Probably ink or lead. I don't see a picture.
Hi :)
For middle school biology, I think all you need to know is that when you see the word organic it instantly means it has the element: carbon.
And usually a lot of hydrogens too, but never without carbon.
I uploaded a picture of an organic molecule called capