Article

You, me and UV – key terms

This resource provides explanations of the key concepts encountered when exploring ultraviolet (UV) radiation – the ‘basics’ that every student should understand.

Understanding these and using our other reousrces will help answer questions such as: What actually is ultraviolet radiation? Where does it come from? What effects does it have on the Earth and on our bodies? Can we put ultraviolet radiation to good use? Use You, me and UV – introduction to see the range of resources we have.

Ultraviolet

Electromagnetic radiation having a wavelength shorter than 400 nanometres and longer than 10 nanometres. This wavelength range places ultraviolet light between the visible light spectrum and the X-ray spectrum.

Fluorescence

The emission of visible light from a substance caused by the absorption of electromagnetic radiation, such as ultraviolet or X-rays, and which stops immediately when the stimulating radiation ceases.

Electromagnetic spectrum

The complete range of electromagnetic radiation from the shortest waves (gamma rays) to the longest (radio waves).

Ozone

A toxic gas comprised of molecules that consist of three oxygen atoms bonded together.

Melanoma

A cancer of the melanocytes. Melanocytes are found predominantly in skin but also in the bowel and the eye and are responsible for skin, hair and eye colour. Melanoma is the most dangerous type of skin cancer. It is the leading cause of death from skin disease.

Skin

The outer layer covering an animal. It contains two layers of cells, the dermis and the epidermis. Skin protects against UV rays and disease-causing microorganisms.

Lymphatic system

Made of lymph organs, nodes, ducts, tissues, lymph capillaries and vessels that produce and transport lymph fluid from the tissues to the circulatory system. It is the main part of the immune system to protect the body against disease. It is not closed and has no central pump.

Lymphoscintigraphy

A method used to identify the sentinel lymph node (the first lymph node that the lymph from a tumour site drains to). A radioactive substance is injected at the site of the tumour, and the movement of this substance is followed on a computer screen.

Skin cancer

The uncontrolled growth of abnormal skin cells. If not treated, these cancer cells can spread from the skin into other tissues and organs. There are different types of skin cancer, named according to the skin cells in which they arise. Basal cell carcinoma is the most common.

Mutation

Permanent change to the DNA sequence of a gene. Mutations can be caused by copying errors in the genetic material during cell division, and by exposure to UV light, chemicals or viruses.

Published: 29 July 2008