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Beginning at the basement membrane and traveling toward the free surface, the epidermis includes the following layers:

a. corneum, lucidum, granulosum, spinosum, germinativum
b. granulosum, lucidum, spinosum, germinativum, corneum
c. germinativum, spinosum, granulosum, lucidum, corneum
d. lucidum, granulosum, spinosum, germinativum, corneum

User Prentiss
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Final answer:

The correct order of the epidermal layers from the basement membrane to the free surface is germinativum, spinosum, granulosum, lucidum, corneum. This corresponds to the stratum basale, stratum spinosum, stratum granulosum, stratum lucidum (only in thick skin), and the stratum corneum.

Step-by-step explanation:

The correct sequence of layers of the epidermis, beginning at the basement membrane and moving toward the free surface, is c. germinativum, spinosum, granulosum, lucidum, corneum. Therefore, the correct answer is:

c. germinativum, spinosum, granulosum, lucidum, corneum.

The innermost layer that sits on the basement membrane is the stratum basale, also known as the stratum germinativum. It contains the stem cells that divide to form new keratinocytes. As keratinocytes are generated, they move through the following layers: the stratum spinosum, where they start accumulating keratin; the stratum granulosum, where the cells continue to become keratinized and begin dying; the stratum lucidum, which is only found in thick skin on the palms and soles and consists of dead cells; and finally, the stratum corneum, which is the outermost layer composed of dead, flattened, keratinized cells that provide a barrier to the external environment.

User Alexander Volkov
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