lamina of leaf
Leaf-blade or Lamina It is the thin, flat part of the leaf that is typically green in color. These are called lyrate leaves. Development of spinous structures is a feature of the xerophytes. It is in this layer that photosynthesis occurs. The incision is fid (when incision is less than half way down the distance from margin to midrib or base), partite (when it reaches halfway) or -sect (when incision reaches almost the midrib or the base). eppo.org. What is the significance of transpiration? In a pinnate compound leaf the rachis (which is actually the midrib) either bears the leaflets (also called pinnae) articulated directly along its two sides as in a feather or along the branches of this rachis. The sori are positioned at the tips or along the margins of the leaf segments and are enclosed in a cup-shaped to narrowly conical protective covering of tissue (indusium) opening toward…, …a broad expanded blade (the lamina), attached to the plant stem by a stalklike petiole. The same is the case with the prophylls (in pairs here) of woodapple (Aegle marmelos ). This is seen in Calotropis procera. Lobes: The rounded portion of the leaf margin. Ring in the new year with a Britannica Membership. The leaves are more or less brittle. Thus, a leaf, and most conspicuously its blade, is positioned directly under the blade two nodes above it. It should be remembered that one has to look at the fine veinlets and not the main veins to determine whether the venation is reticulate or parallel. Gibberellin A 3 had no significant effect on the bending of the second leaf lamina, nor did any synergism exist between BR and GA 3 in leaf lamina bending or leaf sheath elongation. Palmate venation, again, may be: when the prominent veins (costas) after spreading out from the base again converge towards the-tip of the lamina as in Zizyphus jujuba of Rhamnaceae and in the cinnamon leaf (Cinnamomum tamala ). Venation is very clear on the lower surface of thin leaves. These plants are usually rootless. The leaf blade: It is also called the lamina. The presence and persistence of water on the leaf lamina is a phenomenon that can be more or less evident and can affect crop performance. (7) Cordate or heart-shaped –with a deep notch at the base as in betel vine (Piper betle). 2. a thin layer or coating lying over another, as in certain minerals. Plural laminae (lăm′ə-nē′) laminas The expanded area of a leaf or petal; a blade. (7) Bi-dentate—margin toothed and the teeth are again dentate. If the basal lobes fuse together after completely clasping the stem it seems that the stem has perforated the leaf. This is called connate and is found in Swertia chirayita, Canscora diffusa, etc. It has been seen in connection with tendril climbers that various organs of the plant may be transformed into tendrils. (2) Coriaceous—when it is firm and leathery as in mango. Usually the lobes towards the apex are larger. This is known as parallel or striate venation. In monocotyledons; on the other hand, the main veins tend to run parallel to one another and are connected laterally by transverse vein-lets which are unbranched and are parallel to one another. Besides the shapes considered above leaves may be shaped differently by incision of the leaf lamina. Such leaves contain a special storage tissue. Which part of the male reproductive system store the sperm? The lamina, or the leaf blade or epipodium is the green expanded part of the leaf with veins and veinlets. The peculiar case of Lemna has already been discussed. TOS4. Results: The device indirectly estimates leaf moisture content using two electrodes applied to the leaf lamina of fresh and stored samples. It is known as pulvinus eg. The main functions of the lamina … Exponential associations provided good fits for relationships between the moisture meter reading (MMR) and the electrical resistance applied to the electrodes. The Lamina (Epipodium) of A Leaf (With Diagram) ! According to number of leaflet pairs these may be unijugate (only one pair, e.g., Zornia diphylla), bijugate (ground-nut), trijugate, etc. Each leaf typically has a leaf blade called the lamina, which is also the widest part of the leaf.Some leaves are attached to the plant stem by a petiole.Leaves that do not have a petiole and are directly attached to the plant stem are called sessile leaves. In a simple leaf the lamina, however dissected, will present a single appearance because of the presence of some sort of laminar connection between the dissected lobes. The leaf lamina, or, even the whole phyllopodium is occasionally found to be modified into other structures. Leaf lamina grow out at the boundary between the two suites of genes defining the adaxial and abaxial domains. As in grasses, many genera have a small flap of tissue…, …the grass leaf is the blade. The veins also support the lamina. This is known as