Quick algae review
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Habitat
Structure
Type of cell
Transport
Reproduction
MOSSES and FERNS
Seedless Plants - Chapter 21
According to The Theory of Evolution:
Life (algae) began in the sea, and for millions
of years living things remained in the sea.
Yet, slowly, life emerged onto land.
The first land plants have to meet the
challenges of living on dry land. Let’s take a
look at how they did it.
Progression
450-500mya
Algae
(aquatic plants)
These organisms
have to face up
to the challenges
of living on dry land.
Algae-like
Land plants
Bryophyte
-mosses
-liverworts
-hornworts
Tracheophyte
-ferns
-higher plants
What are some challenges to
life on land?
• Drying out
• Food
• Diffusion of O2 and CO2
• Successful reproduction
Adapting to Life on Land
1. have a constant supply of water to cells
2. be exposed to
make food and thus need
rigid support to hold up their leaves.
3. be able to transport nutrients & water
throughout the plant
water
- vascular tissue + rhizoids
food
4. Must be able to exchange O2 & CO2 w/o losing
too much H2O
5. Be able to reproduce without water
- small spores, flagellated sperms
Mature moss capsule
Moss capsules
Phylum Bryophyta:
Moss, Liverworts, Hornworts
Leptostomum inclinans
Papillaria crocea
Polytrichum juniperinum
Bryum argenteum
Chinese Club Moss
• Stop here
• Homework read p. 449-451
• Questions 1-3
How Do Bryophytes Get Water?
Problem: Non-vascular plant
1. Via osmosis and capillary action
2. Leaves have only one or two cells
3. Only about 2 to 5 cm tall, cling to damp
soil, sheltered rocks, and the shady
side of trees
4. Rhizoids: root-like structures; mostly
for anchor
Critical Thinking
• Your friend finds a small plant growing in the
desert. He identifies the plant as a moss.
Explain why this plant is probably not a moss.
• Don’t think out loud please.
Structure of Moss
• Please find an empty spot on your handout. =)
Life Cycle of Mosses
• Alternation of generations:
process of switching from
asexual (haploid) to sexual
reproduction (diploid)
Alternation of Generation
in Mosses
• Germinate – develop into a plant
• Protonema – transitory stage of moss plant
• Archegonium
– female organ
– egg develops here
- Protects gametes
• Antheridium
- male organ
- sperm develops here
• Protects gametes
Refer to handout
on moss reproduction
Your task for the rest of the class.
• Create a placemat and make sure you cover
these topics:
– Phylum
– Adaptation to life on land (5 points)
– Where they are found
– Type of reproduction
– Appearance (description + diagram)
– Diagram
– Physical features (6 points)
Out of 22marks