Results for “organism”

prokaryote

Normally unicellular organisms possessing cells without a membrane-bound nucleus.

protein skimmer

Mechanical device used to remove organic compounds in marine aquaria via the process of foam fractionation.

Used in 1 profile

protozoan

Any member of a diverse group of unicellular eukaryotic organisms including amoebas, ciliates, flagellates, and sporozoans. Also spelled protozoon.

rear

To breed an organism and play some part in caring for the young.

Used in 62 profiles

refugium

A region that has remained unaltered by a climatic change event and provides an area where relict species are able to survive; in aquaria the term is used to describe an aquarium or other container maintained within a larger system, usually displayed alongside or beneath it, where certain organisms that would not survive in the main aquarium can be maintained.

reproductive isolation

The inability of two or more groups of organisms to interbreed due to the existence of geographical, behavioral, physiological, or genetic barriers. These can be further separated into those being active pre- or post-copulation.

respiration

The process by which an organism acquires the oxygen necessary for metabolism and expels excess carbon dioxide formed during energy-yielding reactions.

Used in 7 profiles

rheophile

An organism living or thriving in running water.

Used in 71 profiles

rheotaxis

Movement or orientation of an organism towards, into (positive rheotaxis) or away from (negative rheotaxis) a current of air or water

rhizoidal

Of or relating to a rhizoid or rhizoid-bearing organism.

RNA

Abbreviation for ribonucleic acid, a single-stranded, self-replicating genetic material comprised of a chain of nucleotides. Present in nearly all living organisms, and replaces and performs the role of DNA in some viruses. Particularly important in protein synthesis and sometimes in transmission of genetic information.

saprophagy

Feeding on dead or decaying organic matter.

scavenger

Animal feeding on dead or decaying organic matter.

Used in 19 profiles

selective breeding

Intentional, normally controlled breeding of organisms favouring desirable or improved traits. Common in the ornamental fish hobby and industry.

Used in 4 profiles

serra

A small, sharp notch or organ shaped like the tooth of a saw.

Used in 6 profiles

skeleton

In vertebrates, the internal structure composed of bone and/or cartilage that supports the soft tissues and protects the internal organs.

Used in 15 profiles

spawn

The eggs of fishes and other aquatic organisms; to deposit and fertilise such eggs.

Used in 673 profiles

sting

Sharp, pointed, piercing organ normally formed from a modified spine and secreting venom from glands at its base when present in fishes; the act of stinging; the wound or pain caused by stinging.

Used in 110 profiles

stolon

A horizontal connection between organisms, e.g., the branching, stem-like structure seen in some lower animals and more commonly, higher plants.

stressor

Chemical or biological agent, environmental condition, external stimulus or event that causes stress to an organism.

Used in 1 profile