The petiole LEAF STRUCTURE & FUNCTION 2. Tip/Leaf Apex: This is the tip of the leaf . Which of the following is true of a petiole? Example: Moringa oleifera (drumstick), In this type, the rachis gets branched thrice or more than thrice and the leaflets arise on the ultimate branches. A key innovation in leaf evolution is the acquisition of a flat lamina with adaxial-abaxial polarity, which optimizes the primary function of photosynthesis. onion, garlic, etc. It protects the young axillary bud. plants the shape and form of leaves are such that it is difficult to What is the WPS button on a wireless router? Leaves do not shade each other To trap as much light as possible 4. Many people often call it a stem, which is incorrect. The lamina, or the leaf blade or epipodium is the green expanded part of the leaf with veins and veinlets. Multiicostate convergent parallel Venation, Multiicostate Divergent parallel Venation. and thin, to expose the chloroplast containing cells (chlorenchyma) The main functions of the lamina are photosynthesis and transpiration. Leaf margins of simple leaves may be lobed in one of two patterns, pinnate or palmate. asked May 12, 2018 in Class XI Biology by aditya23 (-2,145 points) morphology. There is, usually, a middle prominent vein, which is known as the midrib. e.g. an above-ground organ specialized for photosynthesis. The leaves with stipules are called stipulate leaves and the leaves without stipules are called ex-stipulate leaves. In some leguminous plants, the leaf base may become swollen, which is called the pulvinus. The arrangement of veins and the veinlets in the lamina of the leaf is termed as venation. If the number of leaflets is odd it is known as imparipinnate compound leaf and if it is an even then it is known as a paripinnate compound leaf. Who is the longest reigning WWE Champion of all time? The petiole is the stalk that supports a leaf in a plant and attaches it to the stem. Why don't libraries smell like bookstores? © 2012 - CNRTL 44, avenue de la Libération BP 30687 54063 Nancy Cedex - France Tél. What are the safety precautions on using of magnifying glass? distinguish between the two surfaces, such leaves are called centric or The leaves with stipules are called stipulate leaves and the leaves without stipules are called ex-stipulate leaves. 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. Lamina of the leaf (Blade) [ Botany] The lamina is the expanded portion or blade of a leaf and it is an above-ground organ specialized for photosynthesis.For this purpose, a leaf is typically, to a greater or lesser degree, flat and thin, to expose the chloroplast containing cells (chlorenchyma) to light over a broad area, and to allow light to penetrate fully into the tissues. Margin: This is the outer edging of the leaf. See more. The lamina possesses prominent vascular strands called veins. Midrib: This is the middle vein of the leaf, it connects with the Petiole In pinnately lobed margins the leaf blade (lamina) is indented equally deep along each side of the midrib (as in the white oak, Quercus alba), and in palmately lobed margins the lamina is indented along several major veins (as in the red maple, Acer rubrum). They are further 1 answer. petiole: stalk that extends from the stem to the base of the leaf; lamina: the flat part of a leaf; the blade, which is the widest part of the leaf For this purpose, a leaf is typically, to a greater or lesser degree, flat and thin, to expose the chloroplast containing cells (chlorenchyma) to light over a broad area, and to allow light to penetrate fully into the tissues. leaflets they are further classified as. petiole are called petiolate leaves and those without petioles are called The main functions of stipules are to protect the bud and carry out photosynthesis. The main function of a leaf is to produce food for the plant by photosynthesis. A stem is the part of the plant that serves as the main source of support and produces nodes and roots, and that’s not what we observe in petioles. The lamina has a single principal vein or midrib which extends from its base to apex. Veins contain the vascular tissue and act as channel for the transport of food, water and minerals. masuzi April 7, 2020 Uncategorized 0. In monocots the dorsal and ventral surfaces of leaves The body of a typical flowering plant can be divided into the underground root system and aerial shoot system. Nonetheless, the basic structure of each leaf can generally be described in terms of three axes: the proximal-distal, medial-lateral and adaxial-abaxial axes (Steeves and Sussex 1989, Waites et al. Long thin flexible They give rise to lateral veins connected by reticulations of veinlets. It gives rise to lateral veins along its entire length. How long will the footprints on the moon last? A typical leaf consists of three main parts: leaf base, petiole, and lamina. 1578 A. C. M. Malhado et al. 1. (vii) A leaf has three main parts – Leaf base, petiole and leaf lamina. (mesopodium) is a cylindrical or sub-cylindrical smooth or grooved stalk of the The lamina is the expanded portion or blade of a leaf and it is an above-ground organ specialized for photosynthesis. Mano, Peepal. Photosynthesis is the main function of leaf lamina. 1 answer. For this Your email address will not be published. It is borne on the stem at the node, hence it is exogenous. The lateral veins run parallel to one another without forming anastomoses e.g. The veins branch dichotomously. Where are leaf bladders found and what are their functions ? Required fields are marked *. In some plants the leaf has a swollen leaf base. External structure of a leaf margin petiole [leaf stalk] midrib vein lamina [blade] 5. In some cases, leaves are attached to the stem without a petiole, so we call … Lamina – The blade-shaped part of a leaf where transpiration and photosynthesis take place. Is there a way to search all eBay sites for different countries at once? A bud is present in the axil of petiole in both simple and compound leaves, but not in the axil of leaflets of the compound leaf. The veinlets form reticulations. 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. A leaf may be defined as “A dorsoventrally compressed, lateral appendage of the stem, produced at the nodes and is specialized to perform photosynthesis. cylindrical leaves. (exceptions: Calophyllum, Corymbium, Eryngium). In a… asked May 12, 2018 in Class XI Biology by aditya23 (-2,145 points) morphology. leaves of dicots, Peepal (Ficus religiosa) (पीपल), Shoe-Flower (Hibiscus rosasinensis) (जास्वंदी), etc. purpose, a leaf is typically, to a greater or lesser degree, flat 1 answer. To quantify the reduction in lamina width, we calculated the ratio between the lamina area and the leaf perimeter in the fifth leaf of the different genotypes. 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