CH 34 Plants Form and Function

gymnosperm

a vascular seed pkant with no flowers or fruits

angiosperm

flowering plants that can also have fruits

eudicot

a monophyletic group cosnsiting of most of the angiosperms that have two embryonic seed leaves that include taproots, branched leaf veins, and floral organs in groups of 4 or 5

monocot

a monophyletic group consisiting of angiosperms that have one embryonic seed leaf also fibrous roots, parallel leaf veins, and petals in groups of three

phenotypic plasticity

within species variation in morphology because of variable environmental conditions within species variation

totipotency

ability of a cell to divide indeterminately

organ

a group of different tissue types that work together to perform a distinct function

roots

plant organ that anchor plant, provide water and nutrients, storage, recieves energy from shoot system, and mutualisms

anchor roots

roots that support plant attachment to walls and surfaces e.g. ivy

prop roots

roots that support stem and rest of plant e.g. corn

storage roots

roots that store carbon and starch in taproot e.g. carrots, beats

stem

plant organ that support leavs and flowers and function as transport, communication, and storage

water storage structures

modified stems (such as spikes on cacti) that are used for water storage

stolons

modified stem runners that create new individuals with above ground horizontal stems

rhizosomes

modified stems that store carbohydrates and grow horizontal underground

tubers

modified stem structures that are swollen rhizosomes that store carbohydrates like starch (potato)

thorns

modified stem structures that are used for protection

leaf

plant organ formed of blade and petiole that primary serve for photosynthesis

bulbs

modified leaf structures for storage of food (such as an onion)

succulent leaves

modified leaf structure for water storage

tendrils

modified leaf structures for signalling and growth (peas)

floral mimics

modified leaf structures for reproduction and pollinators

traps

modified leaf structures for nutrition and digestion like venus flytrap

spines

modified leaf structures for protection and light reflection

primary cell wall

structural cell wall of plant cells that consist of cellulose, crosslink hemicellulose structures bound together surrounded by pectin

secondary cell wall

hard and rigid interior cell wall of plant cells that consist of plasmodesmata gap connections with a middle lamella that is lignin dispersed

middle lamella

gelatinous polysacchride pectin that glues cell walls together between plant cells

lignin

large polymer that fills space between cellulose and hemicellulose in secondary cell wall

tissues

group of similar cells organized into a functional unit

dermal tissue

tissue system that form epidermis and mainly lacks chloroplasts primarily for protection

epidermis

outer tissue layer that secretes wax to form cuticle

stomatal guard cells

cells that help anchor stomata

trichomes

hairlike appendages that are made of specialized epidermal cells that work for protection, light reflection, etc.

root hairs

epidermal structures where water and nutrients enter plants at the roots

ground tissue

tissue system that consists of all tissue between dermal and vascular tissue where carbohydrate storage occurs

parenchyma

relatively large ground tissue cells with only primary cell wall used for storage and have large vacuoles

collenchyma

ground tissue cells with only a primary cell wall but thickening on the edges from cellulose and provides structural support but is somewhat flexible in stems

sclerenchyma

ground tissue cells that are lignified that are dead at maturity and have secondary cell walls

fibers

extremely elongated sclerenchyma cells that function for structural support and vascular tissue

sclereids

relatively short variable sclerenchyma cells that form nut shells, pear grains, and is protection

vascular tissue

tissue system used for transport throguhout plant

xylem

vascular tissue that consists of water and nutrient conducting cells that are lignified and dead at maturity with secondary cell walls, includes fivers and parenchyma cells as well as forms wood and has unidirectional flow

tracheids

water conducting cells in all vascular plants (gymnosperms and angiosperms) that has pits

vessel elements

water conducting cells in only angiosperms that have pits and perforations