Chorionic villi development in Third Week - Primary, Secondary & Tertiary Villi

In this visual medical lecture, Dr. Aizaz from MedicoVisual talks about development of chorionic villi in third week. What are primary villi, secondary villi and tertiary villi. How these developmental changes paves the way towards formation of placenta.
00:00 Intro
01:00 What is the chorion
01:45 Primary villi
03:26 Secondary villi
05:00 Tertiary villi
07:14 Functions of chorionic villi and early placenta
08:30 Anchoring villi or stem villi and Absorbing villi or free villi
10:29 Review
The embryo has two balloon like fluid filled structures the amnion and yolk sac and whole this structure is floating inside the chorionic cavity.
The outer layer of chorionic cavity is also called chorion, consists of extraembryonic somatopleuric mesoderm on the inner side and cytotrophoblast on the outer side. The cytotrophoblast is further surrounded from outside by the syncytiotrophoblast.
Cytotrophoblast formed finger like projections into the syncytiotrophoblast, called primary villi. Primary villi were formed during second week of development. Embryo, embedded into uterus of its mother, is fully covered by these villi.
Now lets talk about happens to these villi during third week of development of the embryo.
Primary villi are solid finger like cords of cytotrophoblast penetrating into the syncytiotrophoblast. Some of these primary villi also branch out but they are still the solid cords of cytotrophoblast. They are called branched primary villi.
During the third week, as the extraembryonic somatopleuric mesoderm grow further. It extends its processes into the primary villi. Now the primary villi have an inner core made up of mesenchyme from the extraembryonic somatic mesoderm. At this stage, the villi are now termed as secondary villi.
In the next step, the inner mesenchymal core through vasculogenesis and angiogenesis form the vasculature inside the villus. Now we call it, tertiary villus.
With the ongoing development of chorionic villi, almost all of the tertiary villi are branched. Some of these branches are buried into the maternal endometrium. Such villi help in anchoring the conceptus into the maternal endometrium. These branches are anchoring branches or simply anchoring villi. While rest of the branches are free and called non-anchoring villi or free villi.
Between the villi, there are the lacunar spaces that are connected with maternal blood vessels. As they blood flow within this lacunar network. The free villus branches / non-anchoring villi take up the nutrients. The nutrients then flow into the vasculature of these villi. Since these free villi help in absorbing the nutrition from maternal tissue. They are also called absorbing villi.
We will discuss the dynamics of nutrients and gaseous exchange in later lectures of placenta and fetal circulation. But here we will have a brief overview.
The vasculature in the tertiary villi has an afferent arm that bring the less-oxygenated and nutrient deficient blood came from umbilical artery and the efferent arm, that take the blood after it becomes enriched with nutrients and oxygen, to the umbilical vein that take the blood ultimately to primordial heart of the embryo. Later on, as the chorion develops further and placenta develops, this system becomes much more robust and efficient by some changes into its structure that we will discuss later.
Website: www.medicovisual.com
Email: [e-mail]

[@janicefernandes1199]

This is an example of
Do not judge a book by it's cover!!!
What an amazing lecture!! Thank you. 😀

[@MedicoVisual]

You are most welcome. I am just curious what is wrong with the cover 😐

[@janicefernandes1199]

Personally, I thought it by seeing the cover that it won't be worthwhile watching this vid.
But...it proved me wrong!
Appreciated! 🤭😌😚

[@MedicoVisual]

@@janicefernandes1199 I am so glad that the video was helpful. Thanks a lot for your comments.

[@Lightway2]

Surely this lecture was the best✨

[@abhinashsharma3456]

this kind of explanation is really what i search for every topics ... you explain things so beautifully .. thank you sir !🙏

[@vi....6124]

Thank you very much, may God bless you 🦋🤍🤍🤍🤍🤍🤍،

[@Isla-bn3wk]

Thank you! Love from Saudi Arabia

[@sanjanaak5092]

An amazing, comprehensive video - thank you so much!

[@thotasupplies1213]

Excellent sir...
Even most of the obs &gyn professors too don't explain this perfectly 👍👍👍

[@ruvarasheyemue6957]

Thank you so much.
Embryology now makes sense because of you

[@MedicoVisual]

Thanks a lot for appreciation.

[@Whereirule]

THANK YOU FOR SPEAKING IN ENGLISH

[@MedicoVisual]

You are welcome.

[@Kokofunny1637]

Thanks alot doctor I am from Egypt ❤️

[@rusabbaig6851]

Brilliant

[@chipomoono6013]

Greatest of all time!

