. they're thus minute that they're of no use i. e., unable to perform chemical change. 

The perform of chemical change is carried by inexperienced stem. within the angle of every leaf is gift a bud for the branch. True foliage leaves area unit absent.

Internal Structures of Ephedra: 

Stem at node Region Internal Structure :-

T.S. of Stem

Epidermis :-

 it's the outmost layer of thick walled cells, lined with a thick layer of cuticle. 

Sunken stomata area unit gift on the slopes of the ridges within the circular pits.

The kind of stomata is sunken type because of xeric character of genus ,so rate of transpiration is decrease in sunken stomata.

Hypodermis:-

 it's gift just under the ridges. it's created of sclerenchymatous cells and provides mechanical strength to the plant and hardness of wood

 Beacause in contain polymer covering over their surface.

Cortex :-

                 In is gift between the thick walled sclerenchyma and vascular  cylinder. It are often differentiated into outer and inner cortex. 

The outer cortex contains 2-3 layers of radially elongated palisade tissue and inner cortex consists of 2-3 layers of spongy parenchyma. 

The cells of outer and inner cortex area unit loosely organized with giant animate thing areas and area unit given chlorophyl to perform the perform of chemical change.

 a couple of patches of scleranchymatous cells might also occur within the cortex to supply mechanical support to the young axis.

Endodermis :-

 it's the innermost layer of cortex. it's not simply distinguishable from the plant tissue cells.

Pericycle :

It is gift below the endodermis. it's single stratified  and sick outlined.

Vascular System :-

 it's endarch, siphonostele and consists of the many vascular  bundles organized in a very ring. vascular  bundles area unit conjointed, collateral, open and endarch. 

the amount of primary vascular  strands is mostly eight, out of that four tiny represent the foliar traces whereas the opposite giant four area unit stem bundles.

Foliar traces run upto the node. vascular tissue consists of tracheids, vessels and vascular tissue parenchyma.

 because of the presence of the vessels the shrub resembles angiosperms. The bast consists of sieve cells, bast parenchyma and simple protein cells.

 bast and vascular tissue area unit separated by a slender strip of cambium.

Medullary Ray :-

Broad, parenchymatous medullary rays area unit gift in between the vascular  bundles. Medullary rays connect the pith with cortex.

It is gift within the centre. it's created up off skinny walled parenchymatous cells.

 close to the node its cells become powerfully woody forming a peridermal diaphragm that accounts for the fast separation of the branches within the region

Secondary Growth :-

The secondary growth takes place by the activity of intrafascicular cambium and interfascicular cambium.

Mature Stem

 once forming an entire ring of cambium, the vascular tissue cells cut of secondary bast on the outer facet and secondary vascular tissue towards the inner facet.

Due to formation of the secondary tissues, primary bast is crushed and also the primary vascular tissue is pushed towards the inner facet at the bottom of the secondary vascular tissue.

 additionally to plant tissue cambium additionally forms medullary rays (secondary). These rays area unit long, broad (multiseriate) and traverse between secondary vascular tissue and secondary bast.

Radial Longitudinal Section :-

xylem tracheids, vessels and medullary rays area unit clearly visible.

 Medullary rays area unit cut lengthwise and their length and height area unit unconcealed .

every vascular ray consists of on an irregular basis distributed ray cells and ray tracheids. Tracheids possess seagirt pits on their radial and tangential walls.

 In vessels, the seagirt pits are organized within the same method as tracheids.

Tangantial Longitudinal Section :-

Like R.L.S. in T.L.S. also, the xylem, tracheids, vessels and medullary rays area unit clearly visible however they're cut transversally here.

 (Bordered pits and straightforward pits area unit seen on the radial and tangential walls. 

The medullary rays area unit elongated and on their tangential walls area unit gift easy pits.

Leaf:

The transversal section of scaly leaf is oval in form and may be differentiated into cuticle, mesophyll tissue and plant tissue.

T.S. of Leaf

Epidermis :-

It is outer most single layer of thick walled elongated cells.

The cells area unit lined with thick cuticle. Sunken stomata area unit gift .

Mesophyll tissue:

Two or 3 layers of palisade tissue area unit gift inner to cuticle. 

The cells area unit crammed with plastid and huge animate thing areas area unit gift between them.

 within the centre of the leaf parenchymatous tissue is gift.

Vascular tissue:

Two vascular  bundles area unit embedded within the parenchymatous tissue. The vascular  bundles area unit collateral and closed. vascular tissue is gift towards the side.

Root:

The transversal section of root shows single layer epiblema, outer cortex (composed of collenchymatous cells), inner cortex (composed of parenchymatous cells) endodermis and pericycle.

 vascular  bundles area unit radial and exarch. the basis could also be diarch or triarch.

Reproduction in Ephedra:

Ephedra is monogenesis (produces 2 kinds of spores: microspores and macrospores) and dioecian (both these kinds of spores area unit made on 2 totally different plants of identical species.

 E. fuliata is autoicous. Microspores area unit shaped in male flowers whereas megaspores area unit shaped in feminine flowers.

These flowers area unit gift within the variety of cone like compound strobili. 

