Medicinal Plants: Hairs (Trichomes)

Vocabulary practice flashcards covering plant trichomes (hairs), their anatomical structure, classification, morphological varieties, and botanical occurrences.

Trichomes (Hairs)

Protrusions or extensions of epidermal cells that vary in size, shape, and characteristics, serving functions such as protection, reduction of transpiration in desert plants, and secretion of resin and oleoresin.

Papillae

Very short, conical protrusions of the epidermal cells.

Cicatrix

The scar left behind in the epidermis after a hair falls off.

Foot

The basal part of a trichome that is embedded within the epidermis.

Body

The free part of a trichome extending outward from the epidermis.

Non-glandular Hairs

Trichomes lacking a secretory gland head, classified according to cell number (unicellular or multicellular), branching type (branched or unbranched), and row count (uniseriate, biseriate, or multiseriate).

Glandular Hairs

Specialized trichomes structurally divided into a stalk and a head that function to secrete resin and oleoresin.

Warty Hair

A non-glandular, unicellular, unbranched hair with a roughened cuticular surface; characteristic of Senna.

Cystolith Hair

A non-glandular, unicellular, unbranched hair featuring an enlarged base containing calcium carbonate ($CaCO_3$); characteristic of Cannabis.

Digitate Hair

A non-glandular, unicellular, branched hair shaped like fingers; characteristic of Lavender.

Streaked Cuticle Uniseriate Hair

A non-glandular, multicellular, unbranched hair arranged in a single row of cells with visible cuticular streaks; characteristic of Stramonium.

Twin Hair

A non-glandular, bicellular biseriate hair consisting of two adjacent cells joined longitudinally; characteristic of Arnica.

Multicellular Biseriate Hair

A non-glandular, multicellular, unbranched hair consisting of two vertical tiers or rows of cells; characteristic of Calendula.

Shaggy Hair

A non-glandular, multicellular, unbranched, multiseriate (pluriseriate) hair consisting of multiple columns of cells; characteristic of Cumin.

Peltate Hair

A non-glandular, multicellular, branched hair with a very short axis surmounted by a shield- or plate-like structure of closely joined cells; characteristic of Olea.

Candelabra Hair

A non-glandular, multicellular, branched hair with a central uniseriate axis bearing multiple whorls of unicellular branches; characteristic of Verbascum.

Stellate Hair

A non-glandular, multicellular, branched hair with unicellular hairs radiating outward from a common center like a star; characteristic of Tilia.

Capitate Hair

A glandular hair with a unicellular, unbranched stalk and a multicellular head; characteristic of Mentha.

Clavate Hair

A club-shaped glandular hair featuring a unicellular, unbranched stalk and a multicellular head; characteristic of Stramonium.

Labiaceous Hair

A glandular hair with a unicellular, unbranched stalk and a multicellular head composed of $8\text{ to }16$ radiating secretory cells; characteristic of Mentha.

Uniseriate Stalk Glandular Hair

A glandular hair possessing a multicellular, uniseriate, unbranched stalk and a secretory head; characteristic of Belladonna.

Compositae Hair

A glandular hair with a multicellular, biseriate, unbranched stalk and a biseriate head; characteristic of Chamomile.

Shaggy Glandular Hair

A glandular hair with a multicellular, multiseriate (pluriseriate), unbranched stalk and a multicellular secretory head; characteristic of Cannabis.

Branched Glandular Hair

A glandular hair with a multicellular, branched stalk bearing glandular heads; characteristic of Hyoscyamus.

Surface Preparation Scheme

The six-parameter diagnostic scheme for describing leaf epidermises: Shape of Cells, Anticlinal walls, Cuticle, Stomata, Hairs, and Content.