Plant Physiology

meristem

undifferentiated tissue from which new cells are formed, as at the tip of a stem or root

Apical meristem

Primary meristem, increase in height (roots grow down, shoots grow up)

Lateral Meristem

Secondary meristem; increases the girth

Ground Tissue

photosynthetic tissue, storage of starch, parenchyma cells

Dermal Tissue

Protection; epidermal and cork

Xylem

the supporting and water-conducting tissue, consisting primarily of tracheids and vessels; unidirectional; transports dissolved minerals too

phloem

tissue that conducts synthesized food substances (dissolved sucrose) to parts where needed; consists primarily of sieve tubes; bidirectional

middle lamella

lipid-like glue that holds plant cells together; composed of pectin

Plasmodesmata

cytoplasmic bridge; pores between cells for transport

Root hairs

increase the surface area for water and mineral absorption

secondary cell wall

Composed of ligin; only in plants specialized for support, protection, or water conduction;

protoplast

all of a plant cell minus the cell wall

pit

pore in the secondary wall