Lectures

Photoreceptors: Rods and Cones – Vision (PSY, BIO)

by Tarry Ahuja, MD
(1)

Questions about the lecture
My Notes
  • Required.
Save Cancel
    Learning Material 2
    • PDF
      Slides Vision SensingtheEnvironment.pdf
    • PDF
      Download Lecture Overview
    Report mistake
    Transcript
    So take a look at this image. On your left, we have a nice sunny day and you can see color and light and everything seems really great. And then we know that dust time at night where things start to get dark. On the right you notice, you don’t see color. All you see is borders and shade, but you don’t see clear color, right? And that is because of the differences between what’s being activated in terms of the rod cells versus cone cells. So color is cones and darkness and light detection is rods. So, here is an image illustrating the difference between the two. We can see where it gets its name. The rod has this rod shaped, you know, cricket or baseball bat formation. And the cone, I’m thinking ice cream cone upside-down. So they have this unique shape, which is where they get their name. And you look at where the lights, so the arrow at the top of the diagram is showing where the light interacts with these cells. And there are certain features that they share. So they both have a nucleus, they both have mitochondria which is an energy source. And they have an outer segment that contains this chemical and this photosensitive chemical or pigment is what allows us to actually engage and detect this light. So let’s get in to more detail around that. First, we’ll take a look at sort of the characteristics of rods versus cone. So rods or scotopic vision is where we have these rod cells being activated. Now in the human retina, we have about 120 million rod cells. And for sure, the MCAT exam is going to make you, force you, one way or the other, to differentiate between which one is more...

    About the Lecture

    The lecture Photoreceptors: Rods and Cones – Vision (PSY, BIO) by Tarry Ahuja, MD is from the course Sensing the Environment.


    Included Quiz Questions

    1. …response to a photon of light.
    2. …number of receptors.
    3. …type of opsin.
    4. …function.
    5. …location of receptors.
    1. With the head directed slightly off center
    2. With the head directed straightforward
    3. With the head directed straightforward through a pinhole
    4. WWith the head directed completely to the side ith the head directed extended completely
    5. With the head directed completely to the side
    1. The number of receptors involved in photopic vision is 6 million.
    2. The receptors involved in photopic vision are rod shaped.
    3. The receptors involved in photopic vision use rhodopsin.
    4. The receptors involved in photopic vision are located peripherally.
    5. The receptors involved in photopic vision are strongly photosensitive.
    1. While trying to find the light switch
    2. While on a picnic
    3. While in a store
    4. While hiking
    5. While driving

    Author of lecture Photoreceptors: Rods and Cones – Vision (PSY, BIO)

     Tarry Ahuja, MD

    Tarry Ahuja, MD


    Customer reviews

    (1)
    5,0 of 5 stars
    5 Stars
    5
    4 Stars
    0
    3 Stars
    0
    2 Stars
    0
    1  Star
    0