Embryology Animated - the First Three Weeks

Written notes here: about-medicine.gitbook.io/emb...
Embryology animation in 3D is essential, because embryology is a difficult topic to get your head around. I've tried to make it as easy as possible. In this video I try to answer questions like: What is embryology? What happens in the first three weeks? What is gastrulation and neurulation?
Watch my Yolk Sac & Amniotic Cavity Animation: • Embryo Folding: Amniot...
#3D_Embryology
If you find the video format moves too fast, take your own pace with the written version, including annotated 3D models: about-medicine.gitbook.io/emb...
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Video Script
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In this video, we take a simplified tour through the first three weeks of embryology. Each day finishes with some etymology, because understanding of the language behind embryology is crucial to comprehending the topic well.
Week 1
Day 1
The egg is invaded by a sperm, together forming the zygote. It contains male and female pronuclei. It’s cytoplasm is surrounded by a tough glycoprotein shell.
Zygote means ‘two things joined in a close relationship’, because sperm and egg have joined to become one cell.
Day 2
First mitotic division of the zygote occurs around 30 hours post-conception, producing two blastomeres.
Blastomere means sprout-segment, because one blastomere is one segment of the developing human-sprout.
Day 3
Division continues, and once 16 blastomeres are present they are together known as the morula, which means ‘mulberry’, because this bunch of cells visually resembles a mulberry.
Day 4
Fluid enters the morula, forming an internal cavity. The morula is now known as blastocyst. From now on, we will stop drawing individual cells, and will just show the overall shapes of structures.
Blastocyst ’sprout, again, and cyst just means ‘small fluid-filled sac’, because the human-sprout now has fluid within it.
Day 5
By day 5, the blastocyst has shed its outer shell. Cells have separated into two distinct areas: the trophoblast, which develops into the placenta and will feed the embryo, and the inner cell mass, which develops into the embryo proper.
Trophoblast comes from trephein, meaning ‘to feed’, because the trophoblast becomes the placenta which feeds the developing embryo.
Day 6
Trophoblast cells break down barriers in the uterine epithelium, allowing entry of the blastocyst.
Day 7
Meanwhile, the trophoblast begins to transform into two separate parts: cytotrophoblast on the inside, syncytiotrophoblast on the outside. The latter is one cell with many nuclei.
Syncytiotrophoblast is appropriate because it is not many separate cells, it is one ‘together-cell’.
Week 2
To simplify things, and match the imagery in most textbooks, we'll remove the endometrium now, and rotate our view like so.
Day 8
The inner cell mass differentiates into hypoblast and epiblast. A space develops in the epiblast - the amniotic cavity.
Hypoblast: meaning lower ‘sprout’
Epiblast: meaning upper sprout’
Amniotic: comes from amnion, Latin for “membrane around a foetus”.
Day 9
Meanwhile, cells of the hypoblast have migrated to replace the blastocyst cavity with the primitive yolk sac. Hypoblast and epiblast together are here known as the bilaminar disc.
Bilaminar: means 'two-layered'
Day 10
By day 10, the blastocyst is now firmly implanted in the endometrium. The syncytiotrophoblast breaks into maternal capillaries known as sinusoids, effectively co-opting their blood for the developing embryo.
Day 11
On the inner surface of the cytotrophoblast, tissue known as extra-embryonic mesoderm has developed. This eventually develops cavities which form the extra-embryonic coelom. The result is extra-embryonic mesoderm adhering to cytotrophoblast and amniotic sac, where it is known as somatopleuric, and to the yolk sac, where it is known as splanchnopleuric.
Splanchnopleuric basically means ‘on the side of the visceral organs’, because this mesoderm adheres to the viscera-side (the yolk sac becomes the gastrointestinal system).
Somatopleuric means on the side of the body.
Day 13
The space known as the extra-embryonic coelom has expanded, and is now known as the chorionic cavity. The extra embryonic mesoderm linking the cytotrophoblast to the embryo is known as the connecting stalk, which will eventually become the umbilical cord.
Chorionic: from chorion, meaning ‘outer membrane of the foetus’.
Day 14
Taking a closer look at the bilaminar disc now.
Cells in the epiblast begin to differentiate and burrow underneath. This looks like a burrow down the caudal end of the epiblast. It’s known as the primitive streak, and seeing that marks the beginning of gastrulation.
Gastrulation: means ‘becoming a gastrula (a trilaminar embryonic disc - more on that in week 3)

[@tomato5920]

You did in 11 minutes what my professor failed to do in 6 hours

[@sametiskpnar8594]

This is exactly what students need. Explanation to weird words and visualization ,by not complicated but so simple yet so effective, the weird structures and their movements. Really helpful. Really good!

[@stefanlange2026]

best video I've seen so far dealing with that topic - exactly the right amount of knowledge + you get a 3d understanding what kind of cells do what and are connected to which cavity and what not, finally. thank you so much.

