031 How Rods and Cones respond to Light

Рет қаралды 435,713

13 жыл бұрын

www.interactive-biology.com - In this episode, I go through the process of how rods and cones respond to light. I use Rods as an example and show how Rhodopsin, Transducin and Phosphodiesterase are involved in the process. Enjoy

Пікірлер: 249

@InteractiveBiology 12 жыл бұрын

@GoldenPhoenix223 Glad to know the video helped. Stay tuned for more Biology videos coming very soon!

@laurenhiew1937 7 жыл бұрын

Really appreciate Leslie making all these videos. It helps me in my study of optometry courses and i have better understanding. It's very helpful for those student that lack of imagination. this video just help me to have a clear view and better understanding of the parts and structures

@sarahbritton7431 6 жыл бұрын

this was so well explained. There's hope that I might start to understand all of this. Thank you!

@madihasidiqi3167 4 жыл бұрын

You helped me get a distinction for my Advanced Physiology unit. God bless you! Thank you!

@Kenpow93 11 жыл бұрын

Excellent video series. Not certain why persons are being so critical, when they are clearly made to give students a general understanding. Thanks, You've helped sooo much!

@InteractiveBiology 12 жыл бұрын

@bizz76 I'm sorry, but Leslie won't be able to answer your question as he is busy with a lot of stuff. He'll be making more Biology videos for the site though tackling more systems and other topics, so stay tuned for more! :)

@cherylc6959 10 жыл бұрын

Nice video. I'm an ECE student doing biophysics. your videos really gave me insights into biological processes.

@joinmebowser9000 12 жыл бұрын

@InteractiveBiology Can't wait for that video. I remember this video was why I subscribed. You really saved my day!

@InteractiveBiology 13 жыл бұрын

@joinmebowser9000 What you see in this video is what happens in response to light. So light enters, hits the rods, and then this process (shown in the video) happens. It's very similar in the cones, but uses different pigments (not rhodopsin).

@thealmassi1 11 жыл бұрын

Very coherent, well explained, good diagrams, very good breakdown of the processes. Only one mistake, though a major one and basic still does not take away from what a great video this is. Thanks!

@amila_ 6 жыл бұрын

My professor posts really vague notes and I had no idea what's actually happening and this was so helpful.

@DJPoloMan 11 жыл бұрын

Great Video. Thanks for your effort and time creating this!

@GoldenPhoenix223 12 жыл бұрын

Great video, thanks! Helped a lot for my Systems Neuroscience exam.

@sid123453 11 жыл бұрын

Sir I am very very thankful to you for clearing my concepts. Can you tell me if you have any video made on sympathetic and parasympathetic response.

@dsbllr 13 жыл бұрын

This is really really good, keep making these videos. This helps a lot, because reading the textbook on stuff like this gets really wordy.

@mrthebest2716 Жыл бұрын

12 years ago and only 1 like lol

@Shaqifaziz 10 жыл бұрын

Very clear and helpful! Thank you so much.

@dsbllr 13 жыл бұрын

@InteractiveBiology What are you planning to make your next video about ? I am asking because I have physiology right now and so far you have covered similar concepts. If that continues on I will have to check back more often.

@veronikav3671 9 жыл бұрын

Thanks so much for this video, it has been so helpful.

@dr.bangura4722 Жыл бұрын

My professor referred me again to your meaningful contents...Thanks a lot,Leslie.

@InteractiveBiology Жыл бұрын

Make sure to thank your professor for me 😃

@dr.altamashkhan9187 8 жыл бұрын

Got little confused at cGMP gated channels point...but then gradually I got it. thanks you. Dr.Shams from Pakistan

@Satchyvaladichi 12 жыл бұрын

Great video! very simple explained. It helps me to understand my medical study about the eye. Thank youuuu soo much.

@bookishangie 8 жыл бұрын

This was the one part of our unit that confused me so much (prof went through it super fast) thank you for this, it's helped me understand more. Thank you!!!!!

@MrHassanleb 12 жыл бұрын

u r great man...i really was in mess cramming of info worthlessly...know i understand tomorrow i have test..u've saved me..thanks!

@yacchan1210 9 жыл бұрын

thank you SO much from japan! that was very helpful!

@macropusrufus8207 7 жыл бұрын

awesome! Now I can understand better about this topic. Clear and easy to understand!

@tessa7403 11 жыл бұрын

im going to pass this section of my pscyh exam thanks to you

@joinmebowser9000 13 жыл бұрын

@InteractiveBiology Thanks for the answer. Well I think that kinda answered my question, but I'm still a little bit confused. So the light enters our Rods at night, or in dark places, and then the procces begins, or does Rhodopsin first goes in contact in transducin at night. You helped me with some of the question, but in just 10 hours, I should tell something about Rods and Cornes. People in my class always puts "?" on everything (just like I do) I'm reallly glad I found your channel Subbed:)

@mastertea8996 7 жыл бұрын

Nicely done.