[@shubamthakur4240]

It's so helpful mind blowing you make my lecture easy thanku so much

[@sangeethajanani3804]

thank you medico visuals

[@qamar4250]

best lecture ever

[@saraaa2209]

Great work🤩❤️❤️

[@KatottoJimmy-td5hl]

Eeeh wonderful lecture

[@Beyinagba]

Thank you so muchhh! 🙏🏽

[@farheenshaik585]

This video is short and very understandable ❤️❤️thank you soo muchh sir ❤️

[@InnocentKetero]

you hold my medical degree keep doing great work

[@ridanadeem7159]

Very well explained 👍

[@husseinmud]

Thank u so much ❤❤

[@user-bo9bp9fk5t]

Thank you sir...☺️

[@mtotowaalice3615]

what a lecture😍😍😍

[@user-qv1us1qq2y]

Thankyou so much sir 😊😊

[@amiryoucef1220]

thans you very much

[@user-yk5nl7sr8s]

very good

[@sumaiya5065]

Thank you sir 😭😭😭

[@bipshadarji1989]

Thanks ☺️👍

[@najwanadirah1927]

thakyou very much sir !!! i really understand your words very well !!! love from malaysiaaa

[@tasibaislam6051]

Zajakallah khairan for the lecture. U deserve so much like

[@MedicoVisual]

Thank you so much

[@sulaimanqadri3275]

Excellent Lecture.Very well explained 👍

[@MedicoVisual]

Thanks for liking

[@MdIrshad-pf1hz]

Thank you so much 😭 I was really struggling with this villus formation ( I had read books before but didn't got much clearification , ) but after watching this I finally understood it .

[@MedicoVisual]

You are most welcome.
Also check out the visual lectures on Placenta: ruclips.net/video/7bhBUzgzC48/видео.html

[@MedicoVisual]

Interesting question. The therapeutic gene that is meant to be inserted into the patient's DNA, can be synthetically created if it's sequence is known. It is easy to find the sequence of genes online, thanks to research projects like Human Genome Project / Genomic Library. The therapeutic gene sequence can also be extracted naturally from another human's cell.

[@user-xl3cr4wi8p]

شكرا انت
يااخي ايش انت بالضبط
ابدعتتتت

[@drjyothishrocks4417]

Excellent.. Thank u

[@MedicoVisual]

Welcome 😊

[@mmu5650]

tomorrow is my 1st proffesional exam,,,,,you are helping alot.....thank you

[@MedicoVisual]

All the best

[@anwarulhaq535]

Very good explained lecture.

[@MedicoVisual]

Thanks for liking

[@ifritzaima8009]

Wonderful jobb

[@MedicoVisual]

Thank you so much

[@user-sl4xw2mf8h]

Thankss I was so confused as in the book it was written that sec villi has a mesodermal core
I couldn't got it from which mesoderm? how?
You explained it amazingly sir

[@user-xl3cr4wi8p]

U are the father of Embryology

[@komalejaz2972]

👏👏👏👏

[@anwarsultana1776]

ورے گود Lecture

[@MedicoVisual]

Thanks

[@houriak848]

Hey, thx a lot for ur lecture just a note in langmans it's mentioned that anchoring villus extend from chorionic plate to maternal endometrium but in ur presentation it's just the top end can u pls clarify my confusion
Thx again for ur amazing work

[@MedicoVisual]

Langman is correct, Anchoring villi extend from Chorionic plate to Maternal Endodmetrium. This is in-line with what is being visualized in this lecture. Please watch 08:29 onward.

[@50rollnorahul96]

Thank you sir 😊😊
Eagerly waiting for formation of intra Embryonic mesoderm and cardiac embryology.🤠🤠

[@MedicoVisual]

You are most welcome. Intraembryonic mesoderm has been discussed in this video: ruclips.net/video/UdtXtanzXfw/видео.html.

[@50rollnorahul96]

@@MedicoVisual Ohh,I have written mesoderm instead of intraembryonic cavity😅😅 ,I have watched this video already .
BTW ,Thanks for reply sir .❤️❤️🤠🤠

[@MedicoVisual]

@@50rollnorahul96 You are most welcome and Thanks a lot for your support.

[@MIRCHANDANINIMISH]

Hi sir, Much gratitude from Kenya ... your embryology videos have helped me prepare for my mid-sem CATs next week ... thankyou so much.
Is there anyway we can access these videos as notes in PDF format ?

[@MedicoVisual]

Hello. I am sorry. I don't have PDF notes. However there are practice MCQs available with system-based embryology lectures. Those lectures are paid. Feel free to contact me if you cannot afford to pay full price. WhatsApp [phone] or email [e-mail]

[@noorrehman9104]

Sir,you did not upload lectures of gastrointestine

[@MedicoVisual]

Complete 3D Gastrointestinal System Embryology (including foregut and hindgut) is already available for a small fee at www.medicovisual.com/courses/premium-gastrointestinal-embryology-3d-masterclass
Do not hesitate to contact me if you have any questions or concerns.
WhatsApp: [phone]
Email: [e-mail]

[@theviolinos_]

Poor who don't know your channel

[@MedicoVisual]

Thank you so much. Spread the wealth by sharing the channel with others 😉

[@ROCKY-nr3ij]

Did not understood anything😐

[@MedicoVisual]

I am sorry. Did you not understand the accent or the content itself? If thats the accent, you can turn on CC for subtitles. If its the content, can you please specify what concept do you fail to understand? Actually some background knowldge is required to understand the specific details. I can explain it in a bit morr detail if you elaborate.