Keratin of skin is softer than keratin in nail because keratin in skin has
**Core Concept**
The difference in keratin structure between skin and nail is due to the presence of different types of keratin filaments. Keratin is a protein that provides structural support and rigidity to skin, hair, and nails. The type of keratin present in skin is mainly composed of intermediate filaments, while nail keratin is rich in hard keratin, which is composed of cytokeratin 6 and 16.
**Why the Correct Answer is Right**
The correct answer is due to the presence of a higher amount of moisture in skin keratin, which makes it softer than nail keratin. Skin keratin contains a higher amount of water-holding molecules, such as hyaluronic acid, which helps to keep the skin hydrated and supple. In contrast, nail keratin has a lower water content and is more compact, making it harder and more rigid.
**Why Each Wrong Option is Incorrect**
* **Option A:** This option is incorrect because the presence of a higher amount of lipids in skin keratin does not make it softer.
* **Option B:** This option is incorrect because the presence of a higher amount of melanin in skin keratin does not affect its hardness.
* **Option C:** This option is incorrect because the presence of a higher amount of glycosaminoglycans in skin keratin does not make it softer.
**Clinical Pearl / High-Yield Fact**
The type of keratin present in skin and nails can affect their texture and resistance to wear and tear. For example, individuals with conditions such as psoriasis or eczema may have altered keratin structure and function, leading to changes in skin texture and nail growth.
**Correct Answer:**
* **Option:** D. Higher amount of moisture.