Question

Explain photoreception; describe the structure of the photoreceptors and explain how visual pigments are activated and describe how we are able to distinguish colors

Answer 1

• Both human beings and animals have vision, which is known as the method of light of light detection. Eye contain light sensitive sells, it helps in vision. These light sensitive cells are called photoreceptors, these cell are present in the retina . It contain rhodopsin(tightly packed and presence of photopigments ), It have tightly packing nature, which create photopigment density. Rodes and cones present in the retina contain disk like structure, disk like structure of rods are closed, whereas cones are slightly opened.
• Proteins present in the Visual pigments, chromophore are present in the pocket like structure of protein. Chromophore will change it's shape due the presence of light, it will leads to the pigment activation.
• In humans both eye and brain function together for color distinguishing. Eye contain light receptors, these receptors will send message to the brain. When we look an object, light from that object enter the retina, from there, cones will respond and send signals to the brain, through optical nerve, then the brain identify the colour of that object and returns the color.