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List the struc tures found in a typical e udicot le a f. 01 Contrast nonwoody stems with woody stems. 02 Explain how se c ondary growth of a woody e udicot ste m oc curs a nd c ontrast spring wood with summer 03 wood. 04 List the thre e z ones of a e udicot root tip. ...
List the struc tures found in a typical e udicot le a f. 01 Contrast nonwoody stems with woody stems. 02 Explain how se c ondary growth of a woody e udicot ste m oc curs a nd c ontrast spring wood with summer 03 wood. 04 List the thre e z ones of a e udicot root tip. the main photosynthetic organ of plants, for intercepting light, leaves exchange gases with atmospher, diddipate heat , and defend themeselves from hervibores and pathogens. A. Leaf blade B. Leaf veins - contain vascular tissues C. Petiole - the stalk that joins the leaf to the node D. Stipules - in some plants, these are butterfly-like appendages found at the base of petioles Photosynthesis takes place in mesophyll tissue of leaves. The leaf is enclosed by epid ermal cells covered with a waxy layer, the cuticle. Water and solutes travel throughout the pla nt using the leaf veins, which contain xylem and phloem. A stoma is a n opening in the epidermis that permits the exchange of gases. A. Dermal Tissue i. Cuticle - waxy layer that covers the leaves ii. Epidermis - the cells that cover the leaf, upper and lower iii. Stomata- lenticels found in the leaves B. Vascular Tissue - enclosed in bundle sheath cells i. Phloem ii. Xylem C. Ground tissue leaf ground tissues are called mesophylls i. Mesophylls (a) Palisade Mesophyll - consists of one or more layers of elongated parenchyma cells on the upper part of the leaf most photosynthesis occurs (b) Spongy Mesophyll - below the palisade mesophyll, cells that are more loosely arranged, with air spaces where gas exchange happens A. Simple-has a single, undivided blade B. Compound - the blade consists of multiple leaflets A. Floral leaves (bracts) – in poinsettias B. Spines - in cacti C. Reproductive leaves - in Kalanchoes D. Insectivorous leaves - in pitcher plants E. Tendrils - in vines F. Storage leaves - in onion bulbs A. Floral leaves (bracts) – in poinsettias B. Spines - in cacti C. Reproductive leaves - in Kalanchoes D. Insectivorous leaves - in pitcher plants E. Tendrils - in vines F. Storage leaves - in onion bulbs a plant organ bearing leaves and buds, to elongate and orient the shoot in a way that maximizes photosynthesis by the leaves. A. Bud contains apical meristems that can produce new stems and leaves B. Axillary bud - bud at the angle of branch and stem C. Node - sites where leaves are attached D. Leaf (bud) scar - scar tissue where leaves (buds) are once attached E. Internode - spacing between two nodes F. Lenticels small holes in woody stems A. Pith-ground tissues at the center of a young woody plant B. Vascular cambium - meristem that produces the primary xylem and phloem * Vascular bundle - a bundle of phloem and xylem C. Cortex-ground tissues between the vascular bundle and the epidermis of a young woody plant D. Phelloderm is the secondary cortex D. Cork cambium - meristem that produces the cork cells E. Cork - cells that replace the cortex * Periderm - phelloderm, cork cambium and cork of plants *Bark - composed of secondary phloem, cork cambium, and the cork Nonwoody (herbaceous) eudicots have an epidermis, cortex tissue, vascular bundles in a ring, and an inner pith. Monocot stems have scattered vascular bundles and lack a distinct cortex or pith. Vasc ul arbun dl es arearran ged in a rin g Vascular bun dles are sc attered Woody stems have secondary growth due to vascular cambium, which produces new xylem and phloem every year. Cork replaces epidermis in woody plants. A woody stem has bark (containing cork, cork cambium, cortex, and phloem). Wood contains annual rings of xylem. A. Rhizomes in ginger B. Stolons/Runners - in strawberries and grasses (e.g. bamboo) C. Tubers - in potatoes D. Bulbs - in onions E. Corms - in gladioluses F. Cladophylls - in cacti G. Thorns in roses an organ that anchors a vascular plant in the soil, absorbs min erals and water , and often store s carbohydrates and other reserves A. Primary root - the first root of a plant B. Lateral root - root that branches off from primary root A monocot and a eudicot root tip has three zones : zone of ce ll d i vi si on (contains root apical meristem) protecte d by the root cap ; zone of elongat i on , whe re cells elongate and differentiate ; and zone of maturati on (has root hairs). Within the zone o f matur ation, a monocot and a eudicot root contains the followin g tissues. The vascular tissu e i n eudicot roots shows xylem arranged in a st ar shape , with p hlo e m b etween t h e arms of the xylem. In monocot roots, a central pith is sur rounded by a ring of vascular tissue containing alternating bundles of xylem and phloem. The endodermis regulates the entrance of minerals into vascular ti ssue. T he pericycle contains cells that can divide and form lateral root s. The cortex is made o f parenchyma cells that function in food storage , and the epidermis forms the outer layer and may possess root hairs. In monocot roots, a central pith is sur rounded by a ring of vascular tissue containing alternating bundles of xylem and phloem. The endodermis regulates the entrance of minerals into vascular ti ssue. T he pericycle contains cells that can divide and form lateral root s. The cortex is made o f parenchyma cells that function in food storage , and the epidermis forms the outer layer and may possess root hairs. A. Taproot system - one main vertical root, the taproot, which usually develops form the primary root and which helps prevent the plant from toppling B. Fibrous root system - a thick mat of slender roots spreading out below the soil surface A. Aerial roots - in orchids B. Buttress roots - in large tropical trees C. Stilt roots common in mangroves D. Prop roots in corn E. Pneumatophores - in mangroves F. Strangling roots - in figs G. Storage roots - in carrots H. Haustorial roots - in parasitic plants
