**Question:** Cells as they approach towards stratum corneum shows the following features

A. Flattening
B. Thinning
C. Loss of granules
D. Increased lipid content

**Core Concept:**
The stratum corneum is the outermost layer of the epidermis, composed primarily of dead keratinocytes and lipids. As cells move from the stratum germinativum to the stratum corneum, they undergo a series of changes to adapt to the protective and barrier-forming role of this layer.

**Why the Correct Answer is Right:**
The correct answer is D. Increased lipid content. As cells approach the stratum corneum, they undergo desquamation and flattening, losing their nuclei and other organelles. This is a part of the terminal differentiation process in keratinocytes, which prepares the cells for the protective and barrier-forming role in the stratum corneum.

The lipid lamellae, mainly composed of ceramides, cholesterol, and free fatty acids, are crucial for maintaining skin barrier function. As cells in the stratum corneum lose their organelles, they increase the lipid content to form these lamellae, ensuring proper barrier function and protection of the skin.

**Why Each Wrong Option is Incorrect:**
A. Flattening is a correct feature, but increasing lipid content is specifically important for the stratum corneum.
B. Thinning refers to the decrease in thickness of the epidermis, not the cells in the stratum corneum.
C. Loss of granules typically refers to the loss of melanin granules in melanocytes, not keratinocytes in the stratum corneum.

**Clinical Pearl:**
The correct answer demonstrates the importance of terminal differentiation in keratinocytes and the role of lipids in maintaining skin barrier function. This understanding is crucial in understanding skin pathology and treatment strategies for conditions like xerosis, ichthyosis, and contact dermatitis.