(6) Plant Cells and Plant Transport Review

• covers the surface of plant
• composed of single layer of cells called epidermis
• cells are cube shaped and tightly packed together
• covered by a layer of wax called the cuticle
• has cell extension (root hairs)

xylem and phloem

• tracheids
• vessels

• type of xylem tissue found in all vascular plants
• dead at functional maturity
• has fusiferm shape that allows xylem to move
• supports plants and conducts xylem sap
• has primary and secondary cell walls

• type of xylem tissue
• found in angiosperms
• dead at functional maturity
• not good for support
• has primary cell walls
• more efficient at transfer of xylem sap

• sieve tube memeber
• companion cells

• type of phloem tissue
• alive at functional maturity
• transports xylem sap
• no nuclei, ribosomes, or vacuole
• cannot make protein

• type of phloem tissue
• lies along sieve tube member/element
• connects with plasmodesmota
• has nuclei and ribosomes
• gives protein to sieve tube members

fills in space between dermal and vascular tissue, location of metabolic pathways; where photosynthesis occurs

• parenchyma
• collenchyma
• sclerenchyma

• type of ground tissue cell
• alive at functional maturity
• least specialized=can differentiate
• has thin primary cell wall
• never has secondary cell wall

• type of ground tissue cell
• alive at functional maturity
• thick primary cell wall
• no secondary cell wall
• supports young growing part of plant

• type of ground tissue cell
• dead at functional maturity
• has primary and secondary cell wall
• supports older parts of the plant
• 2 types of cells: fibers and sclerids

lateral meristems

• product of apical meristem
• increases girth
• vascular cambrian creates secondary xylem and phloem
• cork cambrien

• forms cork=parenchyma cells
• filled with suberin
• cells divide and produce cork
• prevents evaporation of water and protects from bugs

• weak, only important n smaller plants
• solutes are actively transported from the soil into the xylem which causes water potential to lower
• water potential of stele is lower than the cortex in the soil
• lower wate potential is what causes water to move in because water moves from high to low
• ex. of root pressure-guttation

energy of sun evaporates water from leaves, creating energy to pull the xylem sap up

• solar powered so no ATP
• the evaporation provides energy to pull the xylem sap up the plant (pulls minerals and water from the soil to the leaves, also cools them)

• water molecules stick together because of H bond
• as rate of evaporation increases, changes meniscus curve (affects tension)

• formed by transpiration
• a meniscus forms at junction of cells on a hot dry day: rate of transpiration will be higher, which creates tension