The leaves are microphyllous, lanceolate to ovate and mostly arranged in an anisophyllous opposite order though in some species the arrangement may look spiral. Draw a neatly labeled diagram of chloroplast found in leaf, and its role in photosynthesis? Receptacle is globose to elongate with short to moderately long paraphyses, indusium hemitelioid to sphaeropteroid. The sporangia are developed in strobilis, which are terminal and slender. PDF Topic 22. Introduction to Vascular Plants: The Lycophytes TOS4. The plant body bears long-creeping rhizomatous stem bearing scales and few to many, usually long, fibrous roots. Below the endodermis is present a single-layered pericycle. The entire plant is 10 50 cm. Each sorus is rounded and borne on the veins on the under surface, often at a fork. 2. Oxford University Press is a department of the University of Oxford. of mature stem shows a number of tissue zones, viz. b) External to the cortex, there are conspicuous leaf base parts, which are, of course, parenchymatous. Sporangia are terminal. What is a trophic hormone? Stem protostelic; leaves borne in a close spiral, more or less acicular; sporangia very large, sessile and trabeculated. Psilotum 2. Leaves monomorphic, indusium superior, lamina entire. Strobilus - Wikipedia Advertisement cookies are used to provide visitors with relevant ads and marketing campaigns. There are four rows of leaves two rows of smaller leaves (median leaves) on the upper side and two rows of larger leaves (lateral leaves) on the lower side, there being one large and one small leaf at each node. Cortex is broad, homogeneous throughout or divided into three concentric zones, i.e., outer and inner zones of elongated sclerenchymatous cells and middle zone of large thin-walled parenchymatous cells. Leaves alternate, bilobed, long; sporocarp dimorphic. Just below each groove is present a large air canal in the parenchymatous cortex. Pollen strobili of Pinophyta are similar to those of cycads (although much smaller) and Ginkgoes in that they are composed of microsporophylls with microsporangia on the abaxial surface. Anatomy of Equisetum (With Diagram) | Pteridophyta, Structure of Lycopodium (With Diagram) | Pteridophyta, Anatomy of Funaria (With Diagram) | Bryophyta. Why do you think that carbohydrates are not digested in the stomach? Leaves are microphyllous and spirally arranged. It currently publishes more than 6,000 new publications a year, has offices in around fifty countries, and employs more than 5,500 people worldwide. A T.S. This website includes study notes, research papers, essays, articles and other allied information submitted by visitors like YOU. The cookie is used to store the user consent for the cookies in the category "Performance". Strobilopterus - Wikipedia It has an erect, branched aerial part and a horizontal rhizomatous part with adventitious roots and tubers at the nodes. Similarly the small spores are microspores formed in microsporangium borne on a microsporophyll. Sori elongate to long, borne on a vein, covered by a short to very long indusium; sporangia long stalked, annulus interrupted by the stalk, homosporous. The structure is exactly similar with that of aerial sterile shoot, except a few following minor differences: 2. It is conspicuous only at the inter-nodal zone. Liquid-preserved strobili of Lycopodium, showing reniform sporangia through translucent sporophylls, Micrograph of the strobilus of Lycopodium sp., showing spores borne in sporangia, Liquid-preserved strobili of Selaginella, showing mega- and microsporangia through translucent sporophylls. Sporangia are borne in the axil of some leaves and there are distinct sterile (vegetative leaves) and fertile (sporophylls) patches on the stem. The epidermis gives rise to many root hairs. Sporangia borne in roundish to elongate linear, abaxial sori, or rarely also on the leaf tissue, indusiate, indusium reniform, sporangia stalked, annulus vertical. Adventitious, branched roots develop in clusters from below the nodes. A few sporangia are aggregated together to form sorus. Sporangia are aggregated to form strobilus. 7. 7. Phlegmarius phlegmaria (L) Sen & Sen (Lycopodium phlegmaria L.): Plants are dichotomously branched, pendent, epiphytic herbs. Size of the sporophyte ranges from few centimetres to several feet in different species. 