Chromosome Numbers During Division: Demystified!

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  • Опубліковано 3 гру 2024

КОМЕНТАРІ • 914

  • @AmoebaSisters
    @AmoebaSisters  4 роки тому +294

    We like to pin clarifications at the top of our videos. We've learned there are differences about how one defines the term 'centromere' and some more updated versions of textbooks are using a more detailed definition of molecular sequences making up the centromere - which means that when you have a chromosome with replicated chromatids - you could consider it to have two centromeres (one per sister chromatid) bound together in a region. Many textbooks still refer to a single centromere on a chromosome with two fully attached sister chromatids - as they are considering the complex where the centromeres are attached - and then they show fully separated sister chromatids with their own centromere. While we have done this as well by illustrating one centromere per eukaryotic chromosome, we think it is important to understand this complex is where they are joined with cohesin in the case of sister chromatids - as well as also understanding how the definition of centromere has changed. You can see a conversation about this here: twitter.com/AmoebaSisters/status/1192621868605419520 It would have been better for us to have said "centromere region" - and again, when sister chromatids are attached at the centromere region, it is still counted as one chromosome. If we update this video, we'll probably feature this information about the centromere and we'd like to improve our drawing to show the bound centromeres.

    • @vrushipatel5348
      @vrushipatel5348 4 роки тому +5

      Amoeba Sisters I just wanted to say, I love your videos! They’re so helpful!

    • @banana697
      @banana697 4 роки тому +3

      Okay thanks! I did very well on meiosis and I got a 90 on it! All thanks to you that I got it!

    • @ananyanoronha632
      @ananyanoronha632 4 роки тому +2

      Thanks for clarifying

    • @kanimozhi7552
      @kanimozhi7552 4 роки тому +1

      Thank you so much sisters.
      This was so helpful

    • @미유냠
      @미유냠 4 роки тому

      I hate this vid =-=

  • @tomwright6315
    @tomwright6315 7 років тому +3207

    I don't think you understand how useful this video was, no teacher or book has ever told me that you would count chromosomes from the centromere and i was stuck for so long trying to understand the diagram in the book

    • @JWentu
      @JWentu 6 років тому +114

      THIS was EXACTLY my problem too!!! are they doing that on porpouse, hiding info that is useful for understanding biology??

    • @kalyanitewari
      @kalyanitewari 5 років тому +22

      SAME PINCH
      I AM DOING THIS CHAPTER FOR SO MANY HOURS AND NOW I GET IT😅😅 ALL THANKS TO THE AMOEBA SISTERS

    • @logerilo5950
      @logerilo5950 5 років тому +4

      Yeah man, same here

    • @tommyshelby12
      @tommyshelby12 5 років тому +3

      Same :)

    • @SEB1991SEB
      @SEB1991SEB 5 років тому +38

      I know, it's ridiculous! Some people can be geniuses in their subject but complete idiots when it comes to teaching it!

  • @beastorc55
    @beastorc55 9 років тому +729

    Just letting you know, my biology teacher shows us your videos in class daily. They really have helped explained all this to the students in our class. Keep it up.

    • @AmoebaSisters
      @AmoebaSisters  9 років тому +82

      +beastorc55 Yay, we are so happy to hear that---thank you!! :D

    • @charlenesu5601
      @charlenesu5601 7 років тому +25

      I wish my bio teacher used these. I am pretty sure the whole class would get it and stop falling asleep during lectures...

    • @tonyhines5432
      @tonyhines5432 7 років тому +5

      beastorc55 same here.

    • @elisedanielle9427
      @elisedanielle9427 5 років тому +2

      Yess couldnt agree more keep up the GREAT work:) #BFFs

    • @ilehe6887
      @ilehe6887 2 роки тому

      and after all these years, our teacher found out and started using them too :)

  • @EKD-vp3ng
    @EKD-vp3ng 3 роки тому +857

    You guys are helping even AP Bio students 😂. Honestly it seems funny how An animated cartoon of DNA is better than a APBIO textbook 😂

  • @josephworthley2191
    @josephworthley2191 8 років тому +210

    Best amoeba teacher of the year award goes to the Amoeba sisters.

