retinal

(noun)

One of several yellow or red carotenoid pigments formed from rhodopsin by the action of light; retinene

Related Terms

  • isomerized
  • phototrophy

Examples of retinal in the following topics:

  • Transduction of Light

    • When light hits a photoreceptor, it causes a shape change in the retinal, altering its structure from a bent (cis) form of the molecule to its linear (trans) isomer.
    • This isomerization of retinal activates the rhodopsin, starting a cascade of events that ends with the closing of Na+ channels in the membrane of the photoreceptor.
    • Thus, the visual system relies on changein retinal activity, rather than the absence or presence of activity, to encode visual signals for the brain.
    • (a) Rhodopsin, the photoreceptor in vertebrates, has two parts: the trans-membrane protein opsin and retinal.
    • When light strikes the retinal, it changes shape from (b) a cis to a trans form.
  • Bacteriorhodopsin

    • Each chain has seven transmembrane alpha helices and contains one molecule of retinal buried deep within, the typical structure for retinylidene proteins.
    • It is the retinal molecule that changes its conformation when absorbing a photon, resulting in a conformational change of the surrounding protein and the proton pumping action.
    • Reprotonation of the retinal molecule by restores its original isomerized form.
  • Magnification and Resolution

    • The labels represent various parts of the human eye: Bruch membrane (B); choroid (C); retinal pigment epithelium (RPE); and retinal rod cells (R).
  • Development of Vision

    • The optic cup then delaminates into two layers: the neural retina and the retinal pigment epithelium.
    • It is critical for the induction of the retinal pigment epithelium and the optic nerve.
  • Perceiving Motion

    • Motion is perceived when two different retinal pathways, which rely on specific features and luminance, converge together.
  • Other Infectious Eye Diseases

    • Cytomegalovirus retinitis, also known as CMV retinitis, is an inflammation of the retina of the eye that can lead to blindness.
  • Tissues and Aging

    • The labels represent various parts of the human eye: Bruch membrane (B); choroid (C); retinal pigment epithelium (RPE); and retinal rod cells (R).
  • Antiviral DNA Synthesis Inhibitors

    • It is also used to treat cytomegalovirus infection (CMV) and specifically CMV retinitis.
  • Perceiving Depth, Distance, and Size

    • When an object moves toward an observer, the retinal projection of the object expands over a period of time, which leads to the perception of movement in a line toward the observer.
  • Resolution of the Human Eye

    • Initial dark adaptation takes place in approximately four seconds of profound, uninterrupted darkness; full adaptation, through adjustments in retinal chemistry, is mostly complete in thirty minutes.
Subjects
  • Accounting
  • Algebra
  • Art History
  • Biology
  • Business
  • Calculus
  • Chemistry
  • Communications
  • Economics
  • Finance
  • Management
  • Marketing
  • Microbiology
  • Physics
  • Physiology
  • Political Science
  • Psychology
  • Sociology
  • Statistics
  • U.S. History
  • World History
  • Writing

Except where noted, content and user contributions on this site are licensed under CC BY-SA 4.0 with attribution required.