Remaining Embryology Slides

You may have noticed when you were watching the embryology lecture that the video ended after the discussion of slide 47. There was actually another 5 minutes of lecture, but the recording system shut down early that day. There are actually just a couple things that you need to remember from those last few slides – and I’ll list those for you below – but first, here’s a short video explaining those last few slides.

Short video

Here is the embryology lecture video covering those remaining slides. The part to watch starts at 1:50:30 and ends at 1:55:45. I wish I could just post the actual 5 minute clip for you, rather than the whole 2 hour video – but I can’t edit this video yet.

Take-away points

Slide 48 (above) explains what happens to the pharyngeal grooves (most just disappear) and pouches (some of them give rise to important structures). For this slide, just remember the origins of the thymus (3rd pouch) and parathyroids (superior = 4th and 5th pouches, inferior = 3rd pouch).

Slide 49 (above) shows what can happen if the grooves don’t close properly during embryogenesis: you can get cysts (which are enclosed under the skin), or sinuses (which have an open end on the skin surface). This slide just shows you an example of how this stuff is actually clinically relevant – so for this slide, you don’t need to memorize anything!

Slides 50-53 just review what we covered, and show you when we’ll be covering the rest of embryology. Nothing to memorize from these slides!

Questions about stains and embryology

I already got an email with questions! I’m so happy – I love it when you guys ask questions. I’ll often post them here (without names of course), because if one person has a question, it’s likely that there are lots of students wondering the same thing. Here are the questions, along with my answers.

Q. For tissue specimens stained with hematoxylin and eosin, would you recommend students to become thoroughly familiar with what cell parts/organelles are negatively/positively charged? If so, do you have any resources you would recommend? Continue reading