Rods vs Cones
Photoreceptors yog hom tshwj xeeb ntawm cov neurons pom nyob rau hauv retina thiab ua los ntawm plaub cheeb tsam; ib ntu sab nraud, ntu sab hauv, lub cev ntawm tes, thiab lub davhlau ya nyob twg synaptic. Lawv yog ib qho tseem ceeb los hloov hluav taws xob hluav taws xob rau hauv neural signals. Feem ntau retina ntawm tib neeg lub qhov muag muaj nyob ib ncig ntawm 125 lab photoreceptors. Cov photoreceptors tuaj yeem muab faib ua ob hom; uas yog, rods thiab cones raws li lawv qhov sib txawv. Ob hom hlwb no sib txawv ntawm ib leeg hauv cov qauv, photochemical molecules, rhiab heev, retinal faib, synaptic kev sib txuas, thiab kev ua haujlwm.
Rods
Qws receptors yog cov hlwb uas muaj cov ntu ntev cylindrical sab nrauv thiab ntau cov disks. Ntau cov disks ntau dua thiab siab concentration ntawm cov xim hauv cov pas nrig ua rau lawv nkag siab ntau dua rau lub teeb dua cones. Yog li ntawd, nyob rau hauv lub teeb tsis tshua muaj teeb meem los yog scotopic tej yam kev mob, tsuas rods pab txhawb rau lub zeem muag. Tsis zoo li cov cones, cov photoreceptors tsis kho qhov muag pom xim.
Nkauj
Cones yog cov hlwb muaj peev xwm ntawm qhov pom xim thiab lub luag haujlwm rau kev ua haujlwm siab. Tsis zoo li cov rods, cones tsis muaj ib tug neeg disks los tuav lub photochemicals. Photochemicals yog nyob rau hauv daim nyias nyias ntawm lub cell, thiab cov duab ntawm lub khob hliav qab yog txiav txim los ntawm folding ntawm daim nyias nyias. Qhov chaw folding no ua rau thaj chaw saum npoo av, uas nws thiaj li muab cov membrane ntau dua rau kev nqus lub teeb. Vim tias qhov qis qis ntawm cov xim pigments thiab tsawg dua amplification nyob rau hauv cones, lawv xav tau ntau lub teeb los tsim ib lub teeb liab kom zoo. Cov cones tau muab faib ua peb pawg tseem ceeb nyob ntawm lawv qhov tshwj xeeb wavelength; xws li, S- cone (short- wavelength rhiab cone), M- cones (middle- wavelength rhiab cone), thiab L-cone (ntev- wavelength rhiab cones).
Dab tsi yog qhov txawv ntawm Qws thiab Cones?
• Qws yog tus pas nrig, thiab lub khob yog lub khob zoo li.
• Qws muaj ntau cov duab pleev xim, qhov cones muaj tsawg dua.
• Teb cov pas nrig yog qeeb, whereas lub cones ceev.
• Qws siv sijhawm ntev ua ke thaum cones siv sijhawm luv luv.
• Cones muaj tsawg dua amplification, whereas rods muaj siab amplification vim ib quantum nrhiav tau nyob rau hauv rods.
• Tsis zoo li cov cones (tshwj tsis yog S-cones), rods teb saturates thaum me me ntawm cov xim yog bleached.
• Qws tsis yog xaiv xaiv, tsis zoo li lub khob.
• Cones muaj qis dua qhov rhiab heev thaum cov pas nrig muaj qhov rhiab heev vim muaj cov disks ntau dua thiab cov xim xim ntau dua.
• Degree ntawm spatial integration ua rau qis acuity hauv Rods thaum, siab acuity hauv cones.
• Qws yog achromatic thaum cones yog Chromatic. Li no, cones tseem ceeb hauv kev pom xim.
• Lub scotopic retina siv rods thaum lub photopic retina siv cones.
