Telomere replication in eukaryotes

[@chhiringpasangvlogs2001]

The directions for the leading and lagging strand are incorrect since the leading strand is always directed towards the fork where as the lagging strands directs against the replication fork.

[@smarikasharma1299]

Leading and lagging strands are the one newly synthesized and in this video the direction of newly synthesized dna will be according to the video that's why he wrote that so he is correct actually ....

[@H.shah123]

thanks, your videos really help me.may ALLAH give you more success

[@shomusbiologyofficial]

Thank you so much for appreciating my efforts

[@Abhinav-kf4wd]

Thank u so much Shomu. Every time I have any problem I turn up to ur videos. And believe me U solve our problems like very few teachers can do.

[@shomusbiologyofficial]

Thank you so much for appreciating my efforts

[@luminouszuz5314]

Very well explained but the direction of replication is 5' to 3'. Not vice versa as you drew 😊

[@debabratalaik9296]

3' end is not short...It's is 3' overhang...5' end of new strand (where template is lagging strand) is getting short...

[@garrettp7727]

I'm obviously still learning about this but my immediate first impression was that the direction of synthesis drawn is backwards

[@symphonyrobz1617]

description for leading and lagging strands is wrong. polymerase always adds towards 3' end of Dna.

[@applush23]

Symphony Robz yea i thot the same thank God i m ryt lol

[@syed-wd8ib]

Towards 3' end of newly synthesized dna. I hope now it's clear for you guyz

[@aliskirenpril]

yeah

[@bodyspeakswithmusic1862]

Explanation is very very clear bt replication directions of leading nd lagging strand are vise versa

[@biologygeneandbiochemistry1654]

You should change direction of two streands Telomerase moving in the 5'>>>>3'

[@bidishac.8399]

Very clearly explained !

[@subhendugiri638]

The fork direction is completely wrong.

[@souravkaran6511]

U r right

[@pavanprajapati5621]

Ledding and lagging strand direction is wrong. It is basic thing ???

[@maheshs8855]

the leading and lagging strands are menctioned opposite

[@umersaleem2590]

Leading and lagging strands are wrongly mentioned.

[@sumbalsaeed8199]

its 5 to 3 prime which is leading with continuous synthesis. kindly correct it.

[@sukhendumukhopadhyay4219]

wow.....amazing sir

[@shomusbiologyofficial]

+Sanchari Mukhopadhyay thank you.

[@subarnachakraborty9135]

can you please decrease the length of your vidios without skipping the useful content? it will be very helpfull that way,otherwise the vidios are too long

[@armitairavani3120]

Directionality for leading and lagging strand is wrong. Leading strand is always synthesized towards the opening of the replication fork and the lagging strand is synthesized away from the opening of the replication fork. Careful!

[@pallempallem5556]

Sir.Exactly how many base pairs are removed from chromosomes during one single cell division ?

[@GeneticsLessons]

This video have to be deleted. Everything is messed up in this video: starting with leading and lagging strand and with explanation of 3' end elongation mechanism. Sequence of the TER is also wrong it is RNA 3'-AAAUCCC-5 corresponding to DNA repetitive sequence 5'-TTAGGG-3'

[@shomusbiologyofficial]

+Nikolay's Genetics Lessons I need to check that once. Then I will redo the video. It's old though.

[@husseinmahdi9510]

@@shomusbiologyofficial excuse me you have to review this video again and decide if you remove it or not

[@souvikhore9497]

Thanks

[@shomusbiologyofficial]

You're welcome

[@sutapadatta8305]

the orientation of leading strand and lagging strand is just opposite here. pl correct it, it infers wrong information.

[@jemimahmaria3507]

Sir, I have aquestion... Telomerase is (a)Reverse transcriptase (b)DNA polymerase (c)RNA polymerase (d)All of the above ...?

[@Abhinav-kf4wd]

RNA dependent DNA polymerase

[@Abhinav-kf4wd]

So the correct answer would be- both a & b

[@dikshitkapil4686]

the books and the text state that the problem of telomere shortening is associated only with lagging strand! but shouldnt this problem also be seen in the leading strand since it also has a primer at the 3 end

[@umersaleem2590]

Books do mention that it happens on both ends in same manner. RNA primer excision happens in leading strand also. Since if u observe that the RNA primer Excision of leading and lagging strand are opposite to each other i.e, at the two opposite ends of DNA. so the telomerase activity is performed at the both ends. This is actually how u get the telomere on the both ends of chromosome. If it would have been on one end only then the other end would be degraded by the nucleases which in physiological condition never happens as the ends of chromosome have telomere added to them.

[@sudhanvaddixit7141]

What bad can happen if the DNA replication does not occur at telomeres of chromosome ? List any 5 Changes.

[@hos5043]

so does that mean that telomere in humans dont actually gets shortened?

[@umersaleem2590]

yes they do get shortened but the mechanism has not been described here. I can explain u that. contact me [e-mail]

[@fasihakhan5319]

great , love to learn by you,

[@avochristos7834]

Thank you for the explanation. One question, it have nothing to do with your video. Viruses only attack specific cell right, then if a virus is modified to attack a " hard to kill " bacteria, it would make a really good antibiotic right.

[@devanggondaleeya4321]

Which book you used?

[@shomusbiologyofficial]

Didn't remember now

[@TaniandSomu]

sir you are mistaken.. plz check the replication fork... leading and lagging strand.

[@aarthiragu1897]

can you please explain RNA primer excision in leading strand? though the leading strand is synthesized continuously, once RNA primer is removed in the leading strand a gap is created in that strand also right? hence a telomeric activity would be required for all ends of linear DNA right?

