1. “Plant-Like” Protists:
Multicellular Algae

2. Multicellular Algae - Red, Brown, and Green Algae
AKA “Seaweed”
Algae lack an internal system of tubes to move water and material from one part of the plant to another
Most are multicellular
Can reach 60 meters in length, cells contain cell walls, contain chlorophyll a
Three groups of multicellular algae
Red
Brown
Green

3. Phylum Rhodophyta – Red Algae
Contain chlorophyll a and reddish accessory pigments called phycobilins – good for absorbing blue light and can live deeper than other algae
Store food as special starches
Found from far North to the tropics to a depth of 170 meters
Chondrus crispus, Irish moss – common red algae

4. Red Algae Examples
Chondrus crispus
Antithamnion plumula

5. Phylum Phaeophyta – Brown Algae
Chlorophyll a and c as well as brown pigment called fucoxanthin
Store food as special starches and oils
Important marine algae found in shallow temperate regions
Largest, and most complex of the algae
Kelp, sargassum, fucus

6. Fucus Anatomy

7. Brown Algae Examples
Fucus
Kelp

8. Phylum Chlorophyta – Green Algae
Chlorophyll a and b
Store food as starch, found in moist areas and fresh water
Some marine
Some live as single cells, some form colonies, and some are multicellular
Sexual and asexual reproduction
May be ancestor to land plants
Vulvox, spirogyra, ulva

9. Green Algae Examples
Vulvox
Ulva
Spirogyra

10. Reproduction in Algae
Alternation of generations – alternate generations are sexual and asexual – sexual reproduction involves the production of gametes and asexual production involves haploid cells called zoospores (switch back and forth)

11. Reproduction in Ulva – a Green Algae
Diploid algae called the sporophyte, haploid algae called gametophyte
Two different gametophytes – male and female – having two types of gametophytes is called heterogamy

12. Ulva Life Cycle MITOSIS MEIOSIS Zygote Gametes fuse Sporophyte Spores
FERTILIZATION
Gametes
Female gametophyte
MITOSIS
Diploid
Haploid
Male gametophyte

13. Reproduction in Fucus – a Brown Algae
Alternation of generations and heterogamy
Female gamete – egg
Male gamete - sperm

14. Human Uses of Algae Drugs Sushi Ice cream Salad dressing Pudding
Candy bars
Eggnog
Toothpaste
Deoderant
Agar……..