Chitin

Chitin

Chitin Definition Chitin is a large, structural polysaccharide derived from modified glucose chains. In insects, fungi, and certain invertebrates and fish, chitin is found in their exoskeletons, cell walls, and hard structures. In terms of abundance, chitin is second only to cellulose.  Chitin is synthesized by organisms in the biosphere every year in excess of … Read more

Body Cavity

Body Cavity

Body Cavity Definition A body cavity is a space created in an organism which houses organs. It is lined with a layer of cells and is filled with fluid, to protect the organs from damage as the organism moves around. Body cavities form during development, as solid masses of tissue fold inward on themselves, creating … Read more

Positive Feedback

Positive Feedback

Positive Feedback Definition Positive feedback is a process in which the end products of an action cause more of that action to occur in a feedback loop. This amplifies the original action. It is contrasted with negative feedback, which is when the end results of an action inhibit that action from continuing to occur.  These … Read more

Negative Feedback

Negative Feedback

Negative Feedback Definition Negative feedback is a type of regulation in biological systems in which the end product of a process in turn reduces the stimulus of that same process. Feedback, in general, is a regulatory mechanism present in many biological reactions. By allowing certain pathways to be turned off and on, the body can … Read more

X-Ray Fish

X-Ray Fish

The Basics X-Ray Fish are small, schooling aquatic fish native to the Amazon basin in South America. In addition to being known as the Golden Pristella Tetra, X-Ray Tetra, and Water Goldfinch, they also have translucent skin that allows their organs and skeleton to be observed, much like an X-ray. The description Small, the X-Ray … Read more

Passive Transport

Passive Transport

Passive Transport Definition Passive transport, also known as passive diffusion, is a process by which an ion or molecule passes through a cell wall via a concentration gradient, or from an area of high concentration to an area of low concentration.  It’s like moving from the train to the platform of a subway station, or … Read more

Ventral Cavity

Ventral Cavity

Ventral Cavity Definition The ventral cavity, or ventral body cavity, is a fluid filled space surrounding the organs on the ventral side of humans and other tetrapods. The ventral cavity is one of two main cavities, the other being the dorsal cavity.  The ventral cavity, in humans, is actually made up of two separate cavities, … Read more

Haploid

Haploid

Haploid Definition Haploid is the condition of a cell having a one set of chromosomes. Ploidy refers to the number of copies of the genome. Humans, and many other organisms, are diploid organisms. This means that the majority of their lifecycle is spent with two copies of the genome in every cell.  Typically, haploid cells … Read more

Zooplankton

Zooplankton

Zooplankton Definition Zooplankton (pictured below) are a type of heterotrophic plankton that range from microscopic organisms to large species, such as jellyfish. Zooplankton are found within large bodies of water, including oceans and freshwater systems.  Zooplankton are drifting ecologically important organisms that are an integral component of the food chain. Types of Zooplankton The most … Read more

Decomposers in the Ocean

Decomposers in the Ocean

Because of the warmer temperatures in tropical oceans, such as the Pacific, more decomposer organisms can be found. In marine ecosystems, bacteria are the most common decomposers. In addition to fungi, marine worms, echinoderms, crustaceans, and mollusks, there are other important decomposers.  Only bacteria and fungi can decompose in the colder ocean waters since other … Read more