@sreejashaw3887 7 жыл бұрын

I have a question that you told that in presence of light release of neurotransmitter slows down.then the signal do not pass to the brain then how we have see in presence of light?how we sense it?

@jaxwar5763 3 жыл бұрын

This is perfect! Thank you!

@bhatiakaran71 12 жыл бұрын

Very simply explained... Great video...Thanx...

@michaelasdf1607 8 жыл бұрын

Really good. Had problems With the detachement of the retinal ^^

@juniecr34 11 жыл бұрын

thanks so much for your help I bet this is a very good explanation but I am so confused maybe I need to watch video more than once. Thanks again for your hard work and interest in educating the world :)

@cjesu 9 жыл бұрын

I thought the fovea only contains cones ..

@mohdasifbiotech 6 жыл бұрын

what is function of fovea.if it occurs more then what will do .that situation

@yashdeeptiwari03 2 жыл бұрын

I also Our teacher says fovea has only cones not rodes

@hassananjum3782 3 жыл бұрын

Great Work!!

@ayezageza563 5 жыл бұрын

perfectly explained THANK YOU

@InteractiveBiology 13 жыл бұрын

@joinmebowser9000 No such thing as a dumb question. Yes, we use rods to see at night, but even then - that's because light is entering our eyes. We can't see with light (even when it's relatively dark). Hope that helps answer your question.

@jennadavis3950 7 жыл бұрын

Thank you so much, love your channel! Very helpful.

@jimmiller8875 9 жыл бұрын

Thanks for the video, but you might want to correct your graph of membrane potential. Open cGMP-gated channels keep membrane potential relatively "depolarized" and permissive for glutamate release from terminal. Closing these channels causes an increase in membrane potential, not a decrease as drawn.

@dogbreath223 9 жыл бұрын

jim miller clarification, starting membrane potential is negative, so increase in membrane potential is more negative and graph, as drawn, is correct

@MarkDavidKnight 5 жыл бұрын

How would the process be in the cones? If the rods are hyperpolarized and not releasing neurotransmitters, how would it work out in the cones? Thanks!!

@joinmebowser9000 13 жыл бұрын

I just got a little question. Aren't rods them we see with in the night? Then why does the procces begin when the light comes in, and not when it stops? And sorry for my dumb question, but I just came to see about rods and cones, and I haven't seen any of your other episodes, if that can explain why I'm so confused.

@cu99460 11 жыл бұрын

Thanks you interactiveBiology.... What does 'Em' mean? just confused with the little graph at 10:30?

@mathsandphysicsmadeeasy7542 4 жыл бұрын

Which software did you use to make this beautiful video? 👍

@TheAmyk01 7 жыл бұрын

Thank you sooooo much what an amazing video!

@Cd3 4 жыл бұрын

How do you remove the other alpha with the system half reacted? Oh its always on Na+ Regens

@reotshepilekgoro464 11 жыл бұрын

Wow this video helped me a lot and i really appreciate it... GOD bless you

@samasoftley 11 жыл бұрын

Cu99460 ... Em is the membrane potential, usually measured in volts. No doubt you will have seen a graph that shows an action potential/spike before, when there is depolarisation above a threshold value due to sodium ions raising the membrane potential. On this graph, it is a similar phenomenon, but because there is less sodium ions, the membrane potential becomes lower, which is known as hyperpolatisation..hope you see this in time for when you need it, I cannot reply inline on my tablet!

@xxnaruto1234xx 12 жыл бұрын

@bizz76 Yes, we entirely use cones in bright light since there are very low cGMP levels in rods and no further hyperpolarization can be done. Also, the process is same for cones as well and in response to light, they also go through hyperpolarization. Only difference is cones have different type/s of opsins present. I think you are confusing cones with the Bipolar cells? I hope InteractiveBiology can cover a topic on Bipolar cells and their receptive field.

@thesivinisha1359 7 жыл бұрын

really a gud one...try making videos on center sorround receptive field too.

@PrasannaKumar-ho4en 4 жыл бұрын

Ain't the alpha subunit of Transducin (G protein) which gets separated on conversion of GMP to GTP , activates PDE?

@scorpion5125566 11 жыл бұрын

really informative video, good job :)

@hasdianaamirahmohdhasni254 10 жыл бұрын

i want to ask admin.... is it the neurotransmitter released is the inhibitor (glutamate) ??

@kimberlymartinez6421 10 жыл бұрын

Super helpful! Thank you!!!