[@umersaleem2590]

yes the RNA primer excision happens in leading strand also. Since if u observe that the RNA primer Excision of leading and lagging strand are opposite to each other i.e, at the two opposite ends of DNA. so the telomerase activity is performed at the both ends. This is actually how u get the telomere on the both ends of chromosome. If it would have been on one end only then the other end would be degraded by the nucleases which in physiological condition never happens as the ends of chromosome have telomere added to them.

[@aarthiragu1897]

thanks :)

[@umersaleem2590]

Aarthi Ragu welcome

[@GeneticsLessons]

It is not so. Only one strand in newly synthesized DNA strand would be shortened from it's 5' end the other original strand would be of the normal size (Every new copy of DNA consist of the newly synthesized strand and OLD strand that is not synthesized in this cylce but used as TEMPLATE. So we stated with 1 dsDNA - and end with 2 dsDNA but each would be shortened only on one opposite end and only One not both. But with every new replication cycle would loose a bit from one side then from the other - this reminds first two cycles of PSR.

[@umersaleem5858]

what happens to the primer which is present at 5' in the leading strand of the newly synthesised dsDNA? When the primer is removed in the leading strand there will definitely be a 3' overhang in the parental strand because of the primer excision in the leading strand. Ain't it so? How is telomere added on both sides of DNA?

[@palikasingh1301]

Sir, well explained. But I have some doubt. The extension of telomere region occurs in every replication, right? So if every time this happens the telomere region will become lengthier instead of getting short. Is it so?

[@mr.science2831]

but the telomerase enzyme present in a cell in small amount .so it dec as age decrease.

[@amarnathsen2486]

Bahut hard

[@ChandrachurMukherjee96]

leading and lagging strands are wrongly mentioned.... leading to some confusions.....

[@shomusbiologyofficial]

+Chandrachur Mukherjee yes I am getting this same comments. Leading and lagging is mistyped there in the board. Will upload a new video on this.

[@ChandrachurMukherjee96]

ok... please post the link here for convinience... thanks you are awesime!!

[@itaihenn2106]

thanks for a great video. i still have one thing tha doesnt clear to me the telomerase works every replication ? or it is works just in the first replication ad bulding the telomere which after in the next replication will be shorter

[@aspiretobeascholarndoctor5864]

The direction of replication you have shown is not correct,,, it's the reverse of what you have shown sir

[@souravdalapati.6270]

You did not do any new video on this and you did not delete this video yet,so it is creating misconception and providing wrong information.Plz delete this video and make a new one.I like your videos and a huge fan and i hope you will do the needful.

[@shomusbiologyofficial]

+Sourav Dalapati t Elsmere replication and termination of DNA replication video will be one only. I will delete this after uploading the new one

[@aat3191]

God bless you

[@bhajan4290]

The concept of leading and lagging strand is wrong

[@nabojitkar1147]

very nice though some mistake...but thats ok

[@ymcnu2004]

OMG! it is wrong for lagging and leading strands synthesis direction. Delete this and do not give wrong information!. Replication always done from 5' to 3'. Wrong presentation!

[@shomusbiologyofficial]

+ymcnu2004 I'd I mention it 3to 5?? Please provide the time stamp

[@RitikaSiddiqui]

Shomu's Biology 1:18

[@vikarahmed6473]

concept regarding leading and lagging has been show reverse ..... please ma it correct ...otherwise delete it...

[@MUKESHKUMAR-ft2wu]

Thanks bro

[@anoopsingh7790]

Sir i think you write leading strand as lagging strand and again lagging strand as leading strand..please don't give wrong info.

[@sourik008]

Really this video has couple of wrong information..it should be corrected.

[@shomusbiologyofficial]

Please mention

[@sourik008]

@@shomusbiologyofficial I just watched your video "DNA replication in eukaryotes 4 | Replication termination and telomerase" elongation shown for Tetrahymena (TTGGGG) , its all correct and well explained. BUT in this video Firstly , you mentioned the leading and lagging strand wrong Secondly , extension of parent strand is not correctly shown as the telomerase first pair with last two or three base of the parent strand then it elongates the strand using its template RNA , after certain elongation many things can happen as the streach form G-G bonding to seal or may form loop or complementary strand may synthesis happen using RNA primer. This video is really confusing , I personally suggest you to make this video private , as many students may get confused after watching this video like me. You can do this because you have way better video than this on same topic..hope you understand.

[@عبدالله1986]

هذا الشرح يحتوي على معلومة خاطئة حول leading and lagging strand لأنه عكس بينهم في الشرح، نتمنى عدم أخذ هذه المعلومات

[@symphonyrobz1617]

and okazaki fragments are not formed in Eukaryotes but rather in prokaryotes

[@umersaleem2590]

okazaki fragments are formed in eukaryotes not in prokaryotes. Prokaryotes having circular DNA need no lagging strand. Eukaryotes have linear DNA and their is formation of lagging strand due to directionality of DNA polymerase i.e, 5"---> 3"

[@AnisurRahman-hf8mw]

Bro your direction is wrong!!!!!

[@zubariazafar1]

You are such a confusing guy OMG!

[@priyamishra-op7fm]

Worst video plz sir do not share wrong information because we trust your knowledge..

[@shomusbiologyofficial]

Mention the wrong part here.

[@priyamishra-op7fm]

@@shomusbiologyofficial Replication fork leading and lagging strand..Let me clear one thing i am not pointing out on your work i am requesting you to upload the video which is easy to understand.

[@ENFOTV]

please delete this video.a lot of students follow you. interpretation is wrong.

[@shomusbiologyofficial]

You need to explain your statement

[@ChandrachurMukherjee96]

leading and lagging strands are wrongly mentioned.... leading to some confusions.....

[@mechikaboombayah4960]

And thus our understanding is Lagging Lol