  • @sudalaimani9116
    @sudalaimani9116 4 роки тому +71

    "S phase:amount of DNA per cell doubles, but no increase in number of chromosomes " this is the line which was so confusing and we used to break our heads over it. Finally understood this only after watching your video. Helps a lot! Thanks, it was just amazing!!!

  • @niania1112
    @niania1112 2 роки тому +50

    Where can I sign up to attend Amoeba Sisters University in person?!?!? You guys are literally LIFE CHANGING!! Regardless of how professors present this information... nobody thinks to explain that ONE chromosome can have ONE chromatid or TWO chromatids. This basic piece of information clarified the main source of my confusion from every genetics lecture I've listened to. Soooooo thankful and appreciative for you guys! Also, your website and resources are beautiful!

  • @ddfamf88
    @ddfamf88 5 років тому +19

    I went through high school honors biology and college biology BEFORE I ever realized that ONE CHROMATID is a chromosome AND TWO "joined" CHROMATIDS are ALSO a chromosome. No teacher ANYWHERE explained that simple concept. Once I realized that, I understood the whole concept of meiosis and mitosis (not just memorization for a test).
    1:33 - would have saved me alot of time and energy 30 years ago!
    Thank you very much!

  • @divine_potato
    @divine_potato 7 років тому +297

    THANK YOU SO MUCH -- I FINALLY GET IT
    It took me 8 videos to find out the numbers.
    The charts you did at 3:44 and 4:30 are the MOST helpful numerations I have seen thus far.
    Thank you thankyou thankyou !!!!!

    • @cyka6blat989
      @cyka6blat989 Рік тому +1

      Yup

    • @thedog5k
      @thedog5k 6 місяців тому +1

      Bro the 4:30 chart made EVERYTHING make sense

  • @orangecone333
    @orangecone333 7 років тому +21

    This video and the one on Meiosis have helped me so much in my college Biology class. Sometimes it's so wordy in college and you need something simple to explain. Your illustrations are so great Petunia!

  • @kendallr731
    @kendallr731 4 роки тому +141

    I managed to graduate from college without understanding this. Now I'm studying for the MCAT and this just made everything make soooo much sense. Thank you!

    • @hanniadimas8664
      @hanniadimas8664 3 роки тому +7

      It’s been a year. How’d the MCAT go? Curious to see what you majored in.

    • @nataliekwok14
      @nataliekwok14 3 роки тому +2

      @@hanniadimas8664 SAME lol

    • @thecrazyone3774
      @thecrazyone3774 2 роки тому

      How’d it go?!

    • @mekanwoke6968
      @mekanwoke6968 2 роки тому +7

      This is literally how I have been feeling over the past few weeks of studying for the MCAT. How did I make it through college and grad with a 3.84/4 without understanding this!

    • @Thewisdomacademy1998
      @Thewisdomacademy1998 2 роки тому

      haha. my NMDACT test is 2 months from now and same is the case with me .

  • @eg_e16
    @eg_e16 Рік тому +6

    WORDS CANNOT EXPRESS HOW MUCH GLAD I AM THAT THERE ARE PEOPLE LIKE YOU BETTER THAN MY BIOLOGY TEACHER THANK YOU SO MUCH AMOBEA SISTERS

  • @masonics2927
    @masonics2927 6 років тому +19

    I’m learning this in Biology and I understand and learn more in a few min from watching your vids then an hour a day listening to my teacher talk

  • @yarenot9878
    @yarenot9878 8 років тому +86

    Thank you so much. I have an exam in 2 days and you saved me!

    • @ElinaCreates
      @ElinaCreates 8 років тому +5

      Same here,got one tomorrow.

