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.
The Central Dogma of Molecular Biology states that DNA makes RNA makes proteins (Figure 1). Figure 1 | The Central Dogma of Molecular Biology: DNA makes RNA makes proteins. The process by which DNA is copied to RNA is called transcription, and that by which RNA is used to produce proteins is called translation.