What is the correct order of the epidermal strata from the basement membrane to the free surface?

• A. Stratum granulosum, stratum spinosum, stratum basale, stratum corneum, stratum lucidum
• B. Stratum spinosum, stratum basale, stratum granulosum, stratum corneum, stratum lucidum
• C. Stratum basale, stratum spinosum, stratum granulosum, stratum lucidum, stratum corneum
• D. Stratum corneum, stratum lucidum, stratum granulosum, stratum spinosum, stratum basale

Answer: (C)

Verified step by step guidance

1. Understand that the epidermis is composed of five distinct layers (strata) in thick skin, arranged from the deepest layer near the basement membrane to the outermost layer at the free surface.
2. Identify the layers in order: Stratum basale (deepest layer), Stratum spinosum, Stratum granulosum, Stratum lucidum (only present in thick skin), and Stratum corneum (outermost layer).
3. Recognize the function of each layer: Stratum basale contains actively dividing cells; Stratum spinosum provides strength and flexibility; Stratum granulosum contributes to keratinization; Stratum lucidum adds an extra protective layer in thick skin; Stratum corneum consists of dead, keratinized cells that form a tough barrier.
4. Compare the given options to the correct order of the layers: Stratum basale → Stratum spinosum → Stratum granulosum → Stratum lucidum → Stratum corneum.
5. Select the option that matches the correct order of the epidermal strata, ensuring it aligns with the anatomical structure of the skin.