info on plant structure from Campbell's Biology textbook, ninth edition
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| 715232534 | Tissue | group of cells consisting of 1 or more cell types - together perform a specialized function | 0 | |
| 715232535 | Organ | -several types of tissues together that carry out particular functions | 1 | |
| 715232536 | 3 Basic Plant Organs | leaves, stems, roots | 2 | |
| 715232537 | Vegetative Growth | production of non-reproductive leaves, stems and roots | 3 | |
| 715232538 | Root | organ that anchors the vascular plant in the soil - absorbs minerals and water - stores carbohydrates | 4 | |
| 715232539 | Taproot | - one main vertical root - develops from an embryonic root - gives rise to lateral roots | 5 | |
| 715232540 | Lateral roots | -a.k.a branch roots | 6 | |
| 715232541 | adventitious roots | - grow in an unusual location such as roots arising from stems or leaves - occurs in many monocots | 7 | |
| 715232542 | fibrous root system | a mat of general thin roots spreading out below the soil surface - do not penetrate deeply, best adapted to areas of light rainfall or shallow soils | 8 | |
| 715232543 | Root hairs | - on root tips - increase the surface area of the root enormously - main fxn: absorption | 9 | |
| 715232544 | Specialized root adaptations | Prop roots, storage roots, buttress roots, "strangling" aerial roots, & pneumatophores | 10 | |
| 715232545 | Prop roots | -support the tall top-heavy trees in sandy soils | 11 | |
| 715232546 | Storage roots | store food (starch) and water in their roots | 12 | |
| 715232547 | Buttress roots | give architectural support to the trunks of trees in the tropics | 13 | |
| 715232548 | "Strangling" aerial roots | - the strangler fig germinates in the branches of the tall trees - they send snakelike roots that wrap around the host trees - the host tree eventually dies from shading of the fig leaves | 14 | |
| 715232549 | Pneumatophores | -aka air roots - Ex: mangroves - roots project above the water line, enabling the roots to obtain oxygen, which is lacking in the watery mud | 15 | |
| 715232550 | Stem | -organ that raises or separates leaves, exposing them to sunlight - raise reproductive structures for fruit and pollen dispersal - consists of nodes and internodes | 16 | |
| 715232551 | Nodes | points at which leaves are attached | 17 | |
| 715232552 | Internodes | stem segments between nodes | 18 | |
| 715232553 | Axillary bud | - in the upper angle(axil) formed by each leaf an the stem - can form a lateral shoot (a branch) | 19 | |
| 715232554 | Apical bud | - aka terminal bud - area where most of the growth of a shoot begins - composed of developing leaves and a compact series of nodes and internodes | 20 | |
| 715232555 | Apical dominance | - the inhibition of axillary buds by an apical bud - removing the apical bud stimulates the growth of axillary buds | 21 | |
| 715232556 | Modified Stem Adaptations | - Rhizomes, Bulbs, Stolons, and Tubers | 22 | |
| 715232557 | Rhizomes | - a horizontal shoot that grow just below the surface - vertical shoots emerge from axillary buds on the rhizome | 23 | |
| 715232558 | Bulbs | - consist of enlarged bases of leaves that store food - Ex: onion | 24 | |
| 715232559 | Stolons | - horizontal shoots that grow along the surface - enable a plant to reproduce asexually Ex: strawberries | 25 | |
| 715232560 | Tubers | -Ex: potatoes - enlarged ends of stolons or rhizomes specialized for storing food | 26 | |
| 715232561 | Leaf | main photosynthetic organ - consist of a blade & petiole | 27 | |
| 715232562 | Blade | -flattened photosynthetic part | 28 | |
| 715232563 | Petiole | - the stalk - joins the leaf to the stem at a node - grasses & many monocots lack these | 29 | |
| 715232564 | Veins | vascular tissue of leaves - monocots - parallel veins -eudicots- branching network of veins | 30 | |
| 715232565 | Simple Leaf | single undivided blade - some can be deeply lobed | 31 | |
| 715232566 | Compound leaf | blade consists of multiple leaflets - a leaflet has no axillary bud at its base | 32 | |
| 715232567 | Doubly compound leaf | each leaflet is divided into smaller leaflets Ex: fern | 33 | |
| 715232568 | Advantage of compound leaves | - withstands strong wind with less tearing - can confine some pathogens | 34 | |
| 715232569 | Leaf Adaptations | tendrils, spines, storage leaves, reproductive leaves, and bracts | 35 | |
| 715232570 | Tendrils | forms a coil that brings the plant closer to a support structure | 36 | |
| 715232571 | Spines | - on cacti - provide some shading and protection | 37 | |
| 715232572 | Storage Leaves | succulents- storage water in their leaves | 38 | |
| 715232573 | Reproductive leaves | some succulents produce adventitious plantlets which fall off the leaf and take root in the soil | 39 | |
| 715232574 | Bracts | ex: Poinsettia - brightly colored leaves that attract pollinators - often mistaken for petals | 40 | |
| 715283634 | Dermal Tissue System | plant's outer protective covering -consists of epidermis, cuticle, and periderm - 1st line of defense against of pathogens and physical damage | 41 | |
| 715283635 | Epidermis | - layer of tightly packed cells in nonwoody plants | 42 | |
| 715283636 | Cuticle | waxy coating on the epidermal surface - helps prevent water loss - in leaves and most stems | 43 | |
| 715283637 | Periderm | - in woody plants, it replaces the epidermis in older regions of stems and roots | 44 | |
| 715283638 | Trichomes | hairlike outgrowths of the shoot epidermis - reduce water loss and reflect excess light - major fxn: provide defense against insects by secreting sticky fluids to stop insects from eating them | 45 | |
| 715283639 | Vascular tissue system | - consists of xylem and phloem - carries out long distance transport of materials between roots and shoots | 46 | |
| 715283640 | Xylem | - conducts water and minerals up from roots to shoots | 47 | |
| 715283641 | Phloem | - transports sugars from where they are made to where they are needed | 48 | |
| 715283642 | Stele | - the vascular tissue of a root or stem | 49 | |
| 715283643 | Ground Tissue system | - neither part of the dermal or vascular tissue - two types: pith and cortex | 50 | |
| 715283644 | Pith | ground tissue that is internal to the vascular tissue | 51 | |
| 715283645 | Cortex | ground tissue that is external to the vascular tissue | 52 | |
| 715283646 | Plant Cell Types | Parenchyma, Collenchyma, Sclerenchyma, Xylem and Phloem | 53 | |
| 715283647 | Parenchyma Cells | - mature cells have primary walls, most lack secondary walls - large central vacuole - perform most metabollic fxns of the plant - photosynthesis occurs in chloroplast of parenchyma cells - fleshy fruits composed of these cells - store starch in roots and stems - can grow an entire plant from one of these cells | 54 | |
| 715283648 | Collenchyma Cells | - support younger parts of the plant shoot - elongated and have thicker primary walls - ex: the strings of celery - provide flexible support w/o restraining growth - living at maturity | 55 | |
| 715283649 | Sclerenchyma Cells | - fxn in support - more rigid than collenchyma cells - contain lignin - dead at maturity- cannot elongate 2 types of these cells: sclereids and fibers | 56 | |
| 715283650 | Sclereids | - boxier than fibers & irregular shape - used for support and strengthening - very thick secondary walls - give nut shells their hardness | 57 | |
| 715283651 | Fibers | long, slender and tapered - used to make linens fxn: strength and support | 58 | |
| 715283652 | Xylem | - transports minerals and water - two types of cells : tracheids & vessel elements | 59 | |
| 715283653 | Tracheids | - long, thin and tapered - water moves through pits, so it doesn't have to cross the thick secondary walls - dead at maturity - all vascular plants have these - walls have lignin | 60 | |
| 715283654 | Vessel Elements | - wider and shorter than tracheids - lignified walls & dead at maturity - found mainly in angiosperms - aligned end to end forming miropipes called vessels, with the end walls having perforation plates that enable water to flow freely between them | 61 | |
| 715283655 | Phloem | -moves sugar throughout the plant - alive at maturity - 2 types of cells: sieve tube elements and companion cells | 62 | |
| 715283656 | Sieve Tube Elements | - transports nutrients in chain of sieve tubes - lack a nucleus, ribosomes, vacuole, and cytoskeletal elements --> allows nutrients to pass more easily - end walls of the sieve tubes are seperated by the sieve plates that have pores to facilitate flow through the sieve tubes | 63 | |
| 715283657 | Companion cells | - non- conducting cell found along side the sieve tube elements - connected via plasmodesmata - help load sugars into the sieve tube elements | 64 | |
| 715283658 | Indeterminate Growth | - process of growth that continues all throughout a plant's life | 65 | |
| 715283659 | Meristems | areas of undifferentiated growth that divide and lead to new cells that elongate - 2 types: apical and lateral meristems | 66 | |
| 715283660 | Apical meristems | - located at the tips of roots and shoots and in axillary buds of shoots - provide additional cells that enable growth in length | 67 | |
| 715283661 | primary growth | growth in length in the vertical direction - allows roots to extend in the soil and shoots to increase their exposure to light | 68 | |
| 715283662 | Secondary growth | growth in thickness - caused by lateral meristems - occurs in roots and woody stems - rarely seen in monocots | 69 | |
| 715283663 | Lateral meristems | - called vascular and cork cambiums | 70 | |
| 715283664 | Vascular cambium | adds layers of vascular tissue called the secondary xylem and phloem | 71 | |
| 715283665 | Cork cambium | replaces the epidermis with thicker periderm - adds secondary dermal tissue | 72 | |
| 715283666 | Annuals | - complete life cycle( germination to flowering to seed production to death) in a year or less | 73 | |
| 715283667 | Biennials | - require two growing seasons to complete thier life cycle, flowering only in the second year | 74 | |
| 715283668 | Perennials | - live many years and include trees, shrubs, and grasses | 75 | |
| 715771956 | Root cap | - covers the root tip - protects the apical meristem as the root pushes through the soil - secretes polysaccharide slime to lubricate soil around the root tip | 76 | |
| 715771957 | Zones of Growth in a Root | Zones of Cell division, elongation, and maturation (differentiation) | 77 | |
| 715771958 | Zone of Cell Division | - includes the root apical meristem - new root cells are produced here | 78 | |
| 715771959 | Zone of Elongation | - most of the growth occurs here - cells elongate, pushing the root tip further into the soil | 79 | |
| 715771960 | Zone of Differentiation | - cells complete their formation into specialized functioning cells and become distinct cell types | 80 | |
| 715771961 | Root Cross section of a Eudicot | - vascular tissue(xylem and phloem) is in the center in the shape of an "X" | 81 | |
| 715771962 | Root Cross section of a Monocot | - vascular tissue is in the center but more spread out in a circle with a core of parenchyma cells in the very center | 82 | |
| 715771963 | Endodermis | -innermost layer of the cortex - surrounds the vascular cylinder - regulates passage of substances from the soil into the vascular tissue | 83 | |
| 715771964 | Pericycle | - where lateral roots grow from - outermost cell layer in the vascular cylinder - a ring just inside the endodermis | 84 | |
| 715771965 | Leaf primordia | -finger like projections on either side of the apical meristem in a shoot tip | 85 | |
| 715771966 | Branching | - part of shoot primary growth - arises from the activation of axillary buds - the closer the axillary bud is to an active apical bud, the more inhibited it is | 86 | |
| 715771967 | Lateral shoots | - develop from axillary bud meristems on the stem's surface and disrupt no other tissues | 87 | |
| 715771968 | Cross section of a Eudicot stem | - vascular tissue is arranged in a ring - xylem is on the inside and phloem on the outside | 88 | |
| 715771969 | Cross section of a Monocot stem | vascular bundles are all scattered throughout the stem - don't graph well - look like a monkey face | 89 | |
| 715771970 | Stomata | - located on the epidermis of leaves - allow gas exchange (CO2 and O2) between leaf and air - major avenue for evaporative water loss - surrounded by 2 guard cells | 90 | |
| 715771971 | Guard Cell | - regulate the opening and closing of the stomata pore | 91 | |
| 715771972 | Mesophyll | ground tissue of a leaf - in between the upper and lower epidermis layers 2 layers: palisade and spongy mesophyll | 92 | |
| 715771973 | Palisade mesophyll | - has parenchyma cells specialized for photosynthesis - upper layer of mesophyll | 93 | |
| 715771974 | Spongy mesophyll | - parenchyma cells are arranged loosely with air spaces so that oxygen can circulate around | 94 | |
| 715771975 | Bundle sheath | - parenchyma cells that surround the vein of vascular tissue in a plant leaf | 95 | |
| 715771976 | Vascular cambium | - adds layers of secondary xylem to its interior and secondary phloem to its exterior--> thickens roots and stems - the layers of xylem (wood) accumulates over the years = tree rings -older secondary xylem usually gets sloughed off-does not accumulate like the xylem in a tree | 96 | |
| 715771977 | Vascular rays | - radial files of parenchyma cells that connect the secondary xylem and phloem -fxn: aid in wound repair, store carbs, and move water and nutrients between the xylem & phloem | 97 | |
| 715771978 | Bark | - everything exterior to the vascular cambium - secondary xylem, cork, cork cambium | 98 | |
| 715771979 | Periderm | cork and the cork cambium | 99 | |
| 715771980 | Heartwood | - layers of secondary xylem that no longer transports water and minerals - closer to the center of a stem or root - darker colored than sapwood | 100 | |
| 715771981 | Sapwood | - newest, outer layers of secondary xylem that still transport water and minerals | 101 | |
| 715771982 | Asymmetrical cell division | - one daughter cell receives more cytoplasm than the other during mitosis - how guard cells form around the stomata | 102 |