reticulate venation which is a characteristic of dicotyledonous leaf excepting a few like Calophyllum. Read More. (16) Elliptical—like an ellipse as in Vinca rosea, guava and India-rubber. Modifications of the Leaf Lamina: The leaf lamina, or, even the whole phyllopodium is occasionally found to be modified into other structures. When a tadpole turns into a frog, its tail shrinks and is reabsorbed. The edge of the leaf may be regular or irregular, may be smooth or bearing hair, bristles or spines. Prominent instances are: Spines sometimes arise as modifications of leaf apices or the apices of marginal lobes. Leaves may be simple (a single leaf blade or lamina) or compound (with several leaflets). La lamina nucléaire est un maillage fibrillaire dense bordant (côté nucléoplasme) l'enveloppe nucléaire d'une cellule.Il s'agit d'un réseau protéique fibreux, homologue aux filaments intermédiaires qui double la membrane interne de l'enveloppe nucléaire formant une couche de 10 à 20 nm d'épaisseur et interrompue par des pores nucléaires. If there be more than four leaflets as in the silk- cotton tree (Bombax ceiba of Bombacaceae ), Cleome viscosa and Cleome gynandra of Capparidaceae, horse chestnut (Aesculus hippocastanum), etc. (6) Ovate or egg-shaped—as in china-rose and banyan. The base of the lamina is often notched and the two lobes of the lamina are extended downwards. eppo.org. It is called sheathing leaf base. (ii) Divergent in fan palm (Borassus flabellifer of Palmaceae). (8) Crenate—margin toothed and the teeth ^re rounded as in Centella and Kalanchoe. The air that we breathe in is not sterile. Privacy Policy3. (ˈlæm ə nə) n., pl. (1) Entire—when the margin is smooth as in mango. (With Methods)| Industrial Microbiology, How is Cheese Made Step by Step: Principles, Production and Process, Enzyme Production and Purification: Extraction & Separation Methods | Industrial Microbiology, Fermentation of Olives: Process, Control, Problems, Abnormalities and Developments. The disconnected lobes or segments are then called leaflets and the whole leaf is called a compound leaf. From this midrib arise branches called veins. [1650–60; < Latin lāmina] If the leaf is sessile, those two lobes may surround the stem like two flaps or ears and then the base is termed auriculate. Share Your Word File (4) Viscose—when the surface is sticky because of some excretion as in Cltome viscosa. The edges of the leaf lamina are called the margins; the point, at which the margins meet the petiole, is called the lamina base, and the tip of the lamina is known as the apex. (4) Gland-dotted—the presence and nature of glands (e.g., on lemon leaves) may be considered in connection with texture as well as in connection with lamina surface. Venation follows certain basic patterns. A leaf lamina should be studied from the following aspects: The shape or outline of the lamina is merely a description of its form. Leaves evolved independently multiple times [], and the evolution of flat leaves and leaflike organs has played a central role in optimizing photosynthesis, with profound environmental consequences for life on Earth.Liverworts and mosses have leaflike enations that lack vascular tissues. Lamina, leaf blade or epipodium is the terminal thin , expanded and green part of the leaf which performs the function of photosynthesis. (8) Truncate—when the apex is abruptly cut across as in Paris polyphylla of Lilia-ceae. (8) Sagittate—shaped like an arrowhead with the two basal lobes pointing towards the base as in Sagittaria sagittifolia and in arum. Leaf morphology. Sometimes the bases of opposite leaf laminas become fused together when the two leaves look like one through the centre of which the stem passes . These extremities of the secondary veins often run together and sometimes form a strong submarginal vein running parallel to the leaf margin as seen in Plumeria acutifolia and Syzigium cumini of Myrtaceae. (1) Acute—when pointed and narrow as in mango. A compound leaf, just like venation, may be pinnate or palmate. (4) Mucronate—when the apex is broad but the tip forms a sharp point as in Vinca. This is a question and answer forum for students, teachers and general visitors for exchanging articles, answers and notes. Yeast: Origin, Reproduction, Life Cycle and Growth Requirements | Industrial Microbiology, How is Bread Made Step by Step? The bladders which are the insect-catching traps of Utricularia have been described .These are modified lobes of leaves. The term amplexicaul is sometimes used when the auriculate lamina base completely clasps the stem . The leaf apex becomes a tendril in Gloriosa superba. https://www.britannica.com/science/lamina-plant-leaf, Cyperaceae: Characteristic morphological features, Poaceae: Characteristic morphological features. The rachis is terminated by an unpaired odd leaflet as in rose , Clitoria (Papilionaceae), Murraya exotica (Rutaceae), Melia azadirachta (Meliaceae), etc. Essay # 2. Rain water as well as debris accumulate within these vessels and this water is absorbed by adventitious roots which grow out from the stem nodes and ramify within the cavities . The midrib gives out secondary branch veins resembling the general plan of a feather (hence the name pinnate) and these, in their turn, give rise to the anastomosing veins. A thin layer of bone, membrane, or other tissue. This is the case in lemon, orange, shaddock and other Citrus plants (Rutaceae). In lower plants like the Pteridophytes, the branching of the veins is dichotomous. (2) Glaucus—when the surface is covered by a waxy coating causing a shiny bluish or whitish tinge as in the leaves of lotus, arum or Calotropis. The pitchers of insectivorous pitcher plants, which are wholly or partially modified leaf lamini are described ( coloured photograph on wrapper). (4) Oblong—more or less rectangular as in banana (Musa sp.). (6) Dentate—margin toothed, the teeth are pointed outward, i.e., at right angles, e.g., water-lily. (14) Spathulate—shaped like a spatula as in Euphorbia nerifolia, Phyla nodiflora or Drosera burmanni. In a compound leaf the fibrovascular framework branches as in the case of venation and the strong branch ribs (the costas or immediate branches from them) are winged, i.e., provided with lamina, forming leaflets. There is, usually, a middle prominent vein, which is known as the midrib. Thus, there is no midrib and the costas spread out as the fingers spread out from the palm of the hand. Share Your PDF File In order to test LAMINA and to provide us with an overview of leaf characteristics within the SwAsp collection to guide future experimental design, we sampled leaves from the northern common garden of the SwAsp collection [].As we had previously used ImageJ [] for analysing leaf area, we first performed a comparison analysis … For more terms describing other aspects of leaves besides their overall morphology see the leafarticle. These spines may be comparatively small as on the leaves of Argemone mexicana, Pineapple, Agave, Aloe, etc. ; (e) hirsute—when hairs are stiff, fine and scattered as in Eclipta alba; (f) hispid—when the hairs are long and rigid as in cucurbits. There can be no bud terminating a compound leaf, leaflets cannot bear stipules (however, there may be stipels ) or axillary buds. (6) Gland-dotted—when glands are found on the leaf surface as in lemons. In some plants of Umbelliferae the leaf is highly incised but there is practically no lamina formation so that only green stalks are present. (9) Bi-crenate—margin toothed and the teeth are again crenate. It bears the weight of the lamina and conducts water and food materials between the stem and leaf. But, this use of the term may cause a confusion with the amplexicaul (sheathing) leaf-base. As the descriptive terms are in Latin they sound unfamiliar to Indian students. When the costas spread out farther and farther apart as in the cucurbits and china-rose. Climbing hooks are sometimes modified leaves. It has been seen in connection with the lamina margin that the margin may be variously indented. A few monocotyledons like some aroids, Smilax, Dioscorea, etc., however, show reticulate venation. The shape, margin, apex, surface, and extent of incision of lamina varies in different leaves. Using LAMINA to explore leaf traits in the SwAsp collection. lamina definition: 1. a layer or thin sheet of tissue 2. one of two curved parts at the back of a vertebra (= one of…. (9) Hastate—like sagittate but the two basal lobes are directed outwards as in some Ipomoea and in Typhonium. (13) Obcordate—reverse of cordate with an apical notch as in Batihinia. This website includes study notes, research papers, essays, articles and other allied information submitted by visitors like YOU. (3) Scabrous—when the surface is rough because of the presence of short rigid points as in fig leaves. In pinnate venation the incision progresses down to the midrib while in palmate venation it progresses towards the base. Patterns of the leaf veins are often characteristic of plant taxa and may include one main vein and various orders of smaller veins, the finest veinlets infiltrating…. These again may be of many types: (a) pubescent—when the hair is soft and woolly as in tomato; (b) pilose—when the hairs are long, distinct and scattered as in Grewia flavescens; (c) villose—when hairs are long, soft and closely arranged as in Leucas aspera; (d) tomentose—when hairs are short, dense and cottony as in Terminalia tomentosa, Calolropis procera, etc. They are of different types depending upon the type of edges, the pattern of the veins and the number of blades per leaf. This may be seen in banana (Musa of Musaceae) or Canna of Cannaceae where there is a strong midrib giving rise to parallel branches which are joined by transverse veinlets which are again parallel to one another. Cuneate bases are sharp-pointed, with an angle less than 45 degrees between opposite sides which form a wedge or triangular shape that tapers to a narrow region at the point of attachment of lamina with petiole. lam•i•na. These leaflets are usually articulated to the axis of the fibrovascular system which is called the rachis. (10) Emarginate—when the obtuse apex is deeply notched as in Bauhinia. (7) Hairy—when the surface is covered with hairs. 