33/ 34: Leave/ Plant Structure

Question 0

4 basic leaf structures, placement

Answer 0

1. broad flat Blade (top)
2. stalk-like Petiole (below blade)
3. some have Stipules (small leaf-like outgrowths from the base)
4. Leaf placement generally Below an Axillary Bud

Question 1

____ are cells surrounding tiny pores in the epidermis that faciliate the diffusion of CO2 into leaves or Herbaceous stems

Answer 1

Guard Cells

Question 2

Describe Simple and Compound(2 types) leaf forms

Answer 2

• simple: having a single blade
• Compound: hving a blade divided into 2 or more leaflets(which don’t have axillary buds)
• pinnately and palmately compound

Question 3

3 types of leaf arrangement on a leaf(describe)

Answer 3

• alternate (one leaf at each node)
• opposite (2 at each node)
• whorled (3 or more at each node)

Question 4

2 characteristics of the Epidermis on leaf (does it have chloroplasts), what are 2 specialized cells on it, what does the Waxy Cuticle do ?

Answer 4

• Covers upper and lower surfaces on leave blade
• mostly transparent (no chloroplasts) protective cells
• specialized cells: guard cells, Trichomes (hairs)

waxy cuticle: coats epidermis and inhibits water evaporation

Question 5

Small pores in epidermis are called____which permit____ ____ and are surrounded by ____ which are often associated with special epidermal cells ( ____ cells)

Answer 5

Stomata
Guard Cells
Subsidiary cells

Question 6

how is the stoma formed/controlled, and what do subsidiary cells provide

Answer 6

• osmotic movement of water causes guard cells to become turgid(pressurized), forming a pore
• provide a reservoir of water and ions

Question 7

2 layers of Mesophyll (middle leaf), their arrangement and function

Answer 7

• Palisade Mesophyll: (top) Densely packed, photosynthesis

- Spongey Mesophyll: (bottom) with Air spaces, gas exchange