A lgae

introduction to alge.

1. Algae Chpter-7 Section-2

2. Objectives General information about algae. Explain the general characteristics of algae. Describe the various body structure of algae.

3. What is algae? Algae are plantlike organisms Belong to kingdom Protista They are doing photosynthesis The body portion of an algae is called thallus

4. Characteristics Algae are a diverse group of Protists . Range from microscopic single-cell organisms to a large seaweeds that may be hundreds of feet long. Unlike protozoa algae are autotrophic protists . They have chloroplasts and produce their own carbohydrates by photosynthesis Most of algae are aquatic and have flagella at some point of their life-cycle In addition algae cells often contain pyrenoids .

5. structure Based on the structure of algae 4 types are recognized. Unicellular algae Multicellular algae Colonial algae Filamentous algae

6. Unicellular algae Consist of one cell Most of them aquatic that compose the phytoplankton. Phytoplankton: a population of photosynthetic organisms.

7. phytoplankton phytoplankton produce almost half of the world carbohydrates Provide huge amount of nutrients for aquatic organism. Also produce oxsygen

8. Multicellular algae Often have a large and complex thallus For example Ulva

9. Colonial algae Have a structure that consist of groups of cells Acting in a coordinated manner. For example: Volvox

10. Filamentous algae Have a slender, rod-shaped thallus composed of rows of cells. for example: Spirogyra

11. Next lesson Reproduction Classification