LECTURE PRESENTATIONS For CAMPBELL BIOLOGY, NINTH EDITION Jane B. Reece, Lisa A. Urry, Michael L. Cain, Steven A. Wasserman, Peter V. Minorsky, Robert B. Jackson Chapter 35 Plant Structure, Growth, and Development Lectures by Erin Barley Kathleen Fitzpatrick Overview: Are Plants Computers? Romanesco grows according to a repetitive program The development of plants depends on the environment and is highly adaptive 1
Concept 35.1: Plants have a hierarchical organization consisting of organs, tissues, and cells 특정세포로이루어진조직들이기관을형성 조직 : 하나, 혹은그이상의종류의세포가모여서특정기능을수행하는세포그룹 기관 : 여러조직으로이루어져특정기능을수행 The Three Basic Plant Organs: Roots, Stems, and Leaves Basic morphology of vascular plants: 지하부위와지상부위에서필요물질을흡수 세개의주요기관 : 뿌리, 줄기, 잎 수분과미네랄은지하부위에서뿌리를통해 이산화탄소와빛은지상부줄기와잎에서 뿌리와줄기는상호의존적 two major groups of angiosperm: monocots and eudicots 2
Roots functions: Anchoring the plant Absorbing minerals and water Storing carbohydrates taproot system: most eudicots and gymnosperms A taproot, the main vertical root Lateral roots, or branch roots, that arise from the taproot fibrous root system: most monocots Adventitious roots that arise from stems or leaves Lateral roots that arise from the adventitious roots root hairs: 표면적을증가시켜수분과양분의흡수에적절 3
다양한기능으로적응된뿌리들 Stems consists of An alternating system of nodes, the points at which leaves are attached Internodes, the stem segments between nodes axillary bud( 곁눈 ): a structure that has the potential to form a lateral shoot, or branch apical bud (terminal bud, 끝눈 ): located near the shoot tip and causes elongation of a young shoot Apical dominance ( 정단우성 ): maintain dormancy in most axillary buds 4
다양한형태의줄기 rhizomes( 지하줄기 ), bulbs( 비늘줄기 ), stolons( 기는줄기 ), tubers( 덩이줄기 ) Leaves 주광합성기관 납작해진 blade( 엽신 ) 과 petiole( 엽병 ) 으로구성 Monocots 과 eudicots 에서의 veins( 잎맥 ) 배열의차이 Most monocots: parallel veins Most eudicots: branching veins In classifying angiosperms, taxonomists may use leaf morphology as a criterion 5
Simple leaf Axillary bud Petiole Compound leaf Leaflet Doubly compound leaf Petiole Axillary bud Petiole Axillary bud Leaflet 다양한기능을수행하는변형된잎 6
Dermal, Vascular, and Ground Tissues 식물의기관 : dermal( 표피조직 ), vascular( 관다발조직 ), ground tissues( 기본조직 ) 을가짐. 각조직은식물전체를연결하는 tissue system( 조직계 ) 을형성 dermal tissue system 초본식물 : epidermis( 표피 ) 로구성됨. A waxy coating called the cuticle helps prevent water loss from the epidermis 목본식물 : 오래된줄기와뿌리에서 periderm( 주피 ) 이표피를대체 트라이콤 : outgrowths of the shoot epidermis, helps with insect defense 7
vascular tissue system: long-distance transport of materials between roots and shoots Xylem( 물관부 ), phloem( 체관부 ) Xylem conveys water and dissolved minerals upward from roots into the shoots Phloem transports organic nutrients from where they are made to where they are needed Stele( 중심주 ): 뿌리와줄기의관다발조직 피자식물 : the stele of the root is a solid central vascular cylinder. 줄기에서는 divided into vascular bundles, strands of xylem and phloem ground tissue system vascular tissue 안쪽의 pith( 수 ), vascular tissue 바깥쪽의 cortex( 피층 ) includes cells specialized for storage, photosynthesis, and support Common Types of Plant Cells The major types of plant cells are: Parenchyma( 유세포 ) Collenchyma( 후각세포 ) Sclerenchyma( 후벽세포 ) Water-conducting cells of the xylem Sugar-conducting cells of the phloem 8
