rod cell
Retinal night vision
A rod cell is a type of photoreceptor in the retina, responsible for vision in low light.
Rods are far more numerous than cone cells and much more sensitive to light, but they don't detect color—only shades of gray.
They're concentrated toward the edges of the retina, which is why you see faint stars better with peripheral vision.
Ability to see dimly
- darknessTotal absence of light
- low-lightMinimal ambient brightness
- twilightLight after sunset
- duskDimming after sundown
moonlight · starlight · threshold · sensitivity · nocturnal · peripheral vision · motion detection · achromatic
Light-sensing tissue layer
- bipolarHaving two opposite poles
- ganglionPeripheral nerve cell cluster
- synapseNerve signal crossing point
- optic nerveRetina-brain neural connection
nucleus · terminal · fovea · periphery · macula · layer · membrane · cilium
Light-absorbing retinal molecule
- transductionSignal or energy transformation
- hyperpolarizationExcessive membrane voltage negativity
- depolarizationLoss of electrical gradient
- electrochemicalInvolving electricity and chemistry
cascade · neurotransmitter · glutamate · signal · adaptation · sensitivity · recovery · bleaching
Opposing brightness values
- grayscaleTonal range, black to white
- shadeDarkness from blocked light
- brightnessDegree of light emitted
- dimnessInsufficient illumination
silhouette · edge detection · gradation · luminance · intensity · black-white · tonal
night vision
Ability to see dimly
dusk · moonlight · starlight · threshold · sensitivity · nocturnal · peripheral vision · motion detection · achromatic · monochrome
retina
Light-sensing tissue layer
- bipolarHaving two opposite poles
- ganglionPeripheral nerve cell cluster
- synapseNerve signal crossing point
optic nerve · nucleus · terminal · fovea · periphery · macula · layer · membrane · cilium · mitochondria
photopigment
Light-absorbing retinal molecule
- transductionSignal or energy transformation
- hyperpolarizationExcessive membrane voltage negativity
- depolarizationLoss of electrical gradient
electrochemical · cascade · neurotransmitter · glutamate · signal · adaptation · sensitivity · recovery · bleaching · regeneration
light-dark
Opposing brightness values
- grayscaleTonal range, black to white
- shadeDarkness from blocked light
- brightnessDegree of light emitted
dimness · silhouette · edge detection · gradation · luminance · intensity · black-white · tonal
- cellscells, blood cells, nerve cells, brain cells, mitosis
- sensory organsear, nose, eyes, tongue, skin
- Vision Cellsphotoreceptors, cones, cone