Structure of Higher Plants

4 root functions

1. Absorption

2. Transportation

3. Storage

4. Plant support

What 2 things do roots absorb

1. Water

2. Nutrients

What 4 things do roots transport

1. Water

2. Nutrients

3. Sugars

4. Plant growth regulators

How do the roots provided plant support?

Anchorage

Function of root hairs

Involved in absorption of nutrients from the soil

Function of root cap + meristem

Conducting tissue, involved in conducting moisture + nutrients to the plant

4 basic types of roots

1. Fibrous

2. Tap

3. Tuberous

4. Adventitious

Fibrous root definition

Main root is branched + most roots are of similar size

Benefit of fibrous roots

Effective for controlling soil erosion

2 examples of fibrous roots

1. Grasses

2. Strawberry

Tap root definition

One (or two) main central root

Tap root function

Stores food reserves

Tap root example

Carrot

Tuberous root definiton

Areas of root are swollen

Tuberous root function

Starch storage

Tuberous root example

Potato, sweet potato

Adventitious root definition

Form at any place on the plant other than the root formed during germination

Where do adventitious roots originate from?

Stem or leaf tissue

Which root type may originate naturally or can be stimulated to form artificially from cuttings?

Adventitious roots

2 examples of adventitious roots

1. Corn

2. Tomato

3 functions of stems

1. Attachment

2. Conduction

3. Storage

3 things that stems support

1. Leaves

2. Flowers

3. Fruits

What does stem conduction refer to?

Metabolites

4 types of metabolites (in conduction function of a stem)

1. Sugars

2. Water

3. Plant growth regulators

4. Proteins

2 things that stems store

1. Metabolites

2. Pigments

4 stem structures

1. Lenticel

2. Node

3. Internode

4. Bud

Lencticel purpose

Gas exchange (pore)

Identify the stem structure

Lenticel

Node

Leaf + bud attachment

Internode

Stem portion between nodes

Bud

Underdeveloped or compressed stems, leaves and/or flowers

Terminal bud

Bud at the end of a stem

Axillary bud

Bud at the base of a petiole or branch

Adventitious bud

Bud that arises from internodes or leaves

Crown

Compressed stem

Spur

Woody stem with restricted growth

Stolon

Horizontal stem that rings along the soil surfrace

Tendril

Twines around objects for support

Prickle

Sharp projections along the stem; primarily at internodes; can break off

Thorn

Sharp axillary branch, primarily at nodes, cannot break off

4 below ground stems

1. Bulb

2. Corm

3. Rhizome

4. Tuber

Bulb

Compressed, modified shoot; disk-shaped stem surrounded by fleshy leaves

2 types of bulbs

1. Tunicate

2. Non-tunicate

Tunicate bulb

Covered with dry scaly leaves that serve as protection

Non-tunicate bulb

No outer covering

Corm

Swollen stem base; solid stem structure with distinct nodes (horizontal lines) and internodes

Rhizome

Horizontal underground stem; primarily for storage

Tuber

Enlarged underground stem; primarily for storage

2 functions of leaves

1. Photosynthesis

2. Transpiration

2 purposes of transpirations

1. Promotes water uptake

2. Cooling the plant

2 functions of stomata

1. Gas exchange (CO2 to water vapor)

2. Cooling

Blade

Broad flat surface w/ receptor pigments

Petiole

Positions leaf and contains vascular system for transportation; connection to stem

Stipule

Small leaf structure at the base of the petiole

Spines

Sharp, pointed leaves; protect plants; modified stipules

Midrib

Central vein of the leaf; usually continuous with the petiole

Margin

The rim or final limit of the blade

Simple leaf shape

One leaf attached to a petiole

5 forms of simple leaves

1. Pinnate

2. Palmate

3. Needle

4. Awl

5. Scale

Pinnate

Veins extend from a single midrib

Palmate

Veins extend from multiple midrib

Needle

Narrow blades that are grouped in bundles

Compound leaf shape

Contains multiple leaf blades attached to a petiole

4 forms of compound leaves

1. Single

2. Palmate

3. Double

4. Trifoliate

Compound-single

Leaflets arranged along an axis

Compound-double

Leaflets arranged along 2 axes before attaching to the stem

Compound-trifoliate

3 leaflets originate from 1 central point on the petiole

Compound-palmate

Leaflets attached to a single petiole forming the outline of a palm

3 leaf arrangements

1. Alternate

2. Opposite

3. Whorled

Alternate leaf arrangement

One leaf per node

Opposite leaf arrangement

2 leaves per node

Whorled leaf arrangement

3 or more leaves per node

3 leaf attachments

1. Sessile

2. Petioled

3. Sheathing

Sessile

Leaf directly attached to stem

Petioled

Leaf attached to petiole

Sheathing

Leaf base enwraps stem