    • @Billy-cr5tx
      @Billy-cr5tx 5 років тому +1

      praise melchizedek I have mine tomorrow

    • @gloryxo3459
      @gloryxo3459 5 років тому +1

      mine is tomorrow 😢😹

    • @kenm2595
      @kenm2595 4 роки тому +2

      my ap exam is in 3 days

    • @kenm2595
      @kenm2595 4 роки тому +2

      im finna get a 1 😜

  • @RoboThot711
    @RoboThot711 5 років тому +6

    I'm a senior in college with a biology major and I'm JUST NOW learning that there are 92 chromatids and you count chromosomes by the centromeres. Thank you so much for this!

  • @ameliac8847
    @ameliac8847 2 роки тому +9

    I am a teacher and I still get muddled up by this! Perfect video to show my A-level class. THANK YOU.

  • @bharathhari6788
    @bharathhari6788 4 роки тому +15

    Thank you so so so much !!!! I was breaking my head over this for 3 years long , came across 4 different teachers and no one ever explained me this !!!! Thank you so much amoeba sisters . You are making free and valuable videos for all students education and making learning in a fun way too . Lots of Thanks from India 👍👍

  • @bognabachowska6161
    @bognabachowska6161 7 років тому +9

    U're a freaking genious teacher. I could never get how this numbering goes and now it just made sence. Thank you!

  • @JMP147
    @JMP147 6 років тому +75

    THANK GOD for this video and for clearing up the definition of a chromosome/chromatid and explaining meiosis as chromatid going from 92 to 46 to 23. This makes so much more sense than the classic textbook explanation of 2n -> n -> n !!

  • @ian10432
    @ian10432 Рік тому +2

    I have an entrance exam for college this week. This is the most comprehensive and creative expanation of meiosis on all videos that i watched in youtube! Thank you so much

  • @hellokitty78ify
    @hellokitty78ify 9 років тому +282

    How ironic is it that I am just reviewing this for physiology and I understood the mitosis and meiosis process but I never understood how it got from 46 to 92 to 46 in each cell in mitosis. Lol

    • @elo14puff06
      @elo14puff06 9 років тому +1

      Same

    • @kelseyb.5706
      @kelseyb.5706 8 років тому +8

      +hellokitty78ify Its pretty simple. Theres 46, then they duplicate, then the cell splits and back to 46. Simple. Thanks +amoeba sisters

    • @kajalshaw2057
      @kajalshaw2057 6 років тому +1

      Me too

    • @shalleey
      @shalleey 5 років тому +1

      Hahaha. Relateable.

    • @a.i9395
      @a.i9395 5 років тому +11

      It begins by 46 chromosomes but double structured( since it has been replicated in interphase) then when it gets in anaphase the chromosomes are split from the centromere so it becomes 46 single structured chromosomes and the chromatid count will also be 46
      The confusion of the 92 chromosomes is because the chromosomes have split but the cell hasnt yet. So when the cytoplasm splits it becomes 2 cells have 46single structured chromosomes but prior to that as in anaphase 46 single structured chromosomes in each pole in the same cell

  • @aditimitra8040
    @aditimitra8040 3 місяці тому +2

    this 6 mins video solved my 6 year old doubt regarding mitosis and meiosis. Love you

  • @madeline5580
    @madeline5580 6 років тому +6

    This is so much more easy to understand than my notes. You students must be doing very well in your science class! Keep up the good work!

  • @cat5220
    @cat5220 6 років тому +2

    This channel is literally saving my life one video at a time

  • @melissahahn6089
    @melissahahn6089 6 років тому +5

    Thank you so much for this! I am helping my son with his 7th grade science homework. We are both visual learners. Your illustrations and wording makes it so easy to process information. We were both diagnosed with ADHD. Reading words from a page can be challenging when it comes to understanding science. You are a life safer!