Male flowers area unit gift within the variety of male reproductive structure whereas feminine flowers area unit gift within the variety of female reproductive structure. 

each male and feminine strobili area unit compound i. e.,the cone axis bears pairs of bracts that be either microsproangiate or release shoots.

Male reproductive structure (Staminate Strobilus):

Male strobili arise in clusters from the nodes of the branches. every reproductive structure is rounded, ovoid or spherical in form and arises within the axis of a leafage. 

Male Reproductive part

Their variety at the node depends upon the amount of scale leaves.

Each reproductive structure incorporates a central axis that bears 2-12 pairs decussately organized easy, broad and cupped bracts.

 Lower most 1-2 pairs of bracts area unit sterile. within the angle of every fertile husk arises a male flower or male flower .

 A male reproductive structure with many male flowers are often compared with AN inflorescence.

Male flowers:

Each male flower has 2 bilabiate skinny bractioles (perianth) that encloses a reproductive structure. 

Bracteoles area unit united at the bottom. 

The flower incorporates a short stalk called microsporangiophore and 2, eight to 12 microsporangia at its tip .

Microsporangia area unit sessile and erupt terminally. Male flower is additionally known as easy reproductive structure.

 A compound male reproductive structure, therefore, consists of the many such strobili.

Development of microsporangium:

The development of spore case is eusporangiate.

Development in Microspore

Microspangia arise at the tip of microsporangiophore.

The microsporangiophore arises as tiny protuberance within the angle of the fertile husk of male reproductive structure.

The apex of microsporangiophore becomes compound once growing for a few time.

Each lobe represents a spore case.

Few layer cells in every lobe enlarge in size.

These cells consist giant nuclei, denser cytoplasts and area unit called cell cells.

These cells divide periclinally into outer primary wall cells or primary membrane bone cells and first reproductive structure cells .

Primary reproductive structure cells any divide by 2 periclinal divisions to differentiate middle wall layer, inner tapetal layer and reproductive structure cells.

The primary wall cells perform directly because the outer wall of the spore case.

According to some staff, the first wall cells divide periclinally to create 3 stratified  thick wall.

The reproductive structure cells divide any to create sizable amount of spore mother cells.

 every spore cell divides by meiosis to create four haploid microspores organized in a very linear foursome.

Structure of spore grain:-

Pollen grain is that the initial cell of the male flora. every spore grain is elliptical, cell organ and has 2 wall layers. 

The outer wall layer is thick and is named exine whereas the inner male layer is then and is named intine.

 (Ovulate Strobilus) or female  Cone:-

They usually arise in pairs at every node within the angle of scale leaves.

Female Cone

A feminine reproductive structure seems to be AN elliptical structure with a pointed apex .

It retains identical compound structure because the male reproductive structure. It consists of a brief axis to that area unit hooked up 3 or four pairs of decussate bracts.

In E. artefact these bracts area unit swollen and juicy .

All the trys of bracts area unit sterile except the topmost one that bears a pair of ovules in its angle and should be multifariously colored.

 Out of the pairs of the ovules only 1 survives and it takes up a false terminal position.

Structure of ovule (megasporangium):

Longitudinal section of AN ovule shows that it consists of a mass of parenchymatous cells within the centre. it's known as plant structure.

 The plant structure is encircled by a two-layered envelope. 

These area unit typically selected as outer and inner integuments. 

The outer envelope is made by four segments and receives four bundles whereas the inner one is made of 2 segments and receives 2 bundles.

The lower half the inner envelope is coalesced to the plant structure however higher is free and prolongs into a protracted aperture tube. 

By the time of fecundation just under the aperture spore chamber develops. spore chamber in shrub is that the deepest illustrious among the Gymnosperms.

 the ground of the spore chamber is made by feminine gametophytic tissue and not by the plant structure as in different gymnosperms.

Development of Ovule:

Development of the ovule takes place within the variety of a tiny low cellular protuberance.

 This protuberance will increase in size and becomes the plant structure. 

shortly neighbour cells of the bottom forms inner and outer integuments. Inner natural covering surrounds the plant structure except the highest wherever it type atiny low gap known as aperture.

Ephedra-General Characters,Distribution,Thallus and Reproduction 

Ephedra-General Characters,Distribution,Thallus and Reproduction 

Ephedra-General Characters,Distribution,Thallus and Reproduction

 Ephedra-General Characters,Distribution,Thallus and Reproduction 

A layer cell cell differentiates within the plant structure. It divides periclinally into outer membrane bone cell and inner spore cell. The latter is pushed quite deep into the nucellar tissue.

The spore cell divides meiotically to create four hapliod megaspores. usually the bottommost spore (towards the chalazal end) remains purposeful. 

It enlarges and provides rise to feminine flora (first cell of the feminine gametophyte) and also the remaining higher 3 megaspores degenerate.

Ephedra-General Characters,Distribution,Thallus and Reproduction Ephedra-General Characters,Distribution,Thallus and Reproduction 

Ephedra-General Characters,Distribution,Thallus and Reproduction 

Ephedra-General Characters,Distribution,Thallus and Reproduction

 Ephedra-General Characters,Distribution,Thallus and Reproduction 

Ephedra-General Characters,Distribution,Thallus and Reproduction 

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