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Primary growth

Vertical growthProduces primary plant body, parts of the roots and shoot systems produced by apical meristemsHerbaceous plants the entire plant body is a primary plant body

2 differences: 1 is how it grows in roots/shootsRootsRoot is covered root cap to protect cells and secretes slime made of polysaccharide to lubricatewhen cells grow down into soilRoot tips there are cell division, elongation and maturationThe 3 zones they grade together, no sharp differenceZone of cell division includes the apical meristems, root cap, and all of derivitivesZone of elongation the root cells elongating downwardsZone of maturation complete differentiationRoots have vascular stele in the middle consisting of xylem of phloemPhloem is in bbetween xylem which is the cyldiner > in uticots

In monocots its in ringsOtuside the center is cortex parenchima cellsEndodermis provides boundary between the cylinder and the cortex so no leakingLateral roots grow from the pericycle which comesfor the endodermis and push through the celland into the epidermis and branches

ShootsPrimary growth starts from top of apical is from the top, pushes upDomed shaped on terminal budLeaves come out as leaf primordiaArise from the sidesInternode is the space inbetween growing partAnd the node is where branch growsDuring the leaf primordias growth the apical meristem leaves behind undefereitnated cells forlater division as auxiliary buds use for lateral growth (preparing for secondary growth)

Tissue Organization of StemsLateral shoots arise from preexisting auxlairy budsThey have different vascualar bundlesAll same except in zone of transition which disgintuashes the different steals, above the soilVascualr tissues in stems in gymnosperms and eudocots, the xylem faces the pithThe phloem faces outward/cortexIn monocots have no organization are scatteredIn both the ground tissue it consists of parenchyma cells, fiber cells beneath the epidermis

T.O of LeavesStamata and space between each cells and guarded by guard cellsMager avenus for transportation, transpirtation, and gas exchangeParenchama on the epidermis is elongated and tightly pack- plaside mesophyll and the spongeyis loosely packed for vascular tissues can go through/gas exchange

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Vascular tissues of leaf is leaf trace and is continuous stele of the steamEach vein is protected by bundle sheath

35.4 Second Growth in woody plantsGrowth in thickness by later meristems dependoing on where it is, if its the shoot it would be an

axil bud and root it would be a pericycle budProduces secondary plant body and that constists of any tissues from the cambiumsVascular cambium adds secondary xylem and phloemCork cambium tough thick covering consisiting of crock cellsOccur simotaneously in different regions2nd growth occurs in older parts in woody plants which is why its thinner at top and helps withsupport

Vascular cambium and secondary vascular tissueDevelops from dedeffrirented cells and the cambium comes in bandsForms in layer between primary xylem/phloem

Adds xylem to inner and phloem to outer to thickenForms in segmentsEventually becomes cylinderVascular cambiam creates fusiform and ray initialsFusiform initials produce cells that grow vertically for transport (produced in rings)Produces tapered elongated traches, vessels, fibers, sieve tubesRay initials grow perpendicular to fusiform, horizontalProduced in xylem and phloem (rays)Fusiform are living avenus for storage and transportSecondary xylems are mainly tracheids, vessel elements, and sieve tube and they are dead atfunctional maturityGymnospemrs mostly tracheirdsAngospemrs its all of itIf vascular cambium develops in Early springs its earlywood and if it developes in winter itslatewood and earlywood transports more waterAs xylem gets older the center is called heartwood, dosnt function that much but trees make itstronger for supportSome trees are hallow in middle bc they can function without heartwoodYounger layers are calld sapwood bc theys till transport sap

Epidermis moves outward bc it gets older then it falls off and gets replaced with periderm andthe cork cambium is like vascular cambium and its outside the stele and towards outside of thestemCork cambium produces cork cells outside and they harden bc of waxy substance called subrinOn periderms there are lenticells and thats so it exposes cork cells that are actually doing gasexchange but most of gas exchange occurs in youngest roots at bottomCorck cambium gets shed off so it continues to grow and make a new cork cambium

35.5If plane is vertical across it grows into line

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But if its 3 dimension it grows in cubesPlants have platcicidy and change ccidelant and mentatliyning easier and cells can dedifrentiatedCell fate is based on epidermis and on relative positional formationDifferent phasesPass through juevinile, adult vegatigive, adult reporudctiive

Occurs in shoot apical meristemstypes of sepal, pedals, stamen, carpels from flowering

A- sepels, pedalsB- pedals, stamensC- stames and carpels

Overlaps so it can create more if one gene is turned off