AP BIOLOGY

Detailed explanation-1: -Both basal cell and squamous cell cancers (the most common types of skin cancer) tend to be found on sun-exposed parts of the body, and their occurrence is typically related to lifetime sun exposure.

Detailed explanation-2: -The two most common types of skin cancer are basal cell cancer and squamous cell cancer. Typically, they form on the head, face, neck, hands, and arms because these body parts are the most exposed to UV radiation. Most cases of melanoma, the deadliest kind of skin cancer, are caused by exposure to UV radiation.

Detailed explanation-3: -How can UV cause skin cancer? Too much UV radiation from the sun or sunbeds can damage the DNA in our skin cells. DNA tells our cells how to function. If enough DNA damage builds up over time, it can cause cells to start growing out of control, which can lead to skin cancer.

Detailed explanation-4: -Skin cancers are caused primarily by exposure to ultraviolet radiation (UVR), either from the sun or from artificial sources such as sunbeds. Globally in 2020, over 1.5 million cases of skin cancers were diagnosed and over 120 000 skin cancer-associated deaths were reported.

Detailed explanation-5: -The most common mutation induced by UVB is C to T transversion. Double base substitutions (CC to TT) also occur, albeit less frequently. UVA (and also UVB) radiation cause indirect damage to DNA via absorption of photons by non-DNA chromophores.