Cod liver oil - a potentially toxic source of Vitamin A: Hypervitaminosis A can result from ingestion of too much vitamin A from diet, supplements, or prescription medications.
This visible light region consists of a spectrum of wavelengths that range from approximately 700 nanometers (abbreviated nm) to approximately 400 nm. Expressed in more familiar units, the range of wavelengths extends from 7 x 10 -7 meter to 4 x 10 -7 meter.
The electromagnetic spectrum: Light. Visible light ranges from low blue to far-red light and is described as the. wavelengths between 380 nm and 750 nm, although this varies between individuals. The region between 400 nm and 700 nm is what plants use to drive photosynthesis. and is typically referred to as Photosynthetically Active Radiation (PAR).