Show newer

🧫 The synaptic terminal has these entities here, which are called synaptic vesicles, and they're small, little organelles.

🧫 They're little vesicles made of a membrane; just like the cell has a cell membrane, these vesicles have a vesicular membrane.
The neurotransmitters are within the vesicular membrane.

🧫 And, the neurotransmitter can be any number of a number of different molecules — , , , , , , , , , .

🧫 The neurotransmitters are packaged in vesicles. The second thing that's important about this is that we can use the synthesis of a as a therapeutic tool.

🧫 So, for instance, Dopamine is missing in .
It's not that dopamine isn't made per say, that's there's a problem with making it — it's that the cells that make it die.

🧫 There's something called 'Mass Effect', which means that you take the starting chemical (the substrate) and then through a series of enzymatic processes reaction, through a series of enzymatic reactions, we end up with a neurotransmitter.

🧫 In the case of Dopamine, what we do to treat in most people with Parkinson's is that we give them the substrate — and so that (drug) is what is commonly known as or .

🧫 So we flood the system with substrate, and the goal is to get a little bit of that neurotransmitter out of the system.

Image source: in.pinterest.com/pin/119627552

Show thread

Machine learning illuminates material's hidden order
phys.org/news/2020-03-machine-
Extreme temperature can do strange things to metals. In severe heat, iron ceases to be magnetic. In devastating cold, lead becomes a superconductor.

⚡ Neurons sit at a resting membrane potential of about -65 mV.

⚡ Small little potential differences — which are on the order of less than one millivolt up to, say, five millivolts — can travel along the neuron.

⚡ They might travel, but they're going to peter out pretty quickly. So, it's not going to work to simply rely on these small potential changes if we have to go long distances.

⚡ The longest neuron that we possess is a cell that has a cell body right at the base of the spine. And it sends one process all the way down to the toe, and it sends another process all the way up to the medulla.

⚡ Because neurons are so long, we use something called the Action Potential. And the Action Potential goes really far up and comes back down in height. So, it's about 100 mV.

⚡ So from the resting memory potential (-65mV) to the top of the Action Potential — which happens at around, say, 20mVs or so — we're talking about roughly 100 millivolts of difference. And that can get communicated all the way up. That's not going to get lost.

⚡ And what carries that Action Potential is: —
We looked at potassium being in very high concentration in a cell and much lower outside a cell. The reverse is true for sodium.
And so, the sodium comes flooding in, and because it's positively charged, that's what takes the cell up to this very high membrane potential.

⚡ Now the ability for a neuron to communicate using an Action Potential is a slow process unless we add one more thing, and that is an insulator —essentially a very nice insulator —called myelin.

Show thread

⚡ Electrical language of cells ⚡

⚛️ In a living organism, we don't use electrons. Instead, we use molecules that have a charge, and those molecules are called ions.

⚛️ So these ions are present within the context of cells. And all cells have what are called cellular membranes, which are made up mostly of fat. It's important to understand that most of a membrane is fat. And this is like a layer of oil surrounded by a couple layers of water.

⚛️ Let's consider an ion that's positively charged, and let's consider one to be potassium ion (K+).

⚛️ This potassium ion is very happy in water, but it can't get through oil. It's not gonna pass through there. So it's gonna bounce off this membrane. And the only way for it to get through is via a special place which we're gonna call an ion channel.

⚛️ The physical force for this potassium ion is to leave the cell because of lower concentration of ions outside the cell than in the cell (osmosis).
But, on the other hand, the cell is actually negatively charged. And outside the cell is grounded.

⚛️ The potassium ion is positive and so there's an electrical force that attracts it into the cell.

⚛️ The potential at which the physical (osmotic) force and the electrical force will be equal is where the membrane is gonna sit.

⚛️ And we have to worry about three ions -- the potassium ion, the sodium ion, which is also positively charged, and chloride ion. And once we take into consideration each of these ions, what we see is that this cell is going to sit at rest at about -70 to -60 millivolts (with respect to the potential outside the cell).

Show thread

🔸 Motor neurons are a very special type of neuron. If they die, you can no longer move muscles.

🔸 The motor neurons are contained either in the brain stem or in the spinal cord. But, there are no motor neurons in the forebrain.

🔸 So the motor neurons in the brain stem move the face, move the mouth, move the larynx, and are responsible for speech and swallowing, facial expressions, things like that.

🔸 The motor neurons in the spinal cord are responsible for movements of all the arms, our legs, our trunk. All of our movement that we do with our body happens through the spinal cord.

Show thread

@design_RG In 's Maharashtra, they are already using depolymerized plastic as fuel.
Watch: youtu.be/c_bNmiDYn5g

eSagan 🇮🇳  
🌱 #EcoIndia: Could a fuel generated from #plasticwaste replace #fossilfuels and meet energy needs? :india: https://youtu.be/c_bNmiDYn5g IF YOU HAV...

@nothingplanet Thank you for asking me. I just read the discussion and I don't think I can contribute anything more; you have provided enough rational arguments. Moreover, biology is really not the area of my expertise. Maybe @arteteco can help.

I forgot to add the source to the original image. Here it is: reddit.com/r/IncredibleIndia/c

eSagan 🇮🇳  
:india: Meghalaya, #India Just in case you're not aware of: Meghalayan Age, named after #Meghalaya, is the latest age or uppermost stage of the Qua...
Show thread

Rainmaker1973Climate (@Rainmaker1973c@twitter.com) Tweeted:
In the search to find an environmentally friendly alternative for fossil fuels, scientists from the developed a new technique for safely & efficiently producing 25 times more hydrogen fuel by using a specific type of rust and light source t.co/oKgzo0VyhP t.co/ALBFXt6SSZ twitter.com/Rainmaker1973c/sta

Magazine (@AstronomyMag@twitter.com) Tweeted:
70,000 years ago, a nomadic star came within a light-year of the Sun, shaking up our solar system. t.co/WYdHYljkHH twitter.com/AstronomyMag/statu

Big Think (@bigthink@twitter.com) Tweeted:
90,000-year-old human hybrid found in ancient cave. Her parents were two different human species. t.co/tegPYkPVdo t.co/DCFlSVC0W3 twitter.com/bigthink/status/12

Show older
Qoto Mastodon

QOTO: Question Others to Teach Ourselves
An inclusive, Academic Freedom, instance
All cultures welcome.
Hate speech and harassment strictly forbidden.