There are nine different essential oils in RC Blend. They are listed below along with a brief description of each oil. 1  Eucalyptus globulus Essential Oil - is one of many eucalyptus essential oils.  Eucalyptus radiata Essential Oil (Black Peppermint Oil) or Black Peppermint Oil is one of many eucalyptus essential oils.
Biology: We have cones! it is a part of our eye (on the retina, in the fovea). Cone cells, or cones, are one of the two types of photoreceptor cells that are in the retina of the eye which are responsible for color vision as well as eye color sensitivity (WIKIPEDIA)
   These cells are a part of your brain. The retina is the layer of cells in the back of the eyes responsible for detecting light, which in turn allows you to see.The specific cells responsible for detecting light are the photoreceptors, more commonly referred to as rods and cones.21 people found this useful.t is the only part of the CNS that can be imaged directly.   The retina is a complex, layered structure with several layers of neurons interconnected by synapses. The only neurons that are directly sensitive to light are the photoreceptor cells.