[@NoorFatima-xp1ww]

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[@boozy638]

the simplistic visual representation makes it so much easier to visualize and understand this topic thank you so much

[@deepanshug5727]

It is so difficult to understand these concepts in 2D you made it simple by making it in 3D.

[@francescasilviamansueto9279]

Weird 3D models, but the video is actually very easy to remember. Thanks! (explaining the meaning of every term helps A LOT)

[@wlakersnature9348]

Why weird??

[@mokie2250]

I've watched so many videos explaining this but yes, these simplified models make it so much easier to sink in for some reason

[@hamzerpanzer]

​@wlakersnature9348 Too polygonal perhaps

[@ashleylee3169]

holy crap this is the best thing i've ever seen thank you!!

[@abijeyarajan2173]

Thank you for the amazing 3D visual representation of a developing embryo. Finally understood the process without any confusions. 😄😄

[@prisce7642]

wow you have no idea of easy it is to study this in 3D!!!!! Thank you sooo much for your effort and dedication

[@zheelandara9477]

Best ever created content I have seen dealing with embryology. This 3D model is a blessing. Thank you.

[@khadijajama3367]

You literally saved me with this 3D modelling of the topic. THANK YOU

[@sametsengul5530]

Best animation in KZbin about a very hard topic to understand.As a Medical student,i have to say,thank you so much

[@sidra-tul-muntaha8334]

This video is very helpful, these geometric figures makes embryology much simpler and easier.

[@witheredsky1255]

this is by far the best video (I've written down the questions I was so confused with) and you explained it all, thanks!

[@sadartemin]

This is such a perfect video and the fact that you also provided written explanations is the best bonus. I have never understood these topics so clearly. Thank you so much for doing this. I wish you would do the same for the whole embryological process.

[@katiebrown8545]

These videos are so helpful. I have learned about this process for years and never really understood it. Thank you :)

[@bhawanameena7416]

Thank you so much for this!!!!..... really helped me to finally understand all these concepts that cannot be visualize by 2-D pictures in books!!! ♥️♥️♥️♥️

[@hanch96]

your hard work is much appreciated, this is as clear as it gets, thank you

[@pakxo.]

You just decrypted my textbook with this video. it was so difficult trying to understand what was happening in a black and white 2d small pictures

[@AhmedHassan-xd1hj]

I can't describe how glad I am with these videos you upload.. A great and useful video ❤️👏

[@mrtrance2142]

Oh gosh, thank you, Sir! Saved my life, didn't get those lectures at all.

[@Ryder2010G6]

This is wonderful! It helped me visualise what I had already learned

[@Hfekaie]

Explained my whole 2 or 3 weeks of Embryo class in 11:48 minutes, this video made it so interesting and easy to understand. Now I have actually understood this part of embryology.

[@francescadraghi2185]

That’s just brilliant! Thank you for sharing this

[@fashionfreak909]

amazing amazing amazing, im absolutely astonished at how well you explained and demonstrated!!! Thank you! lifesaving tbh

[@dana6349]

Your videos help me a lot in understanding what I’m studying and thank you for that 🙏🏼. could you please make a video about the three germ layers specifically (the mesoderm )😢

[@MagisterSpectaculi]

Lifesaver - best video I've seen in this topic! Thank you!

[@MrBramboraa]

That's hilarious! Thank you so much for this video:) I didn't expect that it could be that helpful...

[@Liboo52]

thank you so much for including etymology, that's soooooooooo helpful for remembering stuff!

[@giorgiiamanidze4232]

I'm medical student, have dealt with this topic a year ago, but it was now that i've got the concept. Best video♥️♥️

[@horia01]

Thank you so much for this, I had trouble understanding how it all looks in 3D.

[@dbzl2]

You are truly a genius, thanks so much for making this videos

[@Mukesh-pb3uv]

The Best One... We Can Ownly Imagine without much effort with the outline you provide... Which even 3d animations of events occurring can't... Weird models but very Effective...

[@quashawnchadwick2334]

I definitely need more content like this!

[@linasalih6498]

I am amazed of how u made it easy! thank u soo much

[@mahsaabidbid5775]

That was just amazing thank you so much

[@ivo3185]

This is lifesaving!!! Best video out there on the topic

[@neharao9939]

Truly amazing video. Thank you so much

[@eliblaney]

This single video helped me understand three full med school lectures

[@shankarsethuraman921]

That was a wonderful explanation !! Thank you so much

[@melancholiabitch2095]

Best embryology video ever, thanks

[@norceenhamdi]

the 3d shapes were a lil confusing at the beginning but later i found them to be very helpful and understandable! thanks!

