Classification of Angiosperms

The Flowering Plants

Two Major Groups

Monocots Single cotyledon Parallel veins Flowers in multiples of 3’s

Dicots Two cotyledons Netted veins Flowers in multiples of 2, 4 or 5

Monocot and Dicot plant

FRUITS

SIMPLE Dry (poppy seed, milkweed, wheat) Fleshy (peach, plumb, apple, tomato, grape)

AGGREGRATE Flowers with several carpels Raspberry, strawberry

MULTIPLE Cluster of flowers Pineapple

Simple, aggregrate and multiple fruit

SEED STRUCTURES

Micropyle Opening through which the pollen tube grows to

deliver pollen to the ovary (ovules) Plumule

Epicotyl + embryonic leaves First leaves to emerge during germination

Hypocotyl Stem like area between radicle and cotyledon

SEED STRUCTURES (2) Radicle

Embryonic root First to emerge from the seed during germination

Cotyledon Fleshy part of the seed; food storage for plant

embryo until germination Hilum

Seed scar; where seed was attached to the ovary wall

Seed Coat Covers and protects the seed during dormancy

Typical Seed

Germination

Dormancy Allows seed to germinate when conditions are

favorable How do you know germination has occurred?

Radicle emerges Leaves

Photosynthesis begins Cotyledons no longer needed

Factors that Trigger Germination

Water Oxygen Temperature Light Fire Freezing temps. Animal digestive tract Hormones

Plant Hormones

Auxins Regulate plant growth

Hormones (2)

Cytokinins Promotes cell division (roots and stems)

Gibberellins Promote growth Stimulate germination

Abscisic Acid Inhibits growth of buds and germination

Ethylene Gas that stimulates ripening of fruits

Hormones (3)

Oligosaccharins Regulate growth and development Defense against disease

TROPISM

Plant movement towards or away from a stimuli

EXAMPLES Phototropism (light) Thigmotropism (touch) Gravitropism (gravity) Chemotropism (chemical/hormones) Hydrotropism (water)

THE FLOWER

The reproductive structure for the flowering plant

Perfect Flowers Both stamens and carpels present Self or cross pollination

Imperfect Flowers Either stamens or carpels present Cross pollination only

Female Reproductive Parts

Essential Carpel

Pistil (fused carpels) Stigma, style, ovary

Stigma Sticky to trap pollen

Style Tube from stigma to ovary

Ovary Holds the ovules

Female Flower Parts

C

A

R

P

E

L

Male Reproductive Parts

Essential Stamen

Male reproductive part Anther and filament

Anther Produces pollen

Filament Supports the anther

Male Flower Parts

Nonessential Flower Parts

Petal Attract pollinators Top whorl

Sepal Protect developing flower Bottom whorl

Corolla Both whorls

Nonessential Flower Parts

Flowers