3. leaves

Question 1

Parts of a leaf; complete vs incomplete (sessile)

Answer 1

Complete- blade, petiole, and stipules
Incomplete- missing one or more parts

Question 2

Main purpose of leaf?

Answer 2

Photosynethis, gas exchange, and transpiration

Question 3

Compound leaves – pinnately vs palmately

Answer 3

Pinnately- the leaflets are arranged along a central axis, called the rachis, similar to the way feathers are arranged along the shaft of a feather. Ex, rose
Palmately- all leaflets radiate from a single point at the end of the petiole, resembling the fingers extending from the palm of a hand. Ex, maple

Question 4

Leaf venation – pinnately vs palmately vs parallel

Answer 4

Pinnately- a central main vein (called the midrib) from which smaller secondary veins branch out on either side, resembling a feather
Palmately- several main veins spread out from a single point at the base of the leaf, resembling the fingers extending from the palm of a hand.
Parallel- veins that run parallel to each other along the length of the leaf. This type is common in monocot plants.

Question 5

Phyllotaxy – alternate, opposite, whorled

Answer 5

Phyllotaxy is the arrangement of leaves on a plant stem
Alternate- One leaf per node, leaves alternate sides.
Opposite- Two leaves per node, directly opposite each other.
Whorled- Three or more leaves per node, arranged in a circular pattern.

Question 6

Stomata – label, function

Answer 6

Guard cells: control the opening and closing of the stomatal pore
Stomatal pore: actual opening through which gases and water vapor pass in and out of the leaf
Gas exchange, transpiration, and water regulation

Question 7

Differences in xerophyte/hydrophyte leaves

Answer 7

Xerophyte- thick, waxy, reduced leaves with sunken stomata and adaptations for water storage
Hydrophyte- thin, flexible leaves with air spaces, a reduced cuticle, and stomata mainly on the upper surface

Question 8

leaf blade shapes: Spatulate; Rennate; Chordate

Answer 8

Spatulate- a shape resembling a spatula or spoon, with a broad, rounded tip and a gradually narrowing base
Rennate- Kidney-shaped with a rounded outline and slight basal indentation.
Cordate- Heart-shaped, with a pointed tip and indented base.