photophosphorylation
The process in photosynthesis that converts light energy to stored energy in plants and bacteria.
photophthalmia
Ophthalmia caused by intense light, such as an electric light, rays from a welding arc, or reflection from snow (ophthalmia nivialis).
photophthalmia, photo-ophthalmia
Ocular inflammation; especially, of the conjunctiva, due to intense light.
photopia, photopic, photopic vision
1. Relating to vision with the normal eyes in bright light; for example, day vision.
2. Pertaining to vision in the light; said of the eyes which have become light-adapted.
3. Sometimes applicable to seeing what appears to be sparks in front of the eyes.
A person can recognize the transition from photopic vision to scotopic (night) vision with the disappearance of color perception, which is replaced by shades of black and white.
photopigment
1. A pigment, such as a retinal pigment, that is unstable in the presence of light.
2. Pigment involved in photosynthesis in plants which includes chlorophyll, carotenoids, and phycobilins.
photopsia, photopsy
An appearance as of sparks, or flashes, resulting from retinal irritation.
photoptarmosis
Sneezing caused or evoked by the influence of bright light.
photoptometer
A device for testing the acuity of vision by determining the smallest amount of light that will render an object barely visible.
photoptometry
Measurement of the least illumination required for eyesight.
photoreactive
Describing a molecule that gathers light and converts it into energy.
photorespiration
1. The oxidation of carbohydrates in plants with the release of carbon dioxide during photosynthesis.
2. A process in which an organism takes in oxygen and releases carbon dioxide in the presence of light, occurring during photosynthesis in conditions in which there is a low concentration of carbon dioxide and intensive levels of light.
photoretinitis
Inflammation of the retina due to exposure to intense light which may result in transient central scotoma.
photoretinopathy
(s) (noun), photoretinopathies
(pl)
A burn in the central retina of the eye from excessive exposure to sunlight; solar retinopathy: Photoretinopathy can be caused by the flash of an electrical short, or because of thermal damage by intense light which can then result in reduced visual acuity.
Photosaurus
This nomenclature (“light lizard”) is no longer recognized by scientists because they found that it described an animal that was previously given another name which is Chasmosaurus.
photoscope
A type of fluoroscope with a hand-held imaging screen.
A fluoroscope is an instrument for visual observation of the body by means of x-rays.
The patient is put into position with the part to be viewed placed between an x-ray tube and a fluorescent screen. X-rays from the tube pass through the body and project the bones and organs as images on the screen.
The advantage of the fluoroscope is that the action of joints, organs, and entire systems of the body can be observed directly.