Parenchyma Cells Mature parenchyma cells 세포벽이얇고유연 2 차세포벽이없음. the least specialized 대부분의물질대사기능을수행 세포분열과분화능을가지고있음. Bioflix: Tour of a Plant Cell 9
Collenchyma Cells 다발로모여줄기의어린부분을지탱 두껍고불균등한세포벽을가짐. 2 차세포벽이없음. 생장을방해하지않는정도의유연성을갖는지지기능수행 Sclerenchyma Cells 리그닌이축적된 2차세포벽을가지고있어매우단단함. dead at functional maturity There are two types: Sclereids( 보강세포 ): short and irregular in shape and have thick lignified secondary walls Fibers( 섬유 ) are long and slender and arranged in threads 10
Water-Conducting Cells of the Xylem two types: tracheids( 헛물관 ), vessel elements( 물관요소 ), dead at maturity 헛물관 : 모든관다발식물의물관에서발견됨. 물관요소 : 대부분의속씨식물과일부의겉씨식물, 끝과끝이연결되어 vessel 이라는긴관을형성 Sugar-Conducting Cells of the Phloem Sieve-tube elements( 체관요소 ): alive at functional maturity, though they lack organelles Sieve plates( 체판 ): the porous end walls companion cell: sievetube element 옆에존재, 핵과리보조옴이자신뿐아니라체관요소에관여 11
Concept 35.2: Meristems generate cells for primary and secondary growth Indeterminate growth: A plant can grow throughout its life determinate growth: Some plant organs cease to grow at a certain size Meristems( 분열조직 ): perpetually embryonic tissue and allow for indeterminate growth Initials(stem cells): which remain in the meristem Derivatives: become specialized in mature tissues Apical meristems( 정단분열조직 ): at the tips of roots and shoots and at the axillary buds of shoots Primary growth: 정단분열조직에의한뿌리와줄기의길이생장 Shoot tip (shoot apical meristem and young leaves) Axillary bud meristem Vascular cambium Cork cambium Primary growth in stems Epidermis Cortex Primary phloem Primary xylem Pith Lateral Secondary growth in stems meristems Cork cambium Periderm Cortex Primary phloem Root apical meristems Pith Primary xylem Secondary xylem Secondary phloem Vascular cambium 12
Lateral meristems( 측생분열조직 ): secondary growth 라는목본식물의부피생장 vascular cambium( 관다발형성층 ): secondary xylem(wood) 과 secondary phloem 형성 cork cambium: 표피를주피로대체 (thicker and tougher) 목본식물의경우, primary growth and secondary growth 는동시에다른위치에서 Flowering plants can be categorized based on the length of their life cycle Annuals complete their life cycle in a year or less Biennials require two growing seasons Perennials live for many years 13
Concept 35.3: Primary growth lengthens roots and shoots Primary growth produces the parts of the root and shoot systems produced by apical meristems Primary Growth of Roots Video: Root Growth in a Radish Seed (Time Lapse) 14
Primary Growth of Roots Root cap( 뿌리골무 ): 뿌리정단부를감싸뿌리정단분열조직을보호 Growth occurs just behind the root tip, in three zones of cells: Zone of cell division Zone of elongation Zone of differentiation, or maturation The primary growth of roots produces the epidermis, ground tissue, and vascular tissue In most eudicots, the xylem is starlike in appearance with phloem between the arms In many monocots, a core of parenchyma cells is surrounded by rings of xylem then phloem 15
ground tissue: 대부분유세포, vascular cylinder 와표피사이의피층 endodermis( 내피 ): 피층의가장안쪽세포층, 토양으로부터관다발기둥까지물질운반을조절 Lateral roots arise from within the pericycle, the outermost cell layer in the vascular cylinder Primary Growth of Shoots A shoot apical meristem is a domeshaped mass of dividing cells at the shoot tip Leaves develop from leaf primordia( 잎원기 ) along the sides of the apical meristem Axillary buds( 측아 ) develop from meristematic cells left at the bases of leaf primordia 16