Freckle regular use of sunblock can inhibit their development. Liver spots (also known as sun spots and lentigines) look like large freckles, but they form after years of exposure to the sun. Liver spots are more common in older people. Freckle Freckles are clusters of concentrated melaninized cells which are most easily visible on people with a fair complexion. Freckles do not have an increased number of the melanin-producing cells, or melanocytes, but instead have melanocytes that overproduce melanin granules (melanosomes) changing the coloration of the outer skin cells (keratinocytes). As such, freckles are different from lentigines and moles, which are
Face and neck development of the human embryo position and locates at the junction of the nasal cavity and the pharynx. The nasal septum grows as a downgrowth from the merged nasal prominences and fuses with the palatine process between the ninth and eleventh week. Finally, the superior, middle and inferior conchae develop the lateral wall of each nasal cavity. Face and neck development of the human embryo The face and neck development of the human embryo refers to the development of the structures from the third to eighth week that give rise to the future head and neck. They consist of three layers, the ectoderm, mesoderm and