Radience

Plant Structure

Science

apical meristem

the cells at the tips of roots and stems, as they divide, the root and stem lengthen
apical meristem Simple Definition

collenchyma

an flexible plant cell with unevenly thick walls, it forms supportive tissue in plants
collenchyma Simple Definition

companion cell

a nucleated cell that helps to transport substances through the sieve cells of the phloem
companion cell Simple Definition

cork cambium

meristem tissue that produces the protective outer layer of roots and stems
cork cambium Simple Definition

cortex

the tissue layer under the epidermis, it transports water and minerals
cortex Simple Definition

dermal tissue

the outer covering of a plant or animal
dermal tissue Simple Definition

endodermis

the inner layer of the cortex, it encloses the vascular tissue
endodermis Simple Definition

germination

the growth of a new plant from a seed
germination Simple Definition

ground tissue

the tissue that makes up the majority of a plant, it consists of the parenchyma, collenchyma and sclerenchyma
ground tissue Simple Definition

guard cell

one of a pair of cells that open and close plant stoma, to control gas exchange
guard cell Simple Definition

heartwood

the older wood at the center of a tree trunk, it no longer conducts water
heartwood Simple Definition

leaf blade

the thin, flat part of a leaf
leaf blade Simple Definition

meristem

a region of unspecialized cells, which divide to form different types of cells as a plant grows
meristem Simple Definition

nastic movement

plant movement independent of the direction of the stimulus
nastic movement Simple Definition

palisade mesophyll

the layer of cells just under the leaf epidermis where most photosynthesis takes place
palisade mesophyll Simple Definition

parenchyma cell

spherical, thin-walled cell with a large central vacuole, the most common plant cell
parenchyma cell Simple Definition

petiole

the stalk connecting a leaf blade to the plant stem
petiole Simple Definition

phloem

the vascular tissue that transports food in plants
phloem Simple Definition

pith

the storage tissue at the center of vascular plant stems
pith Simple Definition

plant epidermis

the outermost protective layer of a plant
plant epidermis Simple Definition

primary growth

growth that occurs at the tips of the stems and roots of a plant
primary growth Simple Definition

root cap

the tough cell layer that protects root tips as they grow
root cap Simple Definition

root hair

a hairlike growth that increases a root’s surface area for water and mineral absorption
root hair Simple Definition

sapwood

the secondary xylem layer around the herartwood, it transports fluids
sapwood Simple Definition

sclerenchyma

plant cells with thick, rigid cell walls that provide support
sclerenchyma Simple Definition

secondary growth

plant growth that thickens stems and roots
secondary growth Simple Definition

sieve tube element

a phloem cell arranged end to end to form a sieve tube
sieve tube element Simple Definition

spongy mesophyll

the layer of loose tissue and air spaces under a leaf’s palisade mesophyll layer
spongy mesophyll Simple Definition

stomata

the small openings on a plant leaf that allows oxygen and carbon dioxide in and out
stomata Simple Definition

tracheid

a hollow xylem cell with thick walls that transports water
tracheid Simple Definition

transpiration

the loss of water vapor through the stomata in a plant’s leaves
transpiration Simple Definition

vascular cambium

lateral meristem tissue that produces xylem and phloem cells, used to thicken roots and stems
vascular cambium Simple Definition

vascular cylinder

the center of a root or stem that contains the phloem and xylem
vascular cylinder Simple Definition

vessel element

a hollow, tubular cell that forms xylem vessels, which carry water and minerals
vessel element Simple Definition

xylem

plant tissue that moves water and nutrients up from the roots
xylem Simple Definition

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