@anshusingh3246 9 жыл бұрын

very helpful .. thanks . can u make videos on anatomy too please

@pacifika1012 4 жыл бұрын

Thankyou so much. This video was very helpful 😊

@amburjer8291 4 жыл бұрын

thank you, this was very helpful

@sayandeb7710 3 жыл бұрын

found it extremely helpful♥️

@audreyoliger6942 7 жыл бұрын

"attractive young lady" - I nearly choked on my coffee. Very well done, thanks!!

@joinmebowser9000 13 жыл бұрын

@InteractiveBiology I'm also glad I understand it now ;)

@ajmalss80 3 жыл бұрын

Yesterday, I am diagnosed for a ERG and confirmed that I have Cone-Rod Dystrophy... And I am here for searching for this...

@hafizrustam8422 10 жыл бұрын

u realy make biology fun thank u so much plz like this makde tuff topic easy for us

@SapnaSingh-sl7ps 3 жыл бұрын

Thankyou sir.. 🙏🙏 It helps out me a lot... 🙂🙂

@nasiryaqoob8412 6 жыл бұрын

Your voice is just like Arnold Swazniger (dont mind about the spelling) and great lecture sir !

@raitom4599 4 жыл бұрын

what role does arrestin and Rhodopsin kinase play in phototransduction?

@ClassAencounter 12 жыл бұрын

Does anyone know if there is a reaction during the rhodopsin cycle that would produce and emit light or perhaps a glow?

@Rinkal87 5 жыл бұрын

Sir , my eye vision is very low does it improve my vision with stem cell.

@SuperLLL 13 жыл бұрын

How does the retinal get back to its original position?

@InteractiveBiology 12 жыл бұрын

@Ckaotenkind Well, we're glad to know you've gained something from it. We hope you aced your test. Stay tuned because we have new Biology videos coming very soon :)

@88rampitup88 12 жыл бұрын

@mp5yourmp3 You are incorrect. While the central 300 µm of the fovea, called the foveola, is totally rod-free, there are actually some rods scattered amongst the cones in the rest of the fovea.

@hannakozak3384 8 жыл бұрын

You are great!! Thank you soo much for the video! :D

@matiasschmukler5023 7 жыл бұрын

Very interesting. This video alone prompted me to subscribe. Keep it up! :)

@Guilopes99 10 жыл бұрын

According to my teacher quoting Lodish, PDE inhibitory sites are the gama subunits and not the alpha subunits. Alpha and beta subunits are the catalytic subunits of activated PDE which convert cGMP to GMP. Can you clarify?

@jaredwong3376 9 жыл бұрын

I concur

@joinmebowser9000 13 жыл бұрын

@InteractiveBiology Yeah I understood that about they nearly have the same process. And that about the attractive young lady. Oh wait NOW I UNDERSTAND!!! I totaly misunderstood it. The normal form is when it's dark. I thought the normal form was in the day, that was why I couldn't really understand it. I was wondering how the light could stop the light, if you can say so. And now your comments make perfect sense.

@kackieedgcumbe8477 10 жыл бұрын

very helpful, thanks a lot

@InteractiveBiology 10 жыл бұрын

You're very much welcome

@parth9640 5 жыл бұрын

you according to lecture when no light present(night) cGMP gated channel is open letting in sodium and depolarise rods which then release glumate(excitatory nt) on bipolar cell then bipolar cell releases GABA (inh. nt) on optic nerve so we can not see. but when dim light present(few photons) all the opposite happens and we can see in night. but what happens in day(when lots of photon) to rods ? and please clarify lights in this vedio you mean day light or night

@dennuella 11 жыл бұрын

Bless you Sir! Thank you

@jennifervela7545 10 жыл бұрын

very helpful, thank you!

@dhruvsrinivasan8558 9 жыл бұрын

Can you please help me. I would like to know what GDA is and what GTP is

@Priyanshu917 8 жыл бұрын

This video is very useful but there should be cis retinal/ retinene instead ogf retinol. Its a bit confusing, please make me correct if I am wrong...

@samanthaopara 8 жыл бұрын

There are no rods in the fovea

@mohsinyasin6675 8 жыл бұрын

+Samantha Opara yep i agree (0.45)...only cone cells are mainly found in the fovea

@nadaid8449 5 жыл бұрын

ya in the fovea centralis there no rods only cones but in the maucla lutea there are many cones and a few of rods

@nitaigandhar7631 5 жыл бұрын

thats true

@InteractiveBiology 12 жыл бұрын

@EphraimHeinrich Hi, thank you for watching. Leslie will be uploading more videos by next year. He just might or might not tackle this topic again with more clarifications. Please stay tuned for more!

@austmcc 11 жыл бұрын

I don't think it will complicate things, just chemically speaking there is a big difference and writing the wrong one down in an exam is not the best. If you just kept it as retinal throughout the video, then i would consider it a general introduction and wouldnt criticise. in all fairness, its great that things like this are available on youtube and that people take the time to upload them. i would keep it as retinal for simplicity and only mention the retinol etc in a more in depth video.

