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
Photosynthesis | Encyclopedia. com Photosynthesis Photosynthesis is the biological conversion of light energy into chemical energy This occurs in green plants, algae, and photosynthetic bacteria
Rhodophyta - Encyclopedia. com Rhodophyta (red algae) A group of Eukarya which are mostly red in colour; no flagellated cells are formed, and the storage product is a type of starch known as floridean starch Sexual reproduction tends to be complicated Red algae may be unicellular, but most are filamentous or membranaceous The majority occur in the sea, but some are freshwater or terrestrial The group includes 1 class
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)
Pyrrophyta - Encyclopedia. com Cryptomonads for instance, are considered red-brownish algae of Cryptomonadida Order by botanists, and protozoans of Cryptophycea Class by zoologists This controversy is due to the unusual characteristics of these two phyla, sharing features with both plants and animals
Protozoa - Encyclopedia. com Further complicating a precise definition of protozoa is the close relationship between some protozoa and unicellular algae Modern taxonomic treatments recognize these similarities and group protozoa, photosynthetic unicellular algae, and slime molds together as protists or protoctists