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.
The word polymer literally means many parts.. A polymeric solid material may be considered to be one that contains many chemically bonded parts or units which themselves are bonded together to form a solid. Two industrially important polymeric materials are plastics and elastomers.