situated on or near outside. Beyond the limits or edges of some place, thing. external side or surface. Beyond the limits or edges of some place, thing.

affect with disease-causing organism.

each of parts into which something is or may be divided. Parts divided from the other parts of some things. divide something into separate parts or sections.

Not of the same kind; unlike other things.

difficult to understand. To have or be included as a part of something.

To block or close something.

any of class of nitrogenous organic compounds. Groups of molecules made from amino acids.

To go round continuously.

An enzyme, present in many pathogenic or symbiotic microorganisms, that catalyzes the breakdown of glycosides containing neuraminic acid..

on condition or understanding that. To make available; to supply for use.

Not made by humans; without human intervention. naturally. person having innate talent.

In physical contact with, as for support; next to.

act or process bringing change. Acts of making or becoming something else. make different.

person who is studying or has expert knowledge of one or more of natural or physical sciences. People who are trained in a science.

blood protein produced in response to and counteracting specific antigen. Substance produced by the body to fight disease.