EVOLUTION OF LAND PLANTS

From Last Day:

Closest Living Relatives of Land Plants - Charophytes

Chara Coelochaete

Some Charophytes

Typical Charophyte habitat

?

Adaptations? - sporopollenin (polymer)

Pollen grains – land plants

Closest Living Relatives of Land Plants - Charophytes

Why?? – 4 features

1) Rosette-shaped cellulose-synthesizing complex

2) Peroxisome enzymes

3) Structure of sperm

4) Formation of a phragmoplast

phragmoplast

These are all shared ancestral traits

What makes land plants unique

1. Alternation of generations

Two different kinds of organisms

1) Gameophyte 2) Sporophyte

What makes land plants unique

2) Walled spores produced in sporangia

Sporopollenin in walls -

What makes land plants unique

3) Multicellular gametangia

What makes land plants unique

4) Apical meristems

Who are the land plants and how are they related

Bryophytes Seedless Vascular Gymnosperms Angiosperms

Non-vascular Plants – The Bryophytes Liverworts Hornworts Mosses Club mosses Ferns

Gymnosperms Angiosperms Note: The bryophytes and the Bryophyta are not the same

Bryophyte – a collective term for the liverworts, hornworts and mosses (3 separate phyla)

Bryophyta – the formal Latin name for the phylum of the mosses

Non-vascular Plants – The Bryophytes Liverworts Hornworts Mosses Club mosses Ferns

Gymnosperms Angiosperms

Who are they?

1) Liverworts

Thalloid Leafy

Non-vascular Plants – The Bryophytes Liverworts Hornworts Mosses Club mosses Ferns

Gymnosperms Angiosperms

Who are they?

2) Hornworts

Non-vascular Plants – The Bryophytes Liverworts Hornworts Mosses Club mosses Ferns

Gymnosperms Angiosperms

Who are they?

3) Mosses

Non-vascular Plants – The Bryophytes Liverworts Hornworts Mosses Club mosses Ferns

Gymnosperms Angiosperms

Key feature of all the bryophytes

Gametophyte is dominant part of the life cycle

Sporophyte

Gametophyte

Life cycle of a Moss