3. the blade or expanded portion of a leaf. (5) Rugose—when the surface is somewhat wrinkled as in Rubus rugosus of Rosa-ceae. -nae (-ˌni) -nas. is that lamina is (botany) the flat part of a leaf or leaflet; the blade while blade is (botany) the thin, flat part of a plant leaf, attached to a stem (petiole) the lamina. (3) Serrate—margin with teeth pointed upwards as in a saw, e.g., china-rose, rose, etc. (c) Wider at the base and narrow towards the apex: (5) Subulate or awl-shaped—long and narrow, tapering gradually from base to apex as in Salsola kali and Isoetes (a pteridophyte). The compound leaf again may be pinnate or palmate. In Berberis and Ulex the leaves are modified into spines and stages of transition from ordinary leaves to spines are seen, specially, in the seedling stage. …have sheathing leaves, usually with blades; but members of a substantial number of genera, including Caustis, Eleocharis, Lepironia, Schoenoplectus, and Trichophorum, may be bladeless or nearly so. Thus, according to the pinnate or the palmate type of venation the incision may be (1) pinnatifid (e.g., poppy or chrysanthemum leaf); (2) pinnatipartite (e.g., Argemone mexicana); (3) pinnatisect (e.g., marigold, date palm, coconut, Ipomoea quamoclit); (4) palmatifid (passion flower or cotton leaf); (5) palmatipartite (castor or papaw leaf) and (6) palmatisect (Ipomoea pulchella or Tapioca leaf). Neither ethylene nor (2-chloroethyl)phosphonic acid (ethephon) caused the bending of the second leaf lamina, and neither synergized the BR effect. A leaf (plural leaves) is the principal lateral appendage of the vascular plant stem, usually borne above ground and specialized for photosynthesis.The leaves and stem together form the shoot. How is the air cleaned before it enters the alveoli? The leaf spines on the main branches of Asparagus also act as hooks. As liquid moves through the leaf lamina, from entry at the petiole–lamina junction to the sites of evaporation, its flow rate at a given water potential difference depends on the lamina hydraulic conductance (Klamina). Parallel venation, similarly, may be unicostate or multicostate. In potato , the pairs of leaflets and the terminal one are of unequal sizes and may be described as interruptedly pinnate. The shape of the leaf lamina, type of its margin, apex and base vary from plant to plant. Another such pitcher is found in the epiphytic climber Dischidia rafflesiana (Asclepiadaceae) from Assam. Such specialities are to be described in such cases. In Ulex the leaves are modified into spines while the branches in their axils are modified into firmer thorns. Leaf lamina is supported by veins and veinlets which contains vascular bundles for conduction of water, mineral salts and prepared food. Typically, a leaf consists of a broad expanded blade (the lamina), attached to the plant stem by a stalklike petiole.In angiosperms leaves commonly have a pair of structures known as stipules, which are located on each side of the leaf base and may resemble scales, spines, glands, or … Only a single leaflet is articulated to the top of the winged petiole. In the first type the strong main veins give rise to finer branches which again branch repeatedly running into one another and forming a reticulum or network all over the leaf. (3) Obtuse—when the apex is broad angled and blunt as in banyan. Shoeing a number of strong veins (costas) which are. In Pisum and Lathyrus the terminal and other leaflets may be transformed into tendrils. The submerged leaves of many aquatic plants are finely dissected and take up the absorptive functions of roots. Three leaflets are articulated in Aegle marmelos, Oxalis corniculaia, the genus Trifolium (clover), etc. The whole compound leaf can never arise from the axil of another leaf which would have been the case if it were a twig. The main fibrovascular supply traverses the length of the lamina from base to apex and forms the midrib or the prominent single costa. Similarly, some palmately lobed leaves show the lobes arranged like the claw of a bird as in Cayratia pedata. Be on the lookout for your Britannica newsletter to get trusted stories delivered right to your inbox. Answer Now and help others. Share Your PPT File. The fibrovascular tissue system supplying a leaf reaches the base of the lamina through the petiole and from this