PlantGeneaology04

advertisement

Plant Genealogy and

Taxonomy Notes

Know underlined terms

I. NON-VASCULAR PLANTS:

• Algae, mosses

• First to evolve on earth (about

470 million years ago). No special vessel-like system for transmission of fluids.

II. VASCULAR PLANTS

:

A plant’s “circulatory system”

• Special vessel-like system for transmission of fluids:

A. Non-Seed Bearing (spores):

• EX: Ferns

Evolved about

400 mya.

II. VASCULAR PLANTS

:

B. Seed-bearing:

• 1. Gymnosperms “naked-seed”

(no fruit). Evolved ˜ 360 mya:

• male/ female parts; disperse, collect pollen; form seeds

• EX: Conifers (pines, redwoods, etc.)

II. VASCULAR PLANTS

:

B. Seed-bearing:

• 2. Angiosperms “covered seeds”; flowering plants (fruit). Evolved ˜180 mya.

• male/ female parts in flower; disperse, collect pollen; form fruits and seeds

II. VASCULAR PLANTS

:

• 2. Angiosperms:

Where seed stores food

--like an egg’s yolk.

• a. Monocots (1 cotyledon [1 seed lobe], parallel leaf veins):

• EX: Grasses, corn

II. VASCULAR PLANTS

:

• 2. Angiosperms:

• b. Dicots (2 cotyledons [2 seed lobes], networked leaf veins):

• EX: most other spp.

II. VASCULAR PLANTS

:

• 3. Other descriptions of vascular plants (may be gymnosperms or angiosperms, monocots or dicots):

• Annuals: Plants that complete their lifecycle in a year or less

(go to seed every year)

• Perennials: Plant that lives for more than 2 years.

QuickTime™ and a

TIFF (Uncompressed) decompressor are needed to see this picture.

QuickTime™ and a

TIFF (Uncompressed) decompressor are needed to see this picture.

III. PLANT EVOLUTION

• Consider the power and role of evolution in plant genealogy:

• A. Background: What is evolution?

Cumulative changes in a population as a result of:

1. appearance of variation caused by mutation), in a population (often

2. a selective force that selects for or against the survival of certain individuals in the population

3.

reproduction : passing on of the selected characteristic that allowed for survival.

III. PLANT EVOLUTION

• B. Where did flowers come from

(what is the source of variation in the plant population)?

Modified/ adapted leaf structures.

• C. Why were flowers selected?

Sexual reproduction increases variation--vital to evolutionary process. Flowers are a means of sexual reproduction.

Download