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Joined 1 year ago
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Cake day: June 12th, 2023

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  • It has a part that is embedded in a mitochondrial membrane and works as a rotor. The other part is sticking out from the membrane and is responsible for synthesis of ATP from ADP and phosphate. An off-axis part of the rotor pushes the stator, it changes shape and pushes ADP and phosphate together, until they fuse to ATP.

    To make the rotor move, it makes use of membrane potential. One side of the membrane has a lot more H⁺ (just protons, really) than the other. The excess H⁺ want to go to the other side. The membrane doesn’t let them through. It is hydrophobic on the inside, so it does’t let through anything charged (like H⁺) or polar (like water). This is the potential and it has quite a lot of energy. ATP synthase lets the H⁺ through by binding them to the rotor in the membrane in a particular place and releases them in another in such a way that forces the rotor to turn almost a full turn before they can leave and stops it from rotating the other way. As mentioned, the rotation is transfered to the stator, changing its shape and thus creating ATP. As a side note, multiple H⁺ are bound on the rotor along its circumference, so each rotation is powered by the potential energy of multiple protons.

    Of course, it’s a bit more complicated than that, but I don’t think there’s anything downright wrong or misleading in what I wrote. I hope I managed to make it understandable. Also, I recommend animations of the synthase on youtube.



  • That’s the case for most species.

    As a very specific and highly functional example of critical viral proteins in other organisms, there wouldn’t be any placental mammals without viruses. https://en.m.wikipedia.org/wiki/Placenta

    Mammalian placentas probably first evolved about 150 million to 200 million years ago. The protein syncytin, found in the outer barrier of the placenta (the syncytiotrophoblast) between mother and fetus, has a certain RNA signature in its genome that has led to the hypothesis that it originated from an ancient retrovirus: essentially a virus that helped pave the transition from egg-laying to live-birth.






  • lemming@sh.itjust.workstoData is Beautiful@lemmy.worldHeight reported by men
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    1 month ago

    I honestly don’t know how tall I am. I know I’m taller than last time I was seriously measured, but I don’t know by how much and I don’t care. But everyone shrinks during the day anyway. Measuring height to precise centimeters has just a little more sense than weighing someone with precision of ⅒ of kilogram. I have basically no chance but to estimate and possibly round.



  • There are colour scales that combine colours and intensities consistently, so that if you discard (or can’t percieve) colour information, you still get a nice black to white scale. For a moment, I though the map used cviridis scale, which has this property and is designed to look as similar as possible to people with various variants of colour blindness. But then I realised that the scale used here has the brightest point in the middle, not on one side.