Plant Structure and Growth


collenchyma cell

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


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


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


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


the space between nodes


the primary photosynthetic organ of vascular plants


tissue that undergoes repeated, continuous cell division


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


the stalk that attaches a leaf to a branch


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


the spongy central tissue of a stem

primary growth

vertical growth of stem and roots


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


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


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


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


the transport of materials through the phloem of vascular plants


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)


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

vascular plant

a plant that has tissues for transporting water or sap


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