Algae

• Algae are both unicellular and multicellular, they are photosynthetic, each has chlorophyll and other photosynthetic pigments
• Euglenoids: only unicellular, found in aquatic environment, use flagella to move, no cell wall, can eat food in surrounding when there is no light, decomposers
• Diatoms: shells made of silica, unicellular, pigment called carotenoids, are autotrophic, primary food source for organisms, produce a lot of Earth's oxygen
• Dinoflagellates: spin in circles using two flagella, create toxins that can kill, some are known to glow
• Red, Green and Brown Algae: seaweeds, multicellular aquatic organisms, have different colours, produce oxygen, brown ones have air bladders to float to surface