Telomeres and cell senescence | Cells | MCAT | Khan Academy

[@rjsflorida1]

Not only the best explanation of this complex subject.........THE BEST BY FAR!!! Nothing I've seen even comes close. Well Done!

[@jacobncindyvitela5983]

Agreed!

[@AbsoluteMongoloid]

Ten minutes of clear and concise explanation. KZbin needs more people like you!

[@mrscpc1918]

I’m sure I’m not in your target audience ( retired,71 yr old disabled, damaged female) but I’m definitely in the top percentage of appreciative and impressed. As an obsessive student I know clear concise teaching when I see it. Thanks so much for joining clearly many of my previous random areas of knowledge.

[@KenzyFarid]

May Allah bless you Mum 🌹🤍

[@thirva95]

OKAY SO THIS WAS THE BEST TELOMERE VIDEO EVER!! I've been using Khan Academy from my school years, and guys you are AWESOME

[@ionniculina4532]

The best explanation I have ever heard! 👏👏🔝💯 You could even explain this to a 5 y.o. kid and he would still understand everything! You are very talented! And the fact that you explain it through visual drawings helps even more! This video is PURE GOLD! ❤💯🙏🔝

[@user-kj6xf5sc2r]

Damn, Khan. You guys are awesome.

[@AStarkofWinterfell24]

My God... i can confidently say i understood everything you taught, by the end of this video. Unlike my Cancer Biology course

[@rachelsweets]

1000Godspell wow

[@JuliaHelen777]

"I'll have to ask a non-dividing- senescent cell how does it feel these days" 😂

[@白碧鴻]

李釗 書含現在有在一起嗎

[@白碧鴻]

李釗 書含結婚照

[@江寒刀风乱]

@@白碧鴻 good comends👍🏻

[@MichaelEnglish88]

Awesome video! To quote Ted "I want to sleep a pillow of that guy's voice"

[@rbrahmbhatt1001]

You are a GENIUS AT EXPLANATION!!!!!!

[@bonniespruin6369]

Fascinating! I've been really interested in learning about the lymphatic system getting rid of these bad cells. I started rebounding exercises. There is so much to learn about the human body. Thanks for the great video!

[@muhammetmemon6963]

Awesome! Very explanatory. And you got a talent on drawing...Thank you. One question though, you know how some people age quicker than others? Could one reason be because their cells undergo more stress (chemical, radiation, and psychological stressors) which cause more cells to end up senescent?

[@huihuihuihuihuihui1]

Yes, definitely the stress is a major factor in aging. Also genetics, by that I mean that some mechanisms to cope with stress may work better or worse depending on the genes (and number thereof) that DNA carries. For example, some species have many times more genes (which are mostly just duplications) associated with DNA damage repair and thus aging very slowly: turtles. Or rarely gets cancer: sharks, elephants despite the larger number of cells in their bodies than in us humans.

[@lbgh77]

Absolutely the best explanation of telomeres and cell senescence by far! Thank you.

[@Greenthumb-420]

by far best explanation thankyou so much!! :D

[@JB-cn1if]

It’s 2022 and still the best telomere vid out there! Love you!!

[@MichaelEnglish88]

Did anyone else gasp at 10:20 "Somatic cells can develop a mutation that allows them to be express telomerase." If that's the case, then therapy could improve our somatic cells to prevent aging. He indicates that this mutation is what causes cancer. However, if we coulid control the quantity of mutations, then essentially, all effects of aging would be reversed.

[@AbsoluteMongoloid]

Yup. One other thing to note is that senescent cells will still appear and build up due to stress, radiation from the sun etc., and must be removed eventually. Another thing to add is that cells have a built in self destruct sequence built into their DNA. The eventual goal would be to maintain Telomere length, while ensuring that cells die when intended, in order to prevent the body from becoming it's own cancer.

[@Feracitus]

plot twist, cancer is our friend.

[@user_375a82]

Can I get a supplement that adds telomerase to my somatic cells? That would be cool.

[@sandrawong6787]

My understanding: Senescence: green knight,half injured but still working Telomere:the time you have left to have kids Telomerase:god like immortality potion Cancer:someone evil stole the immortality potion Awesome

[@meiluree]

ahhh thank u so much much for your information about telomeres and senescence. this was the best video ever😊

[@nicv278]

Super duper interesting! Thank you! Love your charts! 💖

[@bella2948]

You guys never fail at explaining things clearly ,bless the whole team

[@ajellyfish6357]

So basically it's like saving a file over and over and losing information

[@8023s]

You guys are awesome. Explains so much better than my grad school profs.

[@deplorabledixie2834]

You are and EXCELLENT TEACHER..I just sub'd. Thank you for being brilliant but also being able to make it simple for people that have a tough time understanding this stuff.

[@githinjikiama3777]

Finally I am able to understand this. Thank you!!!

[@olgaderose6442]

Thank you so much for this video!!

[@jacobncindyvitela5983]

Wow! This video was so CLEAR and well explained !

[@NabiilahNMajie]

Love the presentation. Very well explained. Thanks.

