Anonymous said: I need your advice. This semester I had Histology for the first time, but I failed, and the next one I'll have Embryology with the same Professor, but I don't want to fail again, there's something basic that I should know about embryology?

hyacynthus:

i-heart-histo:

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Never have the immeasurably complex events of the first 4 weeks of human development been so succinctly and eloquently précised.

This is embryology anonymous!

No really. Think about it…these are the absolute basics of embryological development:

  • We start life as two cells united during the events of fertilization.
  • The cells fuse and proliferate to form a cluster.
  • The cluster reorganizes to form a flat, two-layered germ disc
  • This quickly transforms into a three layered disc during an event known as gastrulation.
  • The three layers are the famous germ layers: ectoderm (dorsal, sky blue), mesoderm (middle, red) and endoderm (ventral, yellow). The illustration shows these layers sandwiched between some extra-embryonic structures like the yolk sac (orange) and amniotic cavity (turquoise blue).

Fact: Babies are not flat discs. This three-layered disc must undergo some incredibly complex changes in order to become much more baby-like…right?

Double Fact: Babies are not actually that complex. They are just tubes surrounded by organs, muscles, skin and bones. Parents know only too well that they have a mouth at one end for putting food in and an anus at the other end for elimination of waste.

So the question is, how do you make a tube from a flat disc?

The answer is remarkably simple really. You just roll it up.

The less sticky way to make a baby…Take three different colored sheets of paper each representing a different layer of the germ disk. One blue (ectoderm, on top), one red (mesoderm, middle) and one yellow (endoderm, bottom). Now make a tube by rolling them. Congrats! You just made a baby!

Something similar happens to the germ disc. It undergoes lateral folding (the sides of the disc roll underneath itself; not shown here) and cranio-caudal folding (where the head and tail curl ventrally; shown here).

Just like your paper baby, this process essentially ensures that the outer layer of the tube is covered in ectoderm (blue) - this becomes the baby’s skin. The inside of the tube becomes the baby’s digestive tract from mouth to anus and is lined with endoderm (yellow). And, almost all of the baby in between is formed from mesoderm (red).

When baby gets older, goes out on its first date, and has that first kiss. He/she temporarily unites his/her endoderm lined digestive tract with the endoderm lined gut tube of their partner. Thus creating a continuous tube from the butthole of kisser A to kisser B.

Ironically, if more people thought about this statement while they were actually kissing, there would actually be much fewer babies in the world.

i-heart-histo x

To add on a little systematics bit, organisms for whom the first opening that forms is the anus are called deuterostomes, while in protostomes the first opening is the mouth.

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Reminder: Women do not need to be polite to someone who is making them uncomfortable.

(Source: hardqueersoftfemme, via madqueenjes)

sherlokidoki:

mafiagrape:

sixpenceee:

This girl and her chicken face swap 

This is the creepiest shit

I was gonna scroll passed this but I got a glimpse of her eyes and thought they looked weird and I scrolled back up and my heart literally stopped 

sherlokidoki:

mafiagrape:

sixpenceee:

This girl and her chicken face swap 

This is the creepiest shit

I was gonna scroll passed this but I got a glimpse of her eyes and thought they looked weird and I scrolled back up and my heart literally stopped 

(via dangerhamster)

sassykardashian:

sailingonsuccess:

sassykardashian:

Science side of tumblr how do I become a jellyfish

Jellyfish have no brains. You’re already pretty close.

Okay WOW

(via ktsaurusr3x)

validx2:


Crucial curve  

validx2:

Crucial curve  

(via thezookeeperslife)

(Source: vh1, via thezookeeperslife)

earthlynation:

Las Gralarias Glassfrog (Nymphargus lasgralarias) (by Lucas M. Bustamante-Enríquez)

earthlynation:

Las Gralarias Glassfrog (Nymphargus lasgralarias) (by Lucas M. Bustamante-Enríquez)

(via thezookeeperslife)

sonira:

calliedope:

I DO NOT KNOW HOW TO REMOVE MY ROLLER SKATES EVERYTHING IS VERY FAST AND I AM VERY AFRAID

(Source: mareepe, via greatashpectations)

jaclcfrost:

do u ever have a thought that’s so fuckin inappropriate that u feel like dumping a bucket of water on urself like. calm down, self. tone it down. think about jesus

(via dangerhamster)

one-superwholock-to-rule-em-all:

audreyii-fic:

Wherein Ten continues to bullshit his way through being a Time Lord

*blames himself to get himself out of trouble*

(Source: how-ood, via local-whovian)