microRNAs (miRNAs) are small noncoding RNAs that play important roles in posttranscriptional gene regulation. In animal cells, miRNAs regulate their targets by translational inhibition and mRNA destabilization. Here, we review recent work in animal models that provide insight into the diverse roles of miRNAs in vivo.icroRNAs (miRNAs) are small noncoding RNAs that play important roles in posttranscriptional gene regulation. In animal cells, miRNAs regulate their targets by translational inhibition and mRNA destabilization. Here, we review recent work in animal models that provide insight into the diverse roles of miRNAs in vivo.
Polymer Definition. A polymer is a large molecule made up of chains or rings of linked monomer units. Polymers usually have high melting and boiling points. Examples: PVC (poly vinyl chloride), polystyrene, cellulose.olymer Definition. A polymer is a large molecule made up of chains or rings of linked monomer units. Polymers usually have high melting and boiling points. Examples: PVC (poly vinyl chloride), polystyrene, cellulose.
Note: Applicable to substance macromolecular in nature like cross-linked. systems that can be considered as one macromolecule. A polymer (/ËpÉlÉ¨mÉr/) (Greek poly- , many + -mer, parts) is a large molecule, or macromolecule, composed of many repeated subunits.olymers that contain only a single type of repeat unit are known as homopolymers, while polymers containing a mixture of repeat units are known as copolymers. Poly(styrene), for example, is composed only of styrene monomer residues, and is therefore classified as a homopolymer.