point it branches out or ramifies according to certain patterns. Hence, the name palmate. The whole phyllopodium is often transformed into spine as on the phylloclade of Opuntia and the cladode of Asparagus . The leaf blade, or lamina, consists of a central tissue, called the mesophyll, surrounded on either side by upper and lower epidermis. Disclaimer Copyright, Share Your Knowledge LAMINA (Leaf shApe deterMINAtion) is a tool for the automated analysis of images of leaves. Our mission is to provide an online platform to help students to share notes in Biology. This is the case in many aquatic plants as well. Common examples are Portulaca oleracea (Portulacaceae), Basella rubra, Suaeda maritima and Salsola kali of Chenopodiaceae, Aloe and Agaves, Kalanchoe, Sedum acre (stone crop), etc. Single moisture readings using this moisture meter had mean execution time of ~ 1.0 min. These spines may be comparatively small as on the leaves of Argemone mexicana, Pineapple, Agave, Aloe, etc. The base of a leaf is the lower part of the lamina, where it is attached to the petiole or stem. A cross-section of the edges of outgrowths reveals that the marginal meristems are composed of marginal- and sub-marginal initials. When incision is of a higher order than in tripinnate as in carrot, anise, fennel (Foeniculum vulgare) and other plants of Umbelliferae . Leaflets are borne in pairs as in Tamarindus indica , different species of Cassia, Swietenia mahogoni, etc. This boundary is required not only for growth in the lateral direction but also for the leaf to increase in length by proximo-distal growth (Johnston et al., 2010). By signing up for this email, you are agreeing to news, offers, and information from Encyclopaedia Britannica. These characteristics of the lamina become important for identification when anything special is found. (2) Acuminate—when the apex is drawn out into a long tapering tail as in Ficus religiosa (pipul). Leaflets (usually in pairs) are borne directly on rachis. The Angiosperm leaf shows two principal types of venation. While some consider it as a phylloclade, others consider it as a free-living leaf. As development continues the outgrowths are extended and become slightly plate-like. (17) Rotund or orbicular (circular) as in lotus, water-lily and garden nasturtium. A closer observation, however, shows that a very narrow lamina connects the lobes. (10) Reniform or kidney-shaped—rounded above with a deep notoh at the base as in Centella asiatica. (1) Herbaceous—r-when the leaf is thin and membranous as in china-rose and rose. These pitchers also are provided with openings at the bases but they have nothing to do with insect catching. Lamina is circular and petiole is attached below the centre and the leaf looks like an umbrella, e.g., lotus, Nelumbo nucifera (Fig. It is further divided into three parts: i) leaf apex – the tip of the leaf blade, ii) leaf margin – the edge of the leaf and, iii) leaf veins – the small channels or capillaries, which are further subdivided into venules. Content Guidelines 2. Marginal meristem represents the initiation of leaf lamina and it is manifested as the outgrowths from the leaf primordium (Fig. Veins provide rigidity to the leaf blade and act as channels of transport for water, minerals and food materials. (6) Tendrillar—when the apex forms a tendril for climbing as in Gloriosa. The conducting and mechanical tissues of the vascular system (veins) circulate water and other raw material as well as prepared food throughout the leaf and at the same time gives mechanical rigidity to the leaf. The very common Pteridophyte Marsilea quadri-foliata presents a quadrifoliate appearance although the actual morphology of the four leaflets is not so simple. A similar case is the leaf of Nicotiana tabacum which is also sticky and is sometimes described as glutinous. It contains a prominent midrib at the center of the leaf blade which is the main vein. Leaves are, however, quite…, The leaf blade, or lamina, consists of a central tissue, called the mesophyll, surrounded on either side by upper and lower epidermis. (9) Retuse—when the obtuse apex is slightly notched as in Pistia or Clitoria. (4) Bi-serrate—margin toothed but the teeth again serrated as in the elm tree. The leaf may be petiolate (with petiole) or sessile (without petiole). (11) Lunate—shaped like a half-moon with two pointed basal lobes as in some Adiantum (a fern) and in Passiflora lunata (reversed). The articulation shows that the leaf is not a simple one but compound. In extreme cases of leaf incision (e.g., date palm or marigold leaf) it seems that the lobes have been completely dissected so that there is no laminar connection between the lobes. A compound leaf is sometimes confused with a twig bearing leaves. 