Plant Cells and Tissues; Plant Growth: Roots

Flashcards about plant cells, tissues, and growth of roots.

Root

A plant organ that functions in anchorage, support, storage, symbiosis with soil microbes, and absorption of water and minerals.

Taproot

The main vertical root in eudicots that gives rise to secondary branches called lateral roots.

Fibrous roots

A shallow network of roots in monocots where the primary root dies and new roots come off the stem.

Root cap

A terminal structure that protects the root apical meristem, secretes mucilage, and is the site of gravity perception.

Zone of cell division

Includes the RAM and immediate products

Zone of differentiation

Area where cells take on distinct types; root hairs emerge.

Zone of cell elongation -

Cells grow up to 10x initial length

Pericycle

The outer vascular layer surrounding the xylem and phloem where lateral roots arise.

Epidermis

The outermost tissue of a plant organ, protecting the plant from environmental insults and preventing desiccation.

Cortex

Starch-storing parenchyma with intercellular spaces.

Endodermis

One cell thick layer that creates a boundary with the vasculature.

Internodes

The span of stem between nodes

Nodes

Sites where structures extend from stem

Dermal Tissue

Plant tissue that covers and protects the plant

Vascular Tissue

Plant tissue that transports water, minerals, and sugars throughout the plant

Ground Tissue

Plant tissue that can serve as the site of photosynthesis, provide the supporting matrix for the vascular tissue, and help store water and sugars.

Parenchyma

Cells that are alive at maturity, have simple cell walls, can perform diverse functions and may divide and differentiate into other cell types.

Collenchyma

Cells that are alive at maturity with thick cell walls and function to provide structural support.

Sclerenchyma

Cells that have lignin embedded in very thick cell walls, function in support and protection, and may be alive or dead.

Sclereids

Small sclerenchyma cells with thick walls often found in fruit walls or seed coats.

Fibers

Elongated sclerenchyma cells found in bunches that function in structural support.

Trichomes

Hairlike outgrowths on stems, leaves, or flowers that can be glandular or non-glandular and function in defense, thermoregulation, and reflection.

Root hairs

Increase surface area for absorption of water and minerals

Xylem

The vascular plant tissue that conducts water and minerals upward from the roots to the rest of the plant.

Tracheids

Relatively narrow, dead when functional cells with totally open interiors and lignified cell walls where water moves laterally by pits.

Vessel elements

Open, dead cells with lignified cell walls, but much wider than tracheids, with open ends allowing the formation of long vessels.

Phloem

The vascular plant tissue consisting of living cells that transport sugars and other organic nutrients to the rest of the plant.

Sieve-tube elements

Connect end to end allowing formation of long sieve tubes; ends are not totally open but have sieve plates.

Phloem

The vascular plant tissue consisting of living cells that transport sugars and other organic nutrients to the rest of the plant.

Companion cells

Paired non-conducting cells connected to sieve-tube elements through plasmodesmata, passing sugars, nutrients, and large molecules to keep sieve-tube elements alive.

Pavement

Tightly knit, irregularly shaped epidermal cells.

petiole

The part of a leaf that connects the leaf blade to the stem, providing support and allowing for the transport of nutrients and water.