Organisms that cannot photosynthesize and produce their own food are called HETEROTROPHS. Heterotrophs must obtain energy from organic matter that was produced by autotrophs. Both autotrophs and heterotrophs perform respiration to utilize the energy stored in organic compounds by photosynthesis. In respiration, sugars are broken down using O2, giving off CO2 and H2O as a result.
Molecules are organized into ORGANELLES (Organelle-basic biological significant unit, in a cell or unicellular organism), which are organized into cells, which are organized into specialized tissues and organs, which are organized into organ systems in an individual. Individuals are organized into POPULATIONS
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| Population |
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| Ecosystem |
(Population-a group of individuals of the same species). Populations are organized into COMMUNITIES (Community-a community is a collection of organisms which interact with one another). Communities of organisms make up ECOSYSTEMS (Ecosystems-include a community of organisms and the ABIOTIC (Abiotic-non-living) components of the environment in which they interact).
Many adaptations of marine organisms have to do with maintaining HOMEOSTASIS (Homeostasis-is the regulation of an organism's internal environment to maintain a stable, constant condition). Regardless of external conditions like SALINITY (PPT-parts per thousand) and TEMPERATURE (degrees centigrade).
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| Osmosis |
Many ENZYMES (Enzymes-compound proteins or conjoined proteins that are made by living cells and act as an incendiary in specific biochemical reactions) and other organic molecules are extremely sensitive to the concentration of IONS (Ion-electrically charged atom or family of atoms created by the loss or gain of one or more electrons) in SOLUTIONS (Solution-homogeneous mixture). Whenever the internal composition of a cell differs from that on the outside, substances tend to move in or out of the cell by DIFFUSION (Diffusion-is the process by which molecules move from areas of high to areas of low concentraion). OSMOSIS is the diffusion of water from areas of high to areas of low concentration. If there is more dissolved material, and therefore less water inside a cell than outside, water will move into the cell by way of osmosis. When the outside water is more concentrated than the cell, the cell loses water by osmosis to the external environment. Generally speaking, marine organisms live in a liquid medium that is more concentrated in ions than that of their internal environments. Some marine organisms regulate their salt and water balance by doing nothing at all; their internal concentrations change as the salinity of water changes.
Such organisms are OSMOCONFORMERS.