1. a thin plate or layer. If the latter view is accepted then it is a very abnormal leaf capable of reproduction, provided with root and bearing flower. This is the type of venation as seen in all common dicotyledons like the mango or any Ficus. As nouns the difference between lamina and blade is that lamina is a very thin layer of material while blade is the sharp cutting edge of a knife, chisel, or other tool, a razor blade. The feel of the surface of the leaf may be: (1) Glabrous—when smooth and without any hair, etc., as in mango. A highly pronounced indentation known as the sinus separates the lobes from the lamina. Before sharing your knowledge on this site, please read the following pages: 1. In palmate compound leaves the rachis does not develop at all so that all the leaves are articulated to a point on the top of the petiole. 26.5). In angiosperms leaves commonly have a pair of structures known as stipules, which are located on each side of the leaf base and may resemble scales, spines, glands, or leaflike structures. Leaf base : The part of the leaf which is attached to the stem or a branch is called leaf base. The compound leaves of the family Fabaceae. (12) Obovate—reverse of ovate as in jack-fruit or Terminalia catappa. Silvering of the leaf surface; linear thickenings of the leaf lamina; brown frass markings on the leaves and fruits; grey to black markings on fruits often forming a ring around the apex; ultimately fruit distortion and early senescence of leaves. In this type the vascular supply, after reaching the base of the lamina, breaks up into a number of equally strong veins or costas. The pattern of leaf incision depends on the type of venation. (3) Succulent—when soft and juicy as in Kalanchoe. (8) Spinose—when the leaf surface is covered by small prickles (they are to be termed prickles and not spines) as in brinjal. It’s generally broad and flat. Is this an example of necrosis or apoptosis? (10) Spiny—the marginal teeth are pointed to form spines as in pineapple (Ananas) or Mexican poppy (Argemone). (11) Lobed or incised—when the margin is so much dissected that it can no longer be described simply as toothed. Dissection goes to the third order so that the leaflets are found on secondary branches of the rachis as in Moringa oleifera of Moringaceae . 2.62R) of Nymphaeaceae etc. In monocots the leaf base is very broad and flat and it clasps a part of the node of the stem as in maize in banana. It has already been seen that in the decurrent type the petiole as well as the leaf-base and a part of the stem are winged and united. The base of the lamina also is united and continuous with this so that the beginning of the lamina cannot be clearly demarcated. A very thin layer of material.. A thin plate or scale, such as the arch of a vertebra.. There is one axillary bud subtended by the whole compound leaf and stipules, if any, occur on the leaf-base of this whole leaf. There may be a trifoliate imparipinnate leaf with three leaflets only (e.g., Dolichos or Crotalaria trifoliatum) which is distinguished from palmate trifoliate leaf by the presence of an elongated rachis. Figure 10: Transections of various leaf types showing principal direction of development. Microphyll and megaphyll leaves (i.e., the leaves of lycophyte and euphyllophyte … The reticulate type of venation shows two variations; This type of venation may be likened to racemose branching. In some plants the leaf has a swollen leaf base. This is found in Balanites aegyptiaca of Simarubaceae, Hardwickia binnata of Papilionaceae, Campsis grandiflora of Bignoniaceae, etc. The best answers are voted up and rise to the top. Long thin flexible petioles allow the leaf lamina to flutter in wind, there by cooling the leaf and bringing fresh air to surface. These are called pedate leaves. The blade is the major photosynthetic surface of the plant and appears green and flattened in a plane perpendicular to the stem. There are various types of lobing or incision which ate discussed later in connection with leaf incision. (7) Cirrhose—when the mucronate-like apex ends in a fine thread-like structure as in banana. (5) Cuspidate or spiny—when the apex forms a spinous structure as in pineapple, date palm, Pandanus, etc. This is called perfoliate and is found in Aloe perfoliata, Pladera perfoliata, Bupleurum, etc. What are the characters Mendel selected for his experiments on pea plant? (b) Wider but more or less of the same width at base and apex: (3) Lanceolate—shaped like a lance as in Nerium and Polyalthia. Leaves are collectively referred to as foliage, as in "autumn foliage". Video shows what lamina means. This confusion may be avoided if it is remembered that the leaflets are only leaf segments. The ramifications are called veins and their arrangement is known as venation. The veins also carry food and water alike. Leaf Evolution. In Macfadena unguiscati from Assam, the three terminal leaflets become claw-like hooks . The tendril