Plant Science test 2-Plant leaves

Plant Leaves (pt 1 of review)

Function of Leaves

Photosynthesis and transpiration

Leaf tissues

Epidermal Ground and Vascular Tiisue

Monocot

Narrow blades with parallel veins

Dicot

“Broad leaf”, various shapes with netted veins

Blade (dicot)

Broad thin tissue (Lamina)

Petiole (dicot)

Small stem like structure that attaches the blade to the stem

Midrib (dicot)

Central structure that runs the length of the blade

Stipules (dicot)

Area at the base of petiole where leaf actually attaches

Sessile leaves (dicot)

Attach directly to a stem and lack a petiole and stipule

Sheath (sheath)

Area where the blade forms a covering around the stem

Ligule (monocot)

Row of fine hairs present at the junction of the blade and sheath

Auricles (monocot)

“Hinge” like structure that tilts the blade away from the plant

Leaf shapes- Simple

One undivided blade

Leaf shapes- Compound

Consist of several leaflets

Pinnate (Compound)

Leaflets are arranged in pairs along the leaf axis

Palmate (Compound)

All leaflets are attached to the petiole at one place

Pinnately compound

Leaflets are sub-divided

Other characteristics of shapes of leaves

Leaf margins, tips, base, shape, venation

Environmental Factors on leaves

Sun, shade, and water

Blade (monocot)

Narrower linear tissue with parallel veins

Cutin

waxy coating that covers the
outside surface of epidermal cells,
reduces water loss

Xerophytes

Plants that grow in arid regions

Translocation

Movement of glucose (sugars) through the plant

Hydrophytes

Plants that grow in aquatic conditions