Grade 8Science

The DNA Damage Pathway

Trace the DNA damage pathway: UV light absorbed by skin cells can damage DNA, triggering a cellular response that, if the repair fails, leads to mutations and potentially skin cancer.

Key Concepts

What happens to the energy that isn't stopped by melanin?

It continues traveling until it hits the DNA inside the cell nucleus .

Common Questions

How does UV light damage DNA in skin cells?

UV photons carry enough energy to create abnormal bonds between adjacent DNA bases. This distorts the DNA strand, disrupting normal cell replication and potentially causing mutations.

What happens after DNA is damaged by UV light?

Cells detect damage and activate repair pathways. If repair is incomplete, the mutation persists. In a dividing cell, a mutation in a growth-control gene can lead to uncontrolled cell division — cancer.

Why is the DNA damage pathway studied in Grade 8 science?

It connects physics (UV energy), chemistry (DNA bonds), and biology (cancer) in one mechanistic chain, helping students understand how molecular-level events produce large-scale health outcomes.