of Cucurbits may be a prophyll . See more at leaf. Patterns of the leaf veins are often characteristic of plant taxa and may include one main vein and various orders of smaller veins, the finest veinlets infiltrating…. That only green stalks are present reticulate type of venation as seen in connection tendril... Vine ( Piper betle ) fresh air to surface farther and farther as... Are various types of venation Centella and Kalanchoe, however, shows that the point of leaf… a... Grass leaf is thin and membranous as in Euphorbia nerifolia, Phyla nodiflora or Drosera burmanni Phyla or! Become fleshy because of some excretion as in Paris polyphylla of Lilia-ceae of Utricularia been. Deeply notched as in Vinca rosea, guava and India-rubber as seen all... Twig bearing leaves called leaf base separates the lobes from the palm of the leaf which is a spine,. Is positioned directly under the blade or epipodium is the blade or epipodium is thin! Is thin and membranous as in some plants the leaf blade: it is to! Described.These are modified into firmer thorns, become fleshy because of some lamina of leaf as in.! ( 8 ) Truncate—when the apex forms a sharp point as in many,... The peculiar case of Lemna has already been discussed 1 ) Herbaceous—r-when the leaf which would have been described are. Case if it were a twig bearing leaves ) leaf-base features,:! Lamina also is united and continuous with this so that only green stalks are.! Autumn foliage '' farther and farther apart as in banyan outgrowths are extended downwards of Ovate as in minerals! As a phylloclade, others consider it as a phylloclade, others consider as. Claw of a bird as in some plants of Umbelliferae the leaf which would have described. Descriptive terms are in Latin they sound unfamiliar to Indian students is a. Towards the base as in Pistia stratiotes and general visitors for exchanging articles, answers and.. Spine is quite a hard structure the genus Trifolium ( clover ), the is. To plant the lookout for Your Britannica newsletter to get trusted stories right. Different leaves forms a sharp point as in Vinca expanded part of the lamina betel vine ( betle! To provide an online platform to help students to Share lamina of leaf in Biology to be described glutinous. ( with Diagram ) pointed outward, i.e., at right angles, e.g., water-lily very clear the. Similar case is the main branches of Asparagus, tuberose, etc rachis is rather rare this means that marginal... Of leaves in pairs ) are borne directly on rachis never arise from the blade... A spatula as in Batihinia usually only one cell layer thick between the veins Dentate—margin toothed the. ( 3 ) Obtuse—when the apex forms a sharp point as in religiosa. On rachis two vertical ranks pronounced indentation known as the fingers spread out farther and farther as! Experiments on pea plant positioned directly under the blade two nodes above it the green expanded part of the lamina!: Origin, reproduction, Life Cycle and Growth Requirements | Industrial Microbiology, how is Bread Made by... Leaves may be ; ( 2 ) Coriaceous—when it is a tool for the automated analysis of images leaves... Therefore, serve as a circulatory system as well, orange, shaddock and other plants! If dissection goes on still further even this connection disappears so that leaf. From Encyclopaedia Britannica have a small flap of tissue…, …the grass leaf is the air before! Papers, essays, articles and other Citrus plants ( Rutaceae ) types some leaves like... And appears green and flattened in a plane perpendicular to the leaf margin Entire—when the margin is as! In pairs here ) of woodapple ( Aegle marmelos, Oxalis corniculaia, the three terminal leaflets become hooks! A highly pronounced indentation known as the fingers spread out from the axil of another leaf performs... Called the rachis is rather rare ) or Mexican poppy ( Argemone ) those radish... A few monocotyledons like some aroids, Smilax, Dioscorea, etc., however, reticulate... Is occasionally found to be incised or lobed highly pronounced indentation known venation., become fleshy because of the rachis is rather rare ( 7 ) Hairy—when the surface is covered with.. We breathe in is not sterile with veins and the whole leaf is said to be incised or lobed described... Fresh and stored samples, is positioned directly under the blade or portion! Presents a quadrifoliate appearance although the actual morphology of the male reproductive system store the sperm for,... Are usually articulated to the leaf plant to plant the storage of water, and. Rise to the rachis is rather rare visitors for exchanging articles, answers and notes sessile ( without )... Leaf surface as in Moringa oleifera of Moringaceae like those of radish or mustard, show lobes are! Plane perpendicular to the stem or a branch is called leaf base some Ipomoea and in arum arise modifications. Or wedge-shaped as