  • @rabbitwhite934
    @rabbitwhite934 4 роки тому +8

    You saved me from crying my grades away because I don't understand a single thing in cell division. thank you very much!!!

  • @Laura-vv6wo
    @Laura-vv6wo 7 років тому +3

    This is the first time I fully understood the counting, thanks!

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    @Striker_Xpert 3 роки тому

    You don't know how much your channel is useful to me! I am in love with this channel

  • @anikateganju5084
    @anikateganju5084 9 років тому +4

    what my teacher couldnt do in 4 hours, you did in 5 minutes............... YOU DA REAL MVP!

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    @drumandball 7 років тому +2

    These videos are so incredibly helpful. My microbiology professor used them consistently, and I use them on my own time as well. Thank you so much!

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    @boldisordorin9010 Рік тому +14

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    @taniabgeorge1189 7 років тому +7

    I AM SO THANKFUL FOR THIS SO MANY OF MY DOUBTS HAVE BEEN CLEARED YOURE THE BEST

  • @blazefactor6849
    @blazefactor6849 8 років тому +3

    Good job Amoeba Sisters! 3/4 of 100K subs, top of the internet!

  • @sandrarise
    @sandrarise Рік тому +1

    I love this video , thank you very much ,if this video wasn’t on youtube i don’t think that any video could’ve explain it the way you did and I couldn’t have been able to understand the whole thing

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    @linc 9 років тому +98

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    @pranjalisaxena1870 Рік тому +1

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    @nehamadiwalar2730 Рік тому +14

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  • @hatchwayne2173
    @hatchwayne2173 4 роки тому +1

    I am watching many videos for my general biology class, and I just want you to know that the Amoeba Sisters is my favorite. Thank you for the content! I promise to stay curious!!

  • @fatimaa5764
    @fatimaa5764 8 років тому +5

    You explained it in a very simple and succinct way for easy understanding.Thank you so much!!!

  • @RoleX_CODER
    @RoleX_CODER 4 місяці тому +1

    My teacher never demystified this! I appreciate you because it clarified an year old query thats still not solved by our teacher

  • @edwinbarreto58
    @edwinbarreto58 7 років тому +3

    I have searched dozens of videos from a variety of experts from universities all over, but have not had any success understanding the processes of both meiosis and mitosis until I saw and studied your videos. Absolutely brilliant in its purpose of redefining complex processes and terms; thank you so much!! I will definitely spread the word about your amazing work.

  • @mowchee3649
    @mowchee3649 4 місяці тому

    no one has ever explained it like this for me, thank you so much you're a lifesaver.

  • @dr.rasyal3134
    @dr.rasyal3134 5 років тому +15

    Thank god i found this.... this concept was bugging me from 11th class... and now i finally understand this... 😇😇😇
    Thanks a LoT amoeba sister Now you are my sister Too... 😛 😆

  • @logottah6789
    @logottah6789 9 років тому +1

    My teacher shows us your videos during class and it helps us learn about science a lot better. Thank you!!!

  • @johntindell9591
    @johntindell9591 8 років тому +13

    i was very confused with the number of chromosomes until i watched this video!

  • @MyrahOfficial
    @MyrahOfficial 4 роки тому

    This is so far the best video on cell division so far.. nobody ever explained that way to count chromosomes...it literally cleared every doubt I had... that u soooo much

  • @lifesnuggets5761
    @lifesnuggets5761 8 років тому +30

    Thank you so much amoeba sisters!! I'm passing bio because of you

  • @live4today11
    @live4today11 20 днів тому

    I read my text book over and over! This answered my questions in 5 minutes. Thank you both so much!!

  • @maddijackson134
    @maddijackson134 8 років тому +6

    so helpful thank you!! I have an a-level biology exam coming up and I finally get it!

