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What is Principal cell of epidermis: and explain in detail?
Ans. (c) KeratinocytesRef : Fitzpatrick 7th ed. /100CELLS OF EPIDERMIS* Keratinocytes: These are considered as the principal cells of epidermis. They proliferate in basal layer and differentiation occurs in spinosum and granulosum layer which further matures fully and dies in corneum. (keratinocytes are present in all 4 layers of epidermis)* Melanocytes and Merkel cell: Present in stratum basale.# Melanocytes synthesize melanin pigment and transfer to keratinocytes# Merkel cells for touch sensation. Aka touch cells* Langerhan cell found in stratum spinosum and act as antigen presenting cells (macrophages).# They contain tennis racquet shaped granules aka Bierbeck granules