@sowmyas8411 6 жыл бұрын

Very good video. . But what happens in cone? . Tel about cone transduction.

@nikhildesai3101 11 жыл бұрын

nice video........... good job

@PAUTNETER 8 жыл бұрын

Thank you so much!

@madjack443 10 жыл бұрын

At about 9:50 you mentioned a "depolarization" from cGMP gated-ion channels. but you also said that Na+ ions were leaving the cell, wouldn't this cause a hyperpolarization?

@JimHesnen 10 жыл бұрын

Yes it will cause Hyperpolarization, but the moment it happens, this polarization of membrane will release neurotransmitter into the synapse of the rods membrane and the bipolar neuron, thus impulse is generated to the occipital region for vision processing.

@Guilopes99 10 жыл бұрын

depolarization from cGMP causes Na+ to enter the cell via the ion-channels, not to exit

@JimHesnen 10 жыл бұрын

keep in mine that the bipolar neuron has on-center and off-center which works differently

@madjack443 10 жыл бұрын

I always thought that the rods and cones' resting state was a depolarized membrane potential, and they are constantly releasing NT onto the bipolar cells. Once visual transduction processes have been performed that constant stream of NT is shut off creating a change in membrane potential of the bipolar which can code for ON or OFF. (NT = neurotransmitter)

@SamiK951 10 жыл бұрын

Madjack Your last comment is correct. Some Na+ ions are always leaving the cell, whether it's light or dark, due to the ongoing activity of the Na+/K+-ATPase, which pumps Na+ out and K+ in. On its own, this would cause the membrane potential to be set at approximately -70mV (which is the case for many neurons). However, in photoreceptor cells, the cGMP-gated Na+ channels allow Na+ ions to diffuse into the cell faster than they are being pumped out by the sodium-potassium pump, causing the cell to be depolarised in the absence of light.

@sanyadj2379 7 жыл бұрын

Thankyou so much for this...

@seramichelle11 8 жыл бұрын

Fovea centralis only contains cones.

@AARONHOLDEROFFICIAL 8 жыл бұрын

it's 11 cis retin the rhodopsin is attached to the transducin before the light hits.

@InteractiveBiology 13 жыл бұрын

@Malikorous LOL. Not sure, but glad you are finding value in them. All the best!

@terachith1565 7 жыл бұрын

I want to know if that occur in dim light right not bright one in rod!! I mean this suppose to occure at dark enviroment plz help me undersand it

@InteractiveBiology 13 жыл бұрын

@dsbllr0 These are the next topics that I'm trying to cover: I will finish deal with visual processing and then go to auditory processing. Once that's done, I'll probably move on to the muscular and then the circulatory system. I'm basically dealing first with the different systems in the body, and then expanding to other things within biology, and I'll be posting them regularly. Make sure to subscribe and also stay tuned to my website as I add more resources.

@tammybush3162 8 жыл бұрын

Isn't it cis-retinal not retinol? Great video and very clear!

@EmmanuelKorankye5020 8 жыл бұрын

Waoooooo!!!!! Where have you been man. Thats soo helpful. Much appreciated

@malanigamage2169 6 жыл бұрын

Emmanuel Korankye yeah💓

@MsTommyknocker 9 жыл бұрын

I dont understand. Wouldnt the rod be releasing inhibitory neurotransmitters in its "on" state since the bipolar cell is off when the rod cell is on??

@justinas1298 9 жыл бұрын

there are two types of bipolar cells, "ON" and "OFF". in the light, rods release inhibitory neurotransmitters, which activate the "ON" bipolar cells but inhibit the "OFF" cells, so the response is only sent through the "ON" route. in the dark, it's vice versa. rods don't release any more inhibitory neurotransmitters, "ON" cells are inactive, but "OFF" become depolarized and the signal is sent out through "OFF" route. now, bipolar cells can't affect rod cells, but horizontal cells can. they connect between rods and participate in lateral inhibition, a process when a neural signal from one rod cell is enhanced by hyperpolarising another rod cell next to it.

@InteractiveBiology 13 жыл бұрын

@SuperLLL Once the energy from the photon is used up, the retinol goes back to it's original configuration. It takes energy from the photons to keep it in the modified configuration.

@asgher07 12 жыл бұрын

simply awesome

@traxxasbro5604 4 жыл бұрын

*Retinal (not retinol)...the molecule is an aldehyde, not an alcohol

@InteractiveBiology 12 жыл бұрын

@yazzhopper864 I know, it makes it all easier, right? Glad to know you find some value in it. We have more Biology videos in the site. Stay tuned for new ones coming very soon! :)