Search results
Results from the WOW.Com Content Network
Plants, along with other primary producers, produce the energy that other living beings consume, and the oxygen that they breathe. [3] It is thought that the first organisms on Earth were primary producers located on the ocean floor. [3] Autotrophs are fundamental to the food chains of all ecosystems in the world. They take energy from the ...
All animals are chemoheterotrophs (meaning they oxidize chemical compounds as a source of energy and carbon), as are fungi, protozoa, and some bacteria. The important differentiation amongst this group is that chemoorganotrophs oxidize only organic compounds while chemolithotrophs instead use oxidation of inorganic compounds as a source of energy.
Eukaryotic photoautotrophs include red algae, haptophytes, stramenopiles, cryptophytes, chlorophytes, and land plants. [6] These organisms perform photosynthesis through organelles called chloroplasts and are believed to have originated about 2 billion years ago. [ 1 ]
Autotrophs are vital to all ecosystems because all organisms need organic molecules, and only autotrophs can produce them from inorganic compounds. [1] Autotrophs are classified as either photoautotrophs (which get energy from the sun, like plants) or chemoautotrophs (which get energy from chemical bonds, like certain bacteria).
All of these habitats are able to sequester large quantities of carbon and support a biodiverse range of larger and smaller animal life. [76] Marine plants can be found in intertidal zones and shallow waters, such as seagrasses like eelgrass and turtle grass, Thalassia. These plants have adapted to the high salinity of the ocean environment.
Gross primary production (GPP) is the amount of chemical energy, typically expressed as carbon biomass, that primary producers create in a given length of time.Some fraction of this fixed energy is used by primary producers for cellular respiration and maintenance of existing tissues (i.e., "growth respiration" and "maintenance respiration").
Heterotrophic organisms have to take in all the organic substances they need to survive. All animals , certain types of fungi , and non-photosynthesizing plants are heterotrophic . In contrast, green plants , red algae , brown algae , and cyanobacteria are all autotrophs , which use photosynthesis to produce their own food from sunlight.
Many protist species can switch between asexual reproduction and sexual reproduction involving meiosis and fertilization. [6] In contrast to the cells of prokaryotes, the cells of eukaryotes are highly organised. Plants, animals and fungi are usually multi-celled and are typically macroscopic. Most protists are single-celled and microscopic.