Students asked "Why do we cry when we get hurt? I couldn't find a definitive answer, but here are a couple that sounded plausible: | Here's the video I told you about that talks about how different people deal with pain in different ways: |
Ty wants to know "Why can I feel something when two atoms can't touch?"
This is an interesting question. The following answer from Mousse_is_Optional on Reddit is one that I think is most understandable:
You can take two permanent magnets, and use one to push the other across a table without ever actually touching one to the other. Same with atoms. The atoms of your hand and the atoms of the wall don't physically touch each other, but they're pushing on each other all the same. Your nerves "feel" this electromagnetic push, and your brain interprets it as touch because that's what makes the most sense on the macroscopic level. Source
This is an interesting question. The following answer from Mousse_is_Optional on Reddit is one that I think is most understandable:
You can take two permanent magnets, and use one to push the other across a table without ever actually touching one to the other. Same with atoms. The atoms of your hand and the atoms of the wall don't physically touch each other, but they're pushing on each other all the same. Your nerves "feel" this electromagnetic push, and your brain interprets it as touch because that's what makes the most sense on the macroscopic level. Source
Students in class wanted to know "Why do we get goose bumps and shiver when we're cold" | Students in class also wanted to know "Why do we get goose bumps when we're cold and scared?" |
Someone asked "I know there are pain receptors. What stimulus triggers pain?"
The following stimulates the sensory nerve cells called nociceptors (source):
The following stimulates the sensory nerve cells called nociceptors (source):
- Intense chemical (e.g., chili powder in the eyes)
- mechanical (e.g., cutting, crushing)
- thermal (heat and cold)
This lead me to wonder "If a knife cuts your finger, what is stimulating your pain receptors once the knife is gone (after the cut has been made)?" Here is the answer from klenow on Reddit (source):
Cell damage is one of the big ones.
When a cell pops open, it releases stuff (e.g., endothelin, bradykinins) that shouldn't be outside of the cell. This stuff hangs around and causes pain.
Another factor is the arachidonic acid pathways. In response to damage, cells will start to convert membrane lipids into things eicosanoids. These are a class of molecules that do a lot of things to regulate the injury response. One of these things is cause pain (they also help stop blood loss and recruit inflammatory cells to the area). The "function" of the pain is to let you know you are injured and keep you from messing with it (and thereby worsening the injury).
As an aside, it's these pathways that are partially blocked by NSAIDs like aspirin and ibuprofen.
Cell damage is one of the big ones.
When a cell pops open, it releases stuff (e.g., endothelin, bradykinins) that shouldn't be outside of the cell. This stuff hangs around and causes pain.
Another factor is the arachidonic acid pathways. In response to damage, cells will start to convert membrane lipids into things eicosanoids. These are a class of molecules that do a lot of things to regulate the injury response. One of these things is cause pain (they also help stop blood loss and recruit inflammatory cells to the area). The "function" of the pain is to let you know you are injured and keep you from messing with it (and thereby worsening the injury).
As an aside, it's these pathways that are partially blocked by NSAIDs like aspirin and ibuprofen.
Here's a video we didn't get to watch. It shows how understanding how the human body works enables us to design things like prosthetic arms. This video shows how they are able to create a prosthetic arm that a person can control with their thoughts. The next step is to design touch receptors that send signals back. | |