plant biology lecture 11- leaves again

what are pinnate compound leaves

 leaflets are born on the rigus (basically extension of the petiole)

what are palmate compound leaves

multiple leaves emanate from a single point at the end of the petiole

what are stipules

Scale of leaf-like appendages that arise at nodes from the base of leaves

what is mesophyll

Parenchyma cells specialised for photosynthesis

what is a mesophyte leaf

(plants that don’t require lots of water, but also don't like really dry conditions

what is a hydrophyte leaf

plant that lives on surface of water

what is a xerophyte leaf

Plant that lives in dry and environments

characteristics of hydrophyte leaf

Spongy parenchyma has big intercellular spaces (aerenchyma) to help plant float on water surface

characteristics of xerophyte leaf

• multiple epidermis layers to keep moisture inside

• waxy cuticle

• guard cells are placed into chambers lined with trichomes — boundary layer between inner surface and dry outside air

what are the different kinds of epidermal tissue

Pavement cells: jigsaw puzzle cells

Guard cells: (open and close stomata)

Trichomes:

Root hairs: Cell outgrowths to increase surface area for water + mineral uptake

what are larger veins in a leaf typically surrounded by

parenchyma cells

what is a bundle sheath

 collection of cells that have casparian strips

• surrounds smaller veins (vascular bundles)

• isolates vascular tissue so plant can regulate what goes in/out of cell

• stops transport across apoplast. forces material into symplast

what is C3 grass

• C3 photosynthesis

• smaller bundle sheaths

• smaller chloroplasts

• wider space between vascular bundles

• lots of intercellular space

example: rye grass

what is C4 grass

• C4 photosynthesis

• larger bundle sheaths

• larger chloroplasts

• closer space between vascular bundles

• less intercellular space

what % of dicots undergo C4 photosynthesis

~5%

what % of monocots undergo C4 photosynthesis

~40%