photo-, phot-, -photic +

1. The process of photosensitizing.
2. Abnormally heightened reactivity of the skin to sunlight.

To sensitize a substance, organism, cell, or tissue to the influence of light.

Oculography in which photocells are directed to the surface of the eye to record rotations.

1. The outermost visible layer, or surface, of the sun.

The layer of the sun that corresponds to the solar surface viewed in white light or the region from which light escapes from the sun into space.

2. The intensely bright gaseous outer layer of a star, especially the sun.

Sunspots and faculae are both features of the photosphere. The faculae are groups of small shining spots on the surface of the sun which are brighter than the other parts of the photosphere.

A device for monitoring the fetal heartbeat that emits a flash of light at each beat.

1. The biological synthesis of chemical compounds in the presence of light.
2. The production of organic substances, primarily sugars, from carbon dioxide and water which occur in green plant cells.
3. The fundamental chemical process in which green plants (and certain other organisms) utilize the energy of sunlight or other light to convert carbon dioxide and water into organic chemical energy.

Photosynthesis is often described as the most important chemical reaction on earth and is found in bacteria, cyanobactria, algae, and most plants.

The coupling of light energy to chemical energy is, directly or indirectly, the basis for nearly all life on earth.

Relating to, or taking part, in a process of photosynthesis.

The percentage of the total available light captured by plants that is subsequently converted into chemical energy.

An apparatus for determining the velocity of light.

The measurement of the velocity of light.

Of, pertaining to, or exhibiting phototaxis.

1. The movement of an organism in response to color or light pattern stimulus.
2. Taxis of an organism elicited in response to the source of a light stimulus.
3. In botany, the movement of a part of a plant toward or away from light sources.

1. The treatment of disease, e.g., herpes simplex, psoriasis, neonatal hyperbilirubinemia, or seasonal affective disorder, by exposure to light; especially, by variously concentrated light rays of specific wavelengths.
2. The use of ultraviolet radiation in the treatment of skin deseases.

A reference to the heat produced by radiant energy.

1. Related to radiant heat.
2. Pertaining to the heating effect of light-rays.