Photobiology & Light Science Flashcards
6 cards from real CLT practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 6 Photobiology & Light Science flashcards as text
What is irradiance in the context of light therapy?
Answer: Power per unit area (mW/cm²)
Irradiance, measured in milliwatts per square centimeter (mW/cm²), describes the power of light delivered to a surface area at any given moment.
What phenomenon occurs when light passes from air into tissue and changes direction?
Answer: Refraction
Refraction occurs when light changes speed and bends at the boundary between two media with different refractive indices, such as air and skin.
Which wavelength range penetrates the deepest into human tissue?
Answer: Near-infrared (700–1100 nm)
Near-infrared wavelengths (700–1100 nm) penetrate the deepest into tissue because they are least scattered and absorbed by superficial chromophores.
What is a chromophore in photobiology?
Answer: A molecule that absorbs specific wavelengths of light
A chromophore is a molecule capable of absorbing specific wavelengths of light, triggering photochemical or photobiological reactions.
The Beer-Lambert Law is used in light therapy to describe which relationship?
Answer: How light absorption increases with chromophore concentration and path length
The Beer-Lambert Law states that light absorption is proportional to the concentration of the absorbing substance and the path length through which light travels.
Which of the following best describes photobiomodulation (PBM)?
Answer: Use of non-ionizing light to stimulate or inhibit cellular functions without generating heat
Photobiomodulation uses low-level non-ionizing light to modulate cellular processes through photochemical rather than thermal mechanisms.