[@prettycool7824]

Round of applause for this vid. Thank you so much

[@ajellyfish6357]

Electrolytes are essential for aiding the cells in maintaining telomere structure. Most of us are extremely deficient in magnesium, calcium etc

[@jenya1924]

Thanku very useful....nice explanation

[@Nora-o7p]

very interesting!

[@nikitalokhande4063]

Great explanation presentation specially that graph presentation.my confusion is clear just within 10 min🤗

[@aynaz99]

I just wanted to say this was such an amazing helpful explanation! and thank you for sharing it! I am currently struggling with TRAP assay principles, (telomeric repeat amplification protocol), could you please come up with a video that explains TRAP principles like this one please? There are almost no videos out in the internet explaining that. Much obliged from Germany

[@haneeneleiwa6892]

Fabulous, amazing explanation ....thank you

[@arkanshsharma850]

perfect explanation

[@justme4023]

best video! thanks

[@mohammadahmed-ji9jq]

this work is priceless thank you kahn

[@ayseyilmaz217]

Great explanation

[@dryusufs]

Amazing. Thanks.

[@aayushipatidar9297]

Beautifully explained👍

[@riktapatel3486]

Video is very useful, thanks

[@naronganage3046]

Great video, great explanation.

[@EldanSai]

Thank you for this amazing explanation, it was truly awesome!

[@RJOHNS202]

great video mate, cleared up everything for me

[@igorgiusti2269]

So clear! Thank you

[@DrSAT-eb3cf]

Can’t be thankful enough 😃

[@alirezahekmati7632]

gold!

[@Mixal400]

thank you very much!

[@ahmedkhidr1987]

what an explaing !!

[@hontonitai7838]

very talented at drawing !!

[@Canada2760]

Very clear, concise, thank you!

[@salvadorhirth1641]

Great explanation, clear, concise! How exactly the shortening of telomeres cause the arrest of DNA replication, is one of the most important questions in biology. At first when I first read about telomeres, I imagined that successively smaller proteins or polypeptides featuring leucine (TTA encodes leucine) and glycine (GGG) could be produced if telomeres should be transcribed in mRNA; such hypothetical polypeptides could then have an effect (like alosteric inhibition) on DNA polymerases, when such molecules are small enough. Then I learned that telomeres are non-coding; anyone could teach me more about it, please.

[@bassodivo1]

Well done!

[@killianpapail9324]

so nice

[@khamikos1]

excellent.thanks

[@stellayoss8316]

wow well explained thank you

[@aimanmazloum9561]

if only i can put 1000000 likes , Thanks a lot Khan Academy

[@amals.9933]

You have an very interesting way how you share yoir information. I really love your videos because they help me with my school stuff!!!really amazing thanks 😊best video

[@ivanlaws622]

Very Good! But where is the reference material list? You have not verified any of this!

[@aadilhussain5328]

its not a plastic tip its an *aglet*

[@etvconnect]

Cool

[@dlbdlb3919]

SUPER

[@noir5160]

AGLET

[@wiggletonthewise2141]

Thank you friend

[@Chrysolite-kn3mz]

Thank you Sir.. just one question, what's the difference between replicative senescence and clonal senescence?

[@ghazalmaleki927]

very useful thank you !!!!!

[@paulodambrosfilho581]

WOW!

[@crazyindians2524]

Awsome

[@poornimasirvaiya7949]

Thanks

[@Nora-ei4ph]

Greatly appreciated 👍 🇺🇸🇩🇪 AI biotechnology for research!

[@alaechda9056]

well explained but it is true that telomerase are specific only for telomers of somatic cells ????

[@mariyakostrova3792]

Perfect

[@saintz2k7]

Brilliant explanation...what I want to know is, why at the age of 90 aren't we just one big clump of senescent cells? Do senescent cells die out to make room for new replicating cells? Aren't tissues in our bodies getting bigger and bigger as new cells are made on top of cells which have reached senescence

[@huihuihuihuihuihui1]

The presence of senescent cells may prevent mitotic cells around to divide and thus causing them to becoma senescent too.

[@mergasheleme9605]

First choice thanks

[@chaosteady]

What is the difference between normal post mitotic cell and senescent post mitotic celll?

[@pkdouyk]

EXCELLENT!!! 10x :-)

[@HEOEvgeny]

Amazingly simple and informative video. Could you please advice how to increase telomeres ? One method is to have telomerase enzym. How do I get these? Thank you so much for what you teach others.

[@roslynphillips-lookyoungfe5880]

+HEOEvgeny FINITI™ contains the only proprietary blend of natural ingredients known to safely lengthen short telomeres and maintain healthy stem cells. It also protects your DNA, telomeres, and cells from oxidative stress. FINITI™ is Jeunesse's most advanced anti-aging supplement to date. BENEFITS - Contains the only known patented nutrient shown to lengthen short telomeres in humans* - Transiently activates telomerase, the enzyme that adds length to telomeres* - Supports the delay in cellular aging, including cells of the immune system - Promotes a feeling of youthful vitality - Contains a powerful combination of antioxidants that protect our cells, DNA, stem cells, and telomeres from oxidative stress - A source of natural nutrients that help maintain our body’s adult stem cells.ladyrp.jeunesseglobal.com/en-US/finiti/

[@CalumnMcAulay]

Can you provide me with the peer reviewed research documenting this lengthening of telomeres?