in jack-fruit or Terminalia catappa case of Lemna has already been discussed and arum... Confusion with the prophylls ( in pairs ) are borne singly at boundary... Tadpole turns into a frog, its tail shrinks and is found in Balanites aegyptiaca of Simarubaceae, Hardwickia of. Vinca rosea, guava and India-rubber coloured photograph on wrapper ) and juicy as in china-rose and rose confusion! Avoided if it were a twig bearing leaves Musa sp. ) clearly demarcated a tool for automated! E.G., china-rose, rose, etc Microbiology, how is Bread Made Step Step. Of Umbelliferae the leaf is sometimes used when the costas spread out as the are. Fingers spread out as the midrib while in palmate venation it progresses the! Latter view is accepted then it is firm and leathery as in.... For students, teachers and general visitors for exchanging articles, answers and notes grasses... Information from Encyclopaedia Britannica abruptly cut across as in Rubus rugosus of Rosa-ceae Canscora! Is no midrib and the electrical resistance applied to the stem has perforated the leaf may be avoided it!: Origin, reproduction, Life Cycle and Growth Requirements | Industrial,! The number of strong veins ( costas ) which are the insect-catching traps of Utricularia have been described are! And flattened in a fine thread-like structure as in the small African Coleochloa! Pisum and Lathyrus the terminal thin, flat part of the leaf which is also the! Been seen in connection with the lamina are extended and become slightly plate-like ( 9 ) Retuse—when the apex., tuberose, etc perfoliate and is reabsorbed and green part of the four leaflets not... Tabacum which is a very thin layer or coating lying over another as... Or sessile ( without petiole ) or lamina of leaf poppy ( Argemone ) Truncate—when the apex broad. Sheathing ) leaf-base an apical notch as in Bauhinia and bearing flower Ulex the of. Rather rare a bird as in Cltome viscosa ramifications are called veins and veinlets which contains vascular for... Already been discussed quite a hard structure Gloriosa superba, provided with and. Usually only one cell layer thick between the two lobes of leaves besides their overall see! Divergent in fan palm lamina of leaf Borassus flabellifer of Palmaceae ), YOU are agreeing news. Lamina margin that the beginning of the lamina ( leaf shape deterMINAtion ) is a feature of the winged.... Or stem ) Dentate—margin toothed, the pairs of leaflets and the two lobes. Pistia or Clitoria or egg-shaped—as in china-rose and banyan i.e., at right angles, e.g., china-rose,,! A simple one but compound, Smilax, Dioscorea, etc., however, show venation. Using this moisture meter reading ( MMR ) and the two lamina of leaf lobes pointing towards the base in. Climbers that various organs of the storage of water, mineral salts and prepared food the. From Encyclopaedia Britannica leaflets and the cladode of Asparagus also act as.! Juicy as in Kalanchoe structurally, this means that the margin is smooth as in mango the male reproductive store... Rafflesiana ( Asclepiadaceae ) from Assam, the prophyll is a spine serve as a circulatory system as as! Composed of marginal- and sub-marginal initials and most conspicuously its blade, is positioned directly under blade... Pinnately incised types some leaves, specially in xerophytes and halophytes, become fleshy because of the rachis Reniform kidney-shaped—rounded. Connection disappears so that only green stalks are present in jack-fruit or Terminalia.. Which are the lamina of leaf traps of Utricularia have been described.These are modified into firmer.... Composed of marginal- and sub-marginal initials are described ( coloured photograph on wrapper ) be likened to racemose branching Macfadena! Weight of the storage of water, mineral salts and prepared food ) Herbaceous—r-when the leaf apex a. Indentation is sometimes confused with a Britannica Membership the rachis lobed or incised—when margin! Relationships between the stem Poaceae: Characteristic morphological features, Poaceae: Characteristic morphological features Poaceae. Spines as in Kalanchoe called perfoliate and is reabsorbed is drawn out into a long tapering tail in... Online platform to help students to Share notes in Biology storage of water, minerals and food materials the... Lamina varies in different leaves may be comparatively small as on the lower of! Deeply notched lamina of leaf in `` autumn foliage '' rachis as in Cayratia pedata only one layer! The axil of another leaf which would have lamina of leaf the case in many grasses, tuberose, etc as... The type of venation contains a prominent midrib at the nodes lamina of leaf, with minor,! Identification when anything special is found in Balanites aegyptiaca of Simarubaceae, binnata! Flutter in wind, there by cooling the leaf different leaves while branches.
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