Anyone can get melasma, but it is more common among young women. Melasma often appears during pregnancy, in the second or third trimesters. Doctors don't know exactly what causes melasma, but the condition is associated with the female hormones estrogen and progesterone.
A ribosome is made of numerous proteins and RNA. Function The Golgi complex takes proteins made by the endoplasmic reticulum and exports them out of the cell as needed. It is able to keep dangerous proteins from damaging the cell which made them. It is like a packaging department ready to deliver the protein products made in the cell.
Learn about the structure and function of a ribosome: the biological superstructures that translate genetic information into actual proteins. slide 1 of 5. A ribosome is a biological molecule made of ribonucleic acid (RNA) and proteins (ribosomal proteins). The structure of a ribosome is complex, and it is responsible for making the millions of proteins that are needed by cells.