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- Algae - Encyclopedia. com
Algae Algae (singular: alga) are photosynthetic, eukaryotic organisms that do not develop multicellular sex organs Algae can be unicellular, or they may be large, multicellular organisms Algae can occur in salt or fresh waters, or on the surfaces of moist soil or rocks The multicellular algae develop specialized tissues, but they lack the true stems, leaves, or roots of the more complex
- Green Algae | Encyclopedia. com
green algae Large group of marine and freshwater algae (phylum Chlorophyta) They are distinct from other algae by virtue of possessing cup-shaped chloroplasts that contain chlorophyll b, and by producing cells with flagella at some stage in their lives Green algae range in size from microscopic single-cell types to large, complex seaweeds
- Cyanobacteria - Encyclopedia. com
Cyanobacteria Cyanobacteria (blue-green algae [1]) are microorganisms that structurally resemble bacteria (they lack a nucleus and organelles ) However, unlike other bacteria, cyanobacteria contain chlorophyll a and conduct oxygenic photosynthesis
- Evolution of Plants - Encyclopedia. com
Evolution of Plants Plants, descended from aquatic green algal ancestors, first appeared on land more than 450 million years ago during or prior to the Ordovician period This event preceded the colonization of land by four-footed animals (tetrapods), which occurred considerably later in the Devonian period (408 to 360 million years ago) Understanding the origin of plants is important because
- Protista - Encyclopedia. com
Protista Background Classification Protozoa Algae Slime molds and water molds Disease-causing protists Beneficial protists Resources The kingdom Protista is the most diverse of all of the eukaryotic kingdoms It is certainly not monophyletic and its members really only share the fact that they have a simple structure, without any obvious tissues or organs There are more than 200,000 known
- Amoeba - Encyclopedia. com
The amoeba mainly eats bacteria, algae, and other protozoans Any waste that remains after the food is digested is released from a contractile vacuole (one that can open and close) Water also flows into the amoeba by the process of osmosis (in which water flows through a membrane until the solutions on either side of it are at equal strength)
- Protists - Encyclopedia. com
Some species of brown algae have an air bladder to keep the thallus floating at the surface of the water, where more light is available for photosynthesis Brown algae store their energy as laminarin, a carbohydrate The phylum Chlorophyta is known as the green algae This phylum is the most diverse of all the algae, with greater than 7,000
- Photosynthesis - Encyclopedia. com
Photosynthesis Photosynthesis is the biological conversion of light energy into chemical energy This occurs in green plants, algae, and photosynthetic bacteria
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