[@nukeani2301]

The blocky polygonal 3-D models are honestly WAY better than life-like models for understanding the topic

[@parasverma005]

Please post a vedio for next three weeks of development showing how coelom and GI tract develops. This is by far the best explanation of the process. Thanks a lot

[@binujajayaseelan671]

it literally helped me so much for understanding the concept well ..... thank u so much :))))

[@ronjabmhs3276]

I hated embryology because I never understood what I’m looking at in the books. Thanks for visualizing all of this, it helped me very much!

[@labanipaul5922]

No one really no one can understand like it after watching it my all concept is clear... clearer than clear... I can't understand clearly that what happens bcz it's 3d view and lastly God gave me this channel and I am like thank god.👍👍👍👍👍😊😊😊😊😊

[@kyokopetra1217]

thanks bro it helped me a lot in clarrifying the concepts and steps of embryology :)

[@yemi3266]

The best embryology I've ever seen 🤩

[@istulover]

Amazing as always!

[@elaafadeb8775]

A lot of thanks for you and for this nice creativity 💗🌸✨

[@johnkodhek1]

This was incredible!!!! Thank you so much!

[@dr.praveenkumarbansaloncol8308]

best video ever on neural plate

[@JN-kk4nk]

Extremely clear ! Very well done ! Thanks

[@Medico1998]

best explanation in 3d!!!please make more such videos for embryology

[@juliuskrings265]

Best explanation ive heard so far, is ths the same guy that speaks headspace meditation?

[@humanbeing3177]

This is the best video. Cant thank you enough sir.

[@alessandradellongo4327]

Fantastic video! Thank you so much for making it :)

[@nachannachle2706]

Fascinating! Excellent graphics!

[@Miriyummmy]

God bless you, you saved my grade 🙏

[@ankita._.sharma]

Thanku so much. Really worth seeing. Appreciable 👏🏼

[@a.catalinaboterodds9783]

this is so very helpful. thank you!

[@team6021]

What a wonderful video, thanks mate

[@dr_zyzz]

You made my life so much easier

[@anamfatima4485]

Thank u so much.. Now I can visualize things better ❤

[@drsong8980]

Thanks from Turkey :) It helped a lot.

[@pranavireddy1605]

Wow..... simply superb 👍❤️

[@siwarbc2936]

thank you so much this is so helpful!

[@SankhaKelumDahanaggalaSKD]

Very nice video and explanation!!! 👌♥️ BTW, nice voice🗣️

[@belaliamelouka9613]

This is Just amazing thank u so much sir 💓

[@jchae9820]

wow sir ur work is fascinating keep on please!!

[@a.catalinaboterodds9783]

please make more! perhaps on brachyal arches...? you are gifted!

[@VaidekhRiyaz]

Next level concept explanation👌👌👌

[@nikhatreena2461]

Extra ordinary 🔥🔥

[@elvazhang3866]

fantastic! hope more

[@miva_poo1076]

btw you nailed this one

[@Mohammad-xe2qw]

You're amazing bro🥰

[@FeltyLP]

Can you do a follow up video with the next weeks of Embryology?

[@rishimasinha3303]

This was so useful 🌟❤️ Thank you veryyy much 😭🫂

[@user-pb8qp4vy5b]

Best video ever thanks a lot 🤝❤️

[@359tarun]

I can't thank you enough ❤️

[@yomnaelawady]

Thank u so much ❤️. That was helpful .

[@aicha20814]

That was super useful,thank u sir

[@RahulSingh-dc8js]

Nailed it💖💖💖💖💖

[@jerry-ck6is]

It an amazing vedio sir ... It's help a a lot to memorize things easily thank you so much sir

[@yashvikothari2692]

this is the besttt video ever👌👌👌👌 this made imagination too good thank u sir... 🙂🙂🙂 please keep on posting more such videos so we can learn more in this period of lock down🙂🙂 thank u again sir

[@shivakiran7465]

Thank you sir ! Your explanation was very helpful.... Can u please make a video on development of heart

[@070kshitijagarwal2]

That was so much helpful...thank u very much sir

[@Jeoninc]

Thank you so much

[@abdullahk3300]

Fantabulous

[@mohama698]

That's great, thanks so much.....😍

[@ahmeddrick7371]

Thanks a lot!!

[@ashtonsneedensequeira8803]

Cheers this indeed made embryology very much interesting 💘💘

[@Ruleofrose92]

Best video ever

[@saharasadbek1384]

amazingggg im out of word

[@riyachaudhary9049]

Best video I have ever seen please sir also make video on organogenesis from INDIA

[@soomar.7249]

my teacher should watch your videos

[@helin4232]

That’s the best video I ever seen about this object , but please what do you mean by back cord (aka) the notochord ? At 9:14

[@bjerryy]

Amazing video! Subscribed!

[@ArhamKhan-ku5cx]

best work keep it up and thanks to make this video for us . and sir plz make video on establishment of body axis . i'll be very thank full to you .