Plant Structure and Growth

Vocabulary

collenchyma cell

elongated cell that supports new growth, particularly in areas of a plant that need extra strength

cuticle

a clear, waterproof layer on leaves and stems that is secreted from epidermal plant cells and prevents water loss

diffusion

random movement of molecules along a concentration gradient from an area of higher concentration to an area of lower concentration

epidermis

the outer coating of the leaf and stem which has a protective cuticle or waxy layer; typically, a single cell layer

guard cell

one of two curved cells surrounding stoma that work jointly to open and close the stoma

internode

the space between nodes

leaf

the primary photosynthetic organ of vascular plants

meristem

tissue that undergoes repeated, continuous cell division

node

the point at which aerial roots, leaves, and buds, which may form additional branches, are attached to a main stem

parenchyma cell

thin-walled, large cell with a very large central vacuole, and numerous plastids, which performs metabolic processes, including photosynthesis

petiole

the stalk that attaches a leaf to a branch

phloem

the series of tissues that transport sugars and other materials from the leaves of plants to their roots

pith

the spongy central tissue of a stem

primary growth

vertical growth of stem and roots

root

organ of a vascular plant that provides water and mineral support and anchors a plant to the soil

root system

the complete mass of roots belonging to a plant

sclerenchyma cell

a hard, woody cell that, along with other cells, provides structural support

secondary growth

plant growth by width, such as with trees

shoot system

the stem, branches, and leaves of a plant

solute

any substance dissolved in water; the nutrition plants need to thrive

stem

a vascular support system made up of nodes and internodes that support branches and reproductive structures

stipule

small flap that protects new leaf growth

stoma (plural, stomata)

small opening mostly found on the undersides of leaves that allows for gas exchange between the plant and the external environment

translocation

the transport of materials through the phloem of vascular plants

transpiration

the loss of water from the plant leaves through the stomata as a result of temperature and humidity (faster at higher temperatures and slower in humid conditions)

trichome

hair-like outgrowth on a plant shoot that functions to deter herbivores

vascular plant

a plant that has tissues for transporting water or sap

xylem

a vein-like tissue that carries water from roots and stems to leaves