  • @miguelmolina9013
    @miguelmolina9013 5 років тому +1

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  • @r_palmeri
    @r_palmeri 9 років тому +5

    This is excellent! I'll be using it in my Human Anatomy and Physiology class. Thanks

  • @mortadhamohammad7940
    @mortadhamohammad7940 5 років тому

    I have never wrote a comment like this for any educational video ever in my life but this one really helped me cause I was sick and tired for searching about the differences between chromosomes and chromatids and their numbers
    Thank you very much

  • @mslovelee86
    @mslovelee86 8 років тому +13

    You have no idea... thank you so much for clearing this confusing numbers!!!! Thank you!!!!!!!

  • @kellyfest222
    @kellyfest222 2 роки тому

    I LOVE these videos for my 7th Grader. He is understanding this so much better by watching your videos and then re-reading his book. Thank you for making these!

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    @asianassassin1529 9 років тому +4

    Loved the video! (BTW, it's CP)

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    @vidushisharma6425 5 років тому

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    @jasminemuirragui1026 10 місяців тому +1

    As I am self teaching my self on cellular biology as I am studying for my TEAS test, this video cleared up all of my confusion, thank you so much!

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    @hkgs_knight4216 9 років тому +28

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    @xoxo.amanda09 10 місяців тому +1

    im taking biology now in high school and you guys have been saving my science grades since 6th grade ❤

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    @johntindell9591 8 років тому +12

    very helpful video! Thank you very much

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    @Allugopielectricalengineer 4 роки тому

    This is one of the only few videos that was helpful to me in my entire life.

  • @abiraj2578
    @abiraj2578 9 років тому +4

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    I love your videos and they are very helpful. Can you do a cideo on primary and secondary active transport? :) Thank you.

  • @harshitasrivastava
    @harshitasrivastava Рік тому +2

    Oh my gosh thank you so much!! This literally cleared away the one doubt i had left, this was so helpful. Stay awesome!!
    As for your pinned message, to avoid confusion this is what our textbook basically says:
    Spindle fibres are attached to the _kinetochores_ of chromosomes
    And kinetochore is a small disc shaped structure at the surfacr of centromeres
    So even if there are two centromerea for two sister chromatids, we can still count the amount of kinetochores!!!

  • @lindsaym8808
    @lindsaym8808 9 років тому +4

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    you will be the one who helps me pass biology and chemistry

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    @Artoftalent07 9 років тому +1

    I love your channel. i have a biology test tomorrow and your video helped a lot. You're a life saver.

    • @AmoebaSisters
      @AmoebaSisters  9 років тому

      +Artoftalent07 Awesome---hope you aced that test! :D

    • @Artoftalent07
      @Artoftalent07 9 років тому

      +Amoeba Sisters I did. I got an A+, thanks to you. Your work is amazing and great and you cant understand how much i appreciate all your hard work just to help others out. Thank you so much.

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    @ruchikajoshi8259 9 років тому +6

    it was just amazing so nicely explainedthanks

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    @kathymania43 4 роки тому +1

    Thank you so much for simplifying this topic, not even my uni's bio department head was able to simplify this concept for us. And now the MCAT books were doing no better. So thank you guys!

  • @bunnysenpaimon6742
    @bunnysenpaimon6742 7 років тому +6

    0:21 Is legit me right now. I'm trying to do my biology homework and have been staring at my book and haven't gotten anywhere before I gave up and decided to call this up...

    • @uhh.7jjbhg
      @uhh.7jjbhg 7 років тому

      eri139 I hope you got it finished

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      @peesnlav 6 років тому

      You must've finished it by now. It'd been a year

  • @lilasianequation1813
    @lilasianequation1813 3 роки тому +2

    All these people that commented 4-6 years ago about how helpful this was are now adults, life keeps moving
    Before you know it your an adult with responsibilities
    i wish everyone in this comment section to live a long successful life

    • @christiankyleacbang9439
      @christiankyleacbang9439 3 роки тому

      Hello can i ask a question?a mosquito has 3 pairs of chromosomes.in meiosis 1,how many homologous chromosomes are there in the prophase 1?