[@roslynphillips-lookyoungfe5880]

+chris mcaulay I believe the information can be found with the link .ladyrp.jeunesseglobal.com/en-US/finiti/ download the PDF no obligation to order. @ the convention the Dr explained it but I'm not an MD so I hope you can get the info you need from there. If not I will inquire about getting more complete answers to your questions. Thank you.

[@CalumnMcAulay]

Thanks for this... At first I thought it was nonsense but I never realised it was ta-65 - interestingly it also contains quercetin and tocopherols which had promising results in clearing senescent cells from the body. I will look into it; I had thought about a business opportunity with this as I am fairly big on anti-ageing however the product is very expensive for me at this present time, I was going to wait for isagenix to hit the UK. I may be in touch! Thanks x

[@Miss-Defi]

Why Not Now . . i noticed you're waiting for Isagenix and wondered if you have joined? I am excited about trying the products.

[@bigguy8586]

Okay, but why would the somatic cell that mutated to express telemerase cause cancer if the cancer comes from damage to cells that don't have enough telomeres during cell replication. In other words you said that not having telomeres causes cell replication problems, but when that is fixed it causes more problems? I don't get that.

[@elhamsadventures7513]

How does telomere protect us from cancer?

[@bennguyen1313]

How does senolytics fit into this? If a cell is senescent and inactive why does the body have to kill it? Also, in eukaryotes, if a a gene is a segment of chromosome (which itself is a segment of the dna with the histone proteins it wraps around) what controls that gene function? Its shape based on the proteins attached to it? For example, if the expression of some genes (ex. sirtuin 1) can control the expression of other genes, what controls sert1?

[@huihuihuihuihuihui1]

Senolytics allow to free up a tissue space for otherwise healthy mitotic cells to replace them.

[@TheFartOnYourFace]

Very confused, if post-mitotic cells don't divide then how does their cell division capacity stay high?

[@philosophyforum4668]

So in other words, telomerase can give us long life as long as it doesn't kill us with cancer.

[@taurohkea2169]

Just when i had hope for happy cells which would stop aging... It forms TUMOR!!

[@elhamsadventures7513]

What happens if the DNA polymerase form DNA until the end??

[@zes7215]

wrg, no worry no matter what, doesn't matter, can any happy nmw

[@thefenerbahcesk4156]

What happens when top many cells senesce?

[@mykhailohohol8708]

So why dont stem cells divide uncontrollably producing tumors?

[@tejasshah738]

Can anybody tell me name of this professor?

[@faline4595]

English is not my mother language, so I couldn't really understand if is recommended to avoid it or not.

[@michelleh.7570]

are stem cells and mutated somatic cells the only cells that can develop telomerase? and why can't heart cells/neurons become senescent? do they have telomerase?

[@allybackus6104]

the drawing looks like Dexter

[@maskedmarvyl4774]

Ok, so how can I get a drum of telomerase; not that fake supplement stuff, but the real thing??

[@Zawaf]

Correction , Stem Cells undergo replicative senescence.

[@jackkrauser1763]

10:22 so when the somatic cells start to express Telomerase by mutation does this mean that the process of aging is shut down ?

[@incognitotorpedo42]

No, it means you have cancer. At least, assuming the cell has also lost some other growth controls. If the cell was healthy and also expressed telomerase, you probably wouldn't notice much, since most of aging is not driven by replicative senescence. Cells becoming senescent for a variety of reasons is a significant part of aging, but there are a number of other factors as well. Here is a description: www.sens.org/research/introduction-to-sens-research

[@tesfamichaelharegewoin7146]

why telomere shorten during dna replication?that is my question

[@huihuihuihuihuihui1]

Google for Okazaki fragments and RNA primase

[@alexsyscore]

Why would a miotic cell that develops this mutation that enables it to multiply say "infinitely" end up becoming a cancerous cell, since our embrionic cells have this already. Why would we not want this to happen to all our cells and have them be able to multiply infinitely.

[@tianzhang1294]

Please help me with one question if possible. Does the amount of SASPs production of a cell increases as this cell gets older?

[@toto-valentin]

statistically over time it will create the risk for mutation

[@peteryyz43]

How often does our DNA replicate itself?

[@gabbyrusso8296]

There are around 2 trillion cell divisions in our bodies per day, and the DNA will divide each time this occurs

[@thefunway123]

This right here is the reason for Logan's death guys

[@LE0NSKA]

I understand that stemcells actually do now this is fucking incredible.

[@UHFStation1]

I wish there was a way to steal telomerase from potential cancer cells and give it to healthy cells that will behave. Lol.

[@hayah6586]

I will ask 😂😂