May 22, 2020
60
7
Status (Visible)
  1. Pre-Medical
Can someone please explain to me the difference between the two phototransduction cascades? According to my understanding, rods are used at night (depolarized) and when they are exposed to light, they get activated/hyperpolarized. This results in the bipolar ganglion cells getting depolarized, CGMP --> GMP, Na+ channels close. Is this process correct? Is this process identical to what happens in cones?

Why is hyperpolarization considered activation when you're actually turning off the rods? The terminology is a bit confusing to me.
 
Feb 5, 2020
493
332
Status (Visible)
  1. Medical Student (Accepted)
The mechanism of phototransduction cascade can be assumed the same for cones and rods in the context of the MCAT. However, the way they are processed in the brain is wildly different. Your description of the cascade sounds okay, but bipolar cells getting depolarized should be in the last part. Hyper polarization is considered activation because it allows vision to happen. There are plenty of other things that are unusual in the eye, like the ciliary body contraction, organization of capillary network, and etc. That’s why it’s so fascinating to look inside and often referred to as “the window to one’s health.” Source = I work in a vision research lab :D
 
  • Like
Reactions: 1 user
May 22, 2020
60
7
Status (Visible)
  1. Pre-Medical
The mechanism of phototransduction cascade can be assumed the same for cones and rods in the context of the MCAT. However, the way they are processed in the brain is wildly different. Your description of the cascade sounds okay, but bipolar cells getting depolarized should be in the last part. Hyper polarization is considered activation because it allows vision to happen. There are plenty of other things that are unusual in the eye, like the ciliary body contraction, organization of capillary network, and etc. That’s why it’s so fascinating to look inside and often referred to as “the window to one’s health.” Source = I work in a vision research lab :D
That's awesome! Thank you so much :))
 

Your message may be considered spam for the following reasons:

  1. Your new thread title is very short, and likely is unhelpful.
  2. Your reply is very short and likely does not add anything to the thread.
  3. Your reply is very long and likely does not add anything to the thread.
  4. It is very likely that it does not need any further discussion and thus bumping it serves no purpose.
  5. Your message is mostly quotes or spoilers.
  6. Your reply has occurred very quickly after a previous reply and likely does not add anything to the thread.
  7. This thread is locked.
About the Ads