Biology

Lateral meristem

sides of stems and roots. Growth; increase diameter.

Apical meristem

tips of stems and roots. Growth; increase length at tips

Cortex

tissue of unspecialized cells lying between the epidermis (surface cells) and the vascular, or conducting, tissues of stems and roots. Cortical cells may contain stored carbohydrates or other substances such as resins, latex,

Gynonsperms

-non-flowering (no fruits either) seed plants -Evolved earlier than the flowering plants -First fully terrestrial plants to evolve ---> Usually have needles

Dermal Tissue

Flat, living epidermal cells in non woody parts; flat, dead cork cells in woody parts. Located outermost layers of cells. Absorption and protection in roots, in stems gas exchange, and protection. Lastly function in leaves gas exchange, protection.

Angiosperms

Flowering seed plants -Produce flowers & fruits - Most diverse and widespread of all plants -Have broad leaves -- collect more sunlight for photosynthesis - Drop their leaves to conserve water - Lots of animals think the leaves are tasty -Defenses: spines, poison, wax, fuzzy, thorns We use some of their defenses for medicines, stimulants, spicy flavors

Ground Tissue

Mostly epidermal cells, usually with some collenchyma and fewer sclernchyma. Located b/w dermal and vascular in nonwoody plant parts. In roots and stems they support and store. In leaves they do photosynthesis.

Palisade mesophyll

The palisade mesophyll consists of one or several layers of elongated, narrow parenchyma cells with their long axes at right angles to the axis of the leaf and are situated under the adaxial epidermis. Chloroplasts are especially concentrated in the palisade mesophyll and it is in these cells that much of the photosynthesis in a tree takes place.

Spongy mesophyll

The spongy mesophyll consists of irregularly shaped parenchyma cells which are located between the palisade mesophyll and the abaxial epidermis. Spongy mesophyll cells contain less chloroplast than the palisade mesophyll cells but photosynthesis take place in these cells as well.

Pericycle

a thin layer of plant tissue b/w the endodermis and the phloem

Guard Cells

are cells surrounding each stoma. They help to regulate the rate of transpiration by opening and closing the stomata.

stomata

are minute aperture structures on plants found typically on the outer leaf skin layer, also known as the epidermis. They consist of two specialized cells, called guard cells that surround a tiny pore called a stoma.

Vascular Tissue

elongated cells- dead xylem and living phloem, also parenchyma and fibers. Located in tubes throughout plant. Function in roots, stems, and leaves they transport and support.

Cuticle

is a water-impervious protective layer covering the epidermal cells of leaves and other parts and limiting water loss. It consists of cutin, a waxy, water-repellent substance allied to suberin, which is found in the cell walls of corky tissue.

Endodermis

is the central, innermost layer of cortex in some land plants. It is made of compact living cells surrounded by an outer ring of endodermal cells that are impregnated with hydrophobic substances (Casparian Strip) to restrict apoplastic flow of water to the inside.

Pith

soft or spongy tissue in plants or animals, in particular.

Epidermis

the outer layer of cells covering an organism

Root hair

they are the rhiziod of a vascular plants, is a tubular outgrowth of trichoblast, a hair forming cell on the epidermis of a plant root.