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    @randellaustin4066 9 років тому +7

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    • @AmoebaSisters
      @AmoebaSisters  9 років тому +2

      +randell austin Thank you, so glad to hear this! :D

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    @thatweirdgirl8734 9 років тому +5

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    @Michael-tv4kp 9 років тому +4

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    @avafernandez1767 Місяць тому

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    @Lofi_deoxyribonucleicacid 7 років тому +74

    is anyone watching this during 2017

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    @selaheats_ 8 років тому

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    @anabeatrizlinhares3762 4 роки тому +15

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    @gabewaters405 9 років тому +28

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      @AmoebaSisters  9 років тому +18

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    @willow2893 7 років тому +1

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  • @junefreund9451
    @junefreund9451 6 років тому +4

    5:33 I ACTUALLY CRIED

  • @k.a.chandrasekharan3290
    @k.a.chandrasekharan3290 4 роки тому +1

    I keep coming back here to refresh my biology. Thank you so much for having my back! Keep creating such amazing content! :-)

  • @funnyferret3863
    @funnyferret3863 5 років тому +10

    You must remember Not everyone has 46 my friend was born with a extra chromosome

  • @Chelsea-gs7qj
    @Chelsea-gs7qj 2 роки тому +1

    ...somehow made it all the way to medical school without ever understanding this. Now being forced to relearn congenital diseases like DiGeorge and had to make my way back this overlooked topic as well. Thank you.

  • @sarahelo009
    @sarahelo009 6 років тому +3

    Anyone watching in 2018

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    @cadetteandromeda3981 8 років тому

    using all your videos as a reviewer for my exam. you make stuff easier to understand

  • @elijahcox6657
    @elijahcox6657 5 років тому +12

    how to become a fossil
    step one
    die

  • @conquest4783
    @conquest4783 2 роки тому +1

    Thanks for explaining something that! Wasn’t able to crack the nut until now :)

  • @skeptical_playz6142
    @skeptical_playz6142 2 роки тому

    Thank you so much. I was literally tormenting myself with trying to understand the whole chromosome thing and this single 5-minute video solved my weeks of anxiety. May the science god bless you.

  • @christianchavez2202
    @christianchavez2202 4 роки тому

    I looooveeee youuu Amoeba Sisters! I'm studying for my biology exam, your videos clarify everything perfect! Thank you.

  • @shwethasenthilkumar9091
    @shwethasenthilkumar9091 4 роки тому

    these videos are so helpful.i broke my head for three days to understand mitosis and meosis .these videos are just magic!it is up in my head already and i dont think ill forget it ever again! thank u soo much!

  • @varunmarar6771
    @varunmarar6771 4 роки тому +1

    Thank you so much!! In school they only introduced the concept of mitosis and meiosis in like half a page, and it was extremely confusing :(. But after watching your wonderful mitosis and meiosis related videos, I understood what exactly happens :) (Of course there's a lot more to study but at least I got the fundamentals) Thank you so much for your efforts!! I truly appreciate it.

  • @ashhhhhhhhhhhh07
    @ashhhhhhhhhhhh07 Рік тому

    I couldn't score well and was struggling a lot with this topic ! idk how to thank you!! YOU'VE DONE A WONDERFUL JOB AND THANK YOU SO MUCH

  • @katysveslike7555
    @katysveslike7555 5 років тому

    This video is so useful. You explained it better than any teacher or book.You saved my grade and thank you!

  • @HaileyMarieMiranda
    @HaileyMarieMiranda Місяць тому

    i've been watching your videos since 6th grade science class-- i am now a 3rd year student in university. these are literally the best videos ever!

  • @ossamahamdy6326
    @ossamahamdy6326 4 роки тому

    Thank you from Cairo, it was informative and i will follow your channel to help my son studying biology.