Which of the following ultra-violet radiation cause most skin disorder-
**Core Concept**
UV radiation from the sun or artificial sources is classified into three types based on wavelength: UVA, UVB, and UVC. These types of radiation interact with the skin in distinct ways, leading to various effects on skin health.
**Why the Correct Answer is Right**
UVB radiation has the highest energy and is primarily responsible for causing sunburn and skin disorders. This is because UVB radiation penetrates the epidermis and reaches the dermal-epidermal junction, where it triggers the production of reactive oxygen species (ROS) and causes DNA damage in skin cells. The UVB-induced DNA damage leads to the formation of cyclobutane pyrimidine dimers (CPDs), which are a hallmark of UV-induced skin damage.
**Why Each Wrong Option is Incorrect**
**Option A:** UVA radiation, although it can cause skin damage, is less energetic than UVB and primarily causes photoaging and skin wrinkling. UVA radiation penetrates deeper into the skin, causing damage to collagen and elastin fibers.
**Option C:** UVC radiation is mostly absorbed by the Earth's atmosphere and rarely reaches the skin. However, it is the most energetic type of UV radiation and can cause severe DNA damage if it does reach the skin.
**Option D:** None is incorrect because all types of UV radiation can cause skin disorders, but UVB radiation is the most significant contributor to sunburn and skin damage.
**Clinical Pearl / High-Yield Fact**
Recall the "SLIP" acronym to protect yourself from UV radiation: Slip on protective clothing, Slather on broad-spectrum sunscreen, Look for shade, and Plan for sun protection.
**✓ Correct Answer: B. UV-B**