6.3.1: Lycopodiopsida - Biology LibreTexts Sporangia are aggregated into a lax strobilus at the terminal parts of the aerial branches. Habit and Habitat of Lycopodium: Lycopodium is commonly known as 'club moss' due to their moss like appearance and club shaped strobili. of stem shows central protostelic to siphonostelic core surrounded by cortex. Performance cookies are used to understand and analyze the key performance indexes of the website which helps in delivering a better user experience for the visitors. of root shows a monarch protostele on one side of a central air space; xylem and phloem are almost collateral. In 1.s. in the Pteridophyta, in order that those facts may have their due weight in the general discussion of the balance of the vegetative and fertile regions of the primitive leafy sporo- . 11. 208). 237). et Vasco. Sporangia are aggregated together forming coenosori. Yeast: Origin, Reproduction, Life Cycle and Growth Requirements | Industrial Microbiology, How is Bread Made Step by Step? This cookie is set by GDPR Cookie Consent plugin. The single living member of the Ginkgophyta, Ginkgo biloba produces pollen strobili, but the ovules are typically borne in pairs at the end of a stem, not in a strobilus. It is formed by the compactly arranged sporophylls on the terminal parts of the aerial branches. Origin & Evolution of Pteridophytes (Vascular Cryptogams) - Wandofknowledge ): It is a small, erect, rooted and dichotomously branched, herbaceous plant. T.S. Leaves are monomorphic megaphyllous and borne in a cluster. 11. 228 A). [2] The carapace of Strobilopterus was wide and semicircular in shape, with the lateral eyes lunate to crescentic with the palpebral lobe between the central and centrimesial sectors. It is homosporous, globose, trilete and ridged. (Lycopodium cernuum L): It is small and somewhat prostrate herb and about 45 90 cm long. These cookies help provide information on metrics the number of visitors, bounce rate, traffic source, etc. According to some it is the uppermost whorl of sterile leaves while others are of the opinion that it is the lowermost sterile sporangiophore (Fig. Content Filtration 6. The plant is herbaceous with copiously branching stem, the ultimate divisions usually flabellately dichotomous, trailing, sub-erect or scandent. ex. But opting out of some of these cookies may affect your browsing experience. What do you mean by permeability of membrane? Sporangia are grouped together as sori. Several microphyllous leaves fused together and form a sheath around stem at node, Strobili terminal and consists only of whorled sporangiophores, homosporous. Share Your PDF File Let us know if you have suggestions to improve this article (requires login). Our editors will review what youve submitted and determine whether to revise the article. 21. Welcome to BiologyDiscussion! Privacy Policy3. Morphologically the cone scale is a reduced stem. Lamina entire sori 1-2 nerved, laterally elongated, indusiate. Spores homosporous, trilete, sori indusiate, marginal; leaf dimorphic. Copyright 10. Phloem is present in between two strands of metaxylem and made up of phloem parenchyma and sieve tubes. Pteridophytes: Origin, Classification and Importance | Botany Branches are devoid of hairs, and do not curl up when dry. A T.S. The branches curl up when dry. Plants homosporous, leaf 1-2 pinnate, sporangia in sori on the ventral side of the leaf, sporangia with indusium, sporangial development mixed. Pollen cone of Ephedra showing microsporangia. The lateral organs of seed strobili are megasporophylls (modified leaves) that bear two to several marginal ovules. A T.S. 10. Our mission is to provide an online platform to help students to share notes in Biology. The plant body has a short, vertical, subterranean rhizome. There are oval, bean-shaped rounded to squarish and usually formed in a cluster of a few to many; A longitudinal horizontal section of the sporocarp cuts each sorus transversely and it is seen that each sorus is elongate, covered by a delicate indusium, gradade basipetal in arrangement with a row of larger sporangia (mega-sporangia) on top and two rows of smaller sporangia (microsporangia) on two sides. The xylem consists of protoxylem and metaxylem with the former being exarch and consisting of spiral or annular tracheids, and the latter consisting of scalariform tracheids. Pteris 18. By clicking Accept, you consent to the use of ALL the cookies. The gross morphology of plant body in some Indian species (Fig 6.3) is discussed below: The plant has a weak, prostrate stem trailing along the surface and with adventitious roots growing from anywhere on the lower surface. There is a clear endodermis outside the stele. Annals of Botany Sori are non-paraphysate and covered by an abaxial indusium. Study the strobilus, arrangement of sporangia, L.S. Adventitious roots develop where the rhizophores meet the soil. Content Guidelines 2. Each pinna has free to partially anastomosing veins. Plants distinctly delicate and small with two rows of leaves, densely packed in overlapping manner on rhizomatous stem. TOS4. 2. 1901 Oxford University Press This item is part of a JSTOR Collection. Pteridophytes: Features, Classification, Reproduction with Examples - Toppr Leaves pinnate, entire, glabrous, sori elongate to long, sori borne on veins and indusiate; sori lie at wide angle or parallel to the veins; sporangia stalked, spores spheroidal and monolete. Leaves are restricted to the upper side of the rhizome in a single row with adventitious roots on the underside of the rhizome. 2. 3. Sporangia are grouped inter sori, sori more or less elongate. In Lycopodium clavatum stele is plectostelic, i.e. 237,238): 1. Leaves (fronds) are monomorphic and borne in a cluster. Leaves are microphyllous, lanceolate, with distinctly serrate margin. Each leaf has a single vein. So, it is homosporous. There exist variations in the habit of Selaginella. The reproductive structure is a compact one is Selaginella and develops at the terminal portions of branches. The outer cortex shows a ring of large air spaces interspersed with only single rows of cells. Plants homosporous, leaf, 1-2 pinnate, sporangia in sori on the ventral side of the leaf, sporangium with or without indusium. Leaves are monomorphic; lamina is 2 pinnate to 4 pinnate. Plant homosporous, leaf 1-2 pinnate, sporangia in sori on the ventral side of the pinnae, sporangium with indusium. This website uses cookies to improve your experience while you navigate through the website. Sori are long and lie parallel to midrib in a single line. By clicking Accept, you consent to the use of ALL the cookies. Asplenium 13. Other uncategorized cookies are those that are being analyzed and have not been classified into a category as yet. 7. Spores are ellipsoidal, monolete with prominent wing-like folds on surface (Fig. 6. Sori are gradade, cup shaped indusium is present. 11. Anatomy of Lycopodium (With Diagram) | Pteridophyta - Biology Discussion Veins anastomosing, sori sunken and very long near each margin, paraphyses with an enlarged apex. Outermost layer is the epidermis, cells of which have a deposit of silica in their outer and lateral walls. 1. Strobilopterus was a large strobilopterid eurypterid, with adults of the species S. proteus measuring approximately 15 to 20 centimetres in length. Spores are globose to tetrahedral-globose and surface reticulate, cristate or verrucose type. 227) consists of a superficial epidermis, a broad cortex and a central stele or vascular cylinder. In the centre is present a large metaxylem tracheid having many protoxylem groups towards the periphery? Leaves are dimorphic. . In some rare cases branched fertile axis is also present (Fig. Lycophytes are widely . Each mature sporangium is 3-lobed, 2 to 3 mm wide and closely clasped with stem axis by a minute forked foliar appendage. Sori are non paraphysate, but indusiate. Annulus is obliquely placed. (iv) This division contains subdivisions Angiosperms & Gymnosperms. A sporophyll is a leaf that bears sporangia. Sori lie usually parallel or at wide angle to the costa. Mature and young sporangia are mixed together. The cookie is used to store the user consent for the cookies in the category "Other. 238). A. T.S. Leaves are monomorphic with the apical fertile portion somewhat contracted. Each cone or strobilus has a thick central axix known as strobilus axis or cone axis (Figs. Median leaves are serrulate, axillary leaves denticulate. What is a trophic hormone? In T.S. Abaxial surface of Cycas revoluta microsporophyll, showing microsporangia. Spores are spheroidal, monolete with prominent wing-like fold on surface (Fig 6.27). The cookie is set by GDPR cookie consent to record the user consent for the cookies in the category "Functional". Oleandra 20. Each sporophyll bears a sporangium on its adaxial surface. Plant body is sporophytic and the sporophyte is evergreen and perennial. The frond is fleshy and consists of two parts: the vegetative lamina (blade), which is pinnately branched and a fertile spike, which is also similarly branched, bearing sporangia in two rows on ultimate branches. Sporophyte differentiated into stem, leaf and root, stem jointed, siphonostelic; xylem exarch or endarch; sporangia borne oti specialised stalk (sporangiophore) which are organised into strobili, homosporus. The leaflet margin is entire, serrate to crenulate. A T.S. Each vascular bundle is conjoint, collateral, closed, and consists of xylem, phloem and some parenchyma. The plants are epiphytic and stem is short, creeping, small, bearing scales and a few spongy roots. (Fig 6.32). Stem mono or polyprotostelic or siphonostelic; sporangia short stalked, single, near the axil of a leaf. You also have the option to opt-out of these cookies. This evolutionary convergence is not unusual, since the form of a strobilus is one of the most compact that can be achieved in arranging lateral organs around a cylindric axis, and the consolidation of reproductive parts in a strobilus may optimize spore dispersal and nutrient partitioning. Stomata are present on both the surfaces of the leaf. Sori are located near the margin of lamina. It is wavy in outline because of the presence of ridges and grooves. The xylem is C- or U-shaped (Fig. Leaves are monomorphic and unipinnate, glabrous and with free veins. Explain with suitable example. The sporangia, instead of being all alike, are of two distinct kinds. 3 Modes of Reproduction found in Rhodophyceae or Red Algae. On the stem leaves are loosely arranged in spiral fashion. Margin of the fertile segment modified as an indusium, sporangia distant on the veins of the unipinnate fertile lamina. Vascular bundles are collateral and endarch. It is photosynthetic in function. 237). 239 E, F). The leaves are borne in acropetal order overlapping one another and taper abruptly from a broad base to an elongated acicular limb. Sporangia are grouped together as sori. Updates? This cookie is set by GDPR Cookie Consent plugin. Except in a few species, sporangia are fully covered by sporophylls. Fronds are 1 veined, broad, lanceolate- oblong, bi-pinnatifid, and leaf segment hairy. We also use third-party cookies that help us analyze and understand how you use this website. A sporophyll bears a single flattened, oval or rounded sporangium between the ligule and the leaf base on the adaxial face. The stele is monarch, diarch or triarch with one, two or three protoxylem groups, 5. Lycophyte sporangia are associated with leaves and often form strobilus which is a condensation of sporangia-bearing leaves ( sporophylls when they are leaf-like or sporangiophores when they are divergent). 4. Each spore is uninucleate and the cytoplasm contains few chloroplasts. Stem ribbed, siphonostelic with endarch xylem, presence of conspicuous protoxylem lacunae (carinal canal), spores with elaters. 246). The plant has a short erect stem with branches without any hairs. Which types of bacteria are used in Bt-cotton? The branching is monopodial. Fertile region is represented by strobili (Fig. Share Your PPT File. Spores are tetrahedral, globose and trilete (Fig 6.19). On the strobilus axis the sporophylls are arranged spirally. preservearticles.com All rights reserved. Leaves are monomorphic, with pinnatifid lamina. Sporangium is stalked and bears vertical to oblique annulus. through rhizomatous stem shows central siphonostelic core with parenchymatous cortex. The stem is closely covered spirally by small, simple (microphyllous), sessile, lanceolate leaves with mildly serrate margins and single median veins. You also have the option to opt-out of these cookies. ex Schrank et Mart. Plants homosporous, leaf 1-2 pinnate, sporangia in sori on the ventral side of the leaf, sporangia with indusium, sporangial development gradate or mixed. 2. 6.2: Pteridophyta - the Ferns - Biology LibreTexts Sporocarps are dimorphic, sporangia are borne in short stalked sori on the lower lobe and are enclosed by an indusium and so forming a sporocarp. A T.S. In 5. kraussiana stele is distelic. Each bundle is covered by endodermis, or both endodermis and pericycle are continuous. Oleandra 20. In this article we will discuss about the anatomy of equisetum. Receptacle is incited within indusium and not paraphysate. Margin of the fertile leaf segment is modified as an indusium. There are many, persistent, filamentous, branched paraphyses in the sorus. Sporangium is stalked and annulus is vertical in position.
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