PLANTS plant cell - Numilogexcerpts.numilog.com/books/9782764408865.pdf8 plant cell Smallest living...
Transcript of PLANTS plant cell - Numilogexcerpts.numilog.com/books/9782764408865.pdf8 plant cell Smallest living...
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plant cellSmallest living structure and the constituent element of all vegetables; it varies in size and shape depending onits function.
cell wallStiff exterior surface of the cytoplasmicmembrane that gives the cell its shape.
ribosomeSmall structure, occasionally attached to theendoplasmic reticulum; it generates proteinsessential to the formation and functioning of
living things.
chloroplastSmall structure, containing a green
pigment called chlorophyll, which absorbssolar energy and uses it to produce
glucose, the vegetable’s food.
cytoplasmClear gelatinous substance
surrounding the various cellularstructures.
lipid dropletSmall sac filled with essential fatty
acids that are produced by the cell andstored for food.
cell membraneCasing that covers the cell’s
cytoplasm; it acts as a filter, controllingthe passage of certain substances in
and out of the cell.
vacuoleSpherical cavity containing water,
waste and various substances requiredby the cell.
Golgi apparatusOrganelle composed of a series of pockets
that receive proteins produced by theribosomes and either transport them outside
the cell or to other organelles.mitochondrion
Ovoid organelle that produces theenergy necessary for cell activity.
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plasmodesmaPerforations in the membranesallowing two adjacent cells toexchange cytoplasm.
endoplasmic reticulumInterconnecting tubes allowingsubstances to be transported within thecell or between the cell and its exteriorenvironment.
porePerforations in the nuclear envelopeallowing for exchanges between thecytoplasm and the nucleus.
nucleusOrganelle containing a cell’s genes andcontrolling its activities.
nuclear envelopeA double-layered membrane envelopingthe nucleus.
nucleolusSmall spherical body located inside thenucleus, within which the ribosomes, orprotein-synthesizing structures, areproduced.
starch granuleConcentric layers of starch produced
by the cell and stored for food.
leucoplastSmall colorless structure that producesand stores starch, the vegetable’s food.
plant cellP L A N T S
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structure of a lichen
lichenVegetable formed from the symbiotic association of an alga and a fungus.
apotheciumReproductive organ of the fungus thatis a part of the lichen.
thallusLichen’s main structure formed by the
imbrication of fungal filaments andalga cells.
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examples of lichensThere are more than 20,000 species of
lichen, found growing out of the soil, ontree trunks or on rocks; they grow in all
climatic zones.
fruticose lichenLichen whose thallus resembles a
small tree; it is attached to its substrateat a single point.
crustose lichenLichen whose thallus forms a crust that
is firmly attached to its substrate.
foliose lichenLichen whose thallus resembles leaves
or lobes that are loosely attached totheir substrate and can be easily
removed.
lichenP L A N T S
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mossFlowerless vegetable, usually small in size, that grows in large tightly packed tufts to create a veritable softcarpet.
leafPart of the moss originating at thestem, especially adapted to capturelight, perform photosynthesis andabsorb water.
stemMain part of the moss from which the
leaves spiral outward; it can be uprightor flat.
rhizoidRootlike filament enabling the moss toanchor itself to its substrate andabsorb water and mineral salts.
capsuleHollow structure that manufactures
spores, small seeds used inreproduction; it has a cover that opens
to release the mature spores.
stalkLong slender axis that supports the
capsule, enabling it to absorbnutrients.
structure of a moss
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examples of mossesThere are more than 13,000 species of
moss; they generally grow in damp soil,on rocks or tree trunks and occasionally
in fresh water.
common hair cap mossGround moss with an erect stem and stiff
leaves that grows in tufts, mostly inwooded areas; the capsule emerges from
the end of a very long stalk.
prickly sphagnumBog moss that has no rhizoid and rarely
bears a capsule; it has a high watercontent and its decomposition helps to
form peat.
mossP L A N T S
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algaFlowerless vegetable that usually lives in aquatic environments; it produces oxygen and is at the base of thefood chain.structure of an alga
receptacleEnlarged part, generally located at the
tip of a frond, holding the alga’sreproductive organs.
thallusAlga’s main structure, with
undifferentiated stem and leaves.
aerocystSmall gas-filled bladder containingnitrogen and oxygen; it is located in
the thallus of some algae and providesbuoyancy.
midribProjection running the length of thethallus or fronds of certain algae.
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red algaRed-pigmented alga that generally lives insalt water and at greater depths than otheralgae; there are 4,000 species of red algae.
green algaAlga often found in freshwater, but also
in seas and some nonaquaticenvironments; there are 6,000 species
of green algae.
laminaPart of the thallus that is shaped like ablade; it is quite wide and looks like aleaf.
examples of algaeMore than 25,000 species of algae live inaquatic environments or in some regions
with damp soil; they vary in size frommicroscopic to 60 ft in length.
brown algaBrown-pigmented alga that usuallylives in the sea, often in cold water;
there are more than 1,500 species ofbrown alga.
hapteronSmall, occasionally branched disk,located at the base of certain thalli,
enabling their attachment to asubstrate.
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alga