Plant Structure

Question 1

Roots functions

Answer 1

Anchor
Absorb and transport nutrients ( water by osmosis, nutrients by diffusion/active transport)
Storage

Question 2

Types of roots

Answer 2

Tap roots- one main root growing from radicle eg dandelion
Fibrous roots- many equal sized roots arising from stem base eg grass
Adventitious roots- don’t grow from radicle eg onion base

Question 3

Root structure

Answer 3

Differentiation zone -cells develop into 3 types (dermal, ground, vascular) 
Elongation zone- cells grow in length
Meristematic zone(cell production) - growth of new cells by mitosis 
Protection zone- root cap protects the cell as the root pushes through the soil

Question 4

State location and functions of parts of root

Answer 4

Dermal: outer covering, protection
Ground: between dermal and vascular, photosynthesis/ store food
Xylem: vascular bundle, transport water +minerals
Phloem: vascular bundle, transport food

Question 5

Functions of leaf

Answer 5

Photosynthesis
Transpiration
Gas exchange

Question 6

Structure of leaf

Answer 6

Flattened leaf blade = lamina (photosynthesis)
Petiole = leaf stalk
No petiole= sessile

Question 7

Location of vascular tissue in leaf

Answer 7

Midrib and veins

Question 8

Venation of leaves

Answer 8

Parallel: veins run alongside each other

Net/ reticulate: branching of veins

Question 9

Classification of plants

Answer 9

Cotyledon- embryonic seed leaf ( first leaf that develops)
Monocot- one embryonic seed leaf eg bluebell, grass
Dicot- two embryonic seed leaves eg sunflower, buttercup

Question 10

Stem functions

Answer 10

Support the aerial parts of the plant
Transport water and minerals from roots to leaves
Transport food from leaves to roots
Photosynthesis (green stems)

Question 11

Node

Answer 11

Point at which leaf is attached

Question 12

Internode

Answer 12

Distance between two nodes

Question 13

Stem structure

Answer 13

Apical bud: meristem, location of cell division (growth upward)
Leaf scar: where leaf has fallen
Scale scar: where apical bud was last year
Lateral bud: growth side branches
Lenticels: openings on stem, site of gas exchange

Question 14

Xylem tracheids structure

Answer 14

Hollow 
Long and tapered 
Dead cells overlapping 
Pits: pores that allow water to pass through 
Lignin: strengthening material 
Found in: pine trees

Question 15

Xylem vessels structure

Answer 15

Dead cells joined end to end
Wider, continuous tube (not tapered )
Where found: flowering plants
More efficient than tracheids

Question 16

Phloem structure

Answer 16

Sieve tube cells: transport food
Companion cells: living cells, contain nucleus to control sieve tube activities
Sieve plates: contain pores for movement of substances
Cellulose instead of lignin in cell walls