1. Algae

2. • Nearly 75% of the world’s oxygen
produced by algae
• One of the major food source of marine ecosystems
• Eukaryotic, photosynthetic (autotrophs)

3. STRUCTURE Four types of algae Unicellular Colonial Filamentous
multicellular

4. THE TYPE OF ALGAE
Unicellular
Colonial
multicellular
Filamentous

5. CLASSIFICATION OF ALGAE
SEVEN PHYLUM BASED ON
COLOR
TYPE OF CHLOROPHYLL
FOOD-STORAGE SUBSTANCE
CELL WALL COMPOSITION

6. Algal groups
In today’s lab, we will look at algal groups:

7. Chlorophyta: Green Algae
• Mostly found in fresh water
• Contain chlorophylls a and b
• Store energy as starch (carbohydrate)
• Cell walls made of cellulose

8. Genus: Chlamydomonas
Motile, unicellular algae

10. Genus: Spirogyra
Filamentous

12. Genus: Volvox Consists of many Chlamydomonas-like
cells bound in a colony
Each cell has two flagella

14. Phaeophyta: Brown Algae
• marine algae
• No unicellular or colonial forms
• Contain chlorophyll c and brown pigment
fucoxanthin
• Range in size from microscopic to
over 50 meters long

15. Genus: Fucus • Also called “rockweed” • Typically attaches to rocks
• Outer surface covered by gelatinous sheath

16. • Tips of branches (called conceptacles)
may be swollen and contain reproductive
structures – oogonia (female, produce
eggs) and antheridia (male, produce
sperm)

18. Rhodophyta: Red Algae • “Red algae”
• Contain chlorophyll d and red pigments
(phycobilins)
• Mainly multicellular
• Typically in warm marine water
• Can be attached, free-floating, filamentous,
or parenchymatous (fleshy)

19. Chrysophyta “Diatoms” • Unicellular
• Contain chlorophylls a and c, as well as
xanthophyll pigments (golden-brown)
• Have hard cell wall made of silicon dioxide

20. Diatoms can be:
• Pennate (bilateral
symmetry) Or
• Centrate (round,
radial symmetry)

22. Euglenophyta • Unicellular • Motile (two flagella)
• Contain chlorophylls a and b
• Mainly freshwater algae
• Main cell wall component: protein (flexible)
• Asexual reproduction

23. Genus Euglena
Unicellular