a substance secreted in a glandular sac under the skin of the abdomen of the male musk deer, having a strong odor, and used in perfumery. 2. an artificial imitation of the substance. 3. a similar secretion of other animals, as the civet, muskrat, and otter. 4. the odor of musk or some similar odor.
Lens: The lens is a clear part of the eye behind the iris that helps to focus light, or an image, on the retina. Macula: The macula is the small, sensitive area of the retina that gives central. vision. It is located in the center of the retina. Optic nerve: The optic nerve is the largest sensory nerve of the eye. It. carries impulses for sight from the retina to the brain. Pupil: The pupil is the opening at the center of the iris. The iris adjusts the size. of the pupil and controls the amount of light that can enter the eye.
The retina is the photo receptive sensory layer of the back of the eye, where the optics of the eye focuses an image of what is in front of the eye. The optic nerve carries signals from the retina to the brain, which interprets them as visual images.The retina has two types of cells the rods and cones.he innermost light-sensitive membrane covering the back wall of the eyeball; it is continuous with the optic nerve 6 layers of cells that line the back of the eyeball.   â¦ One layer is sensitive to light and is the first step in turning light into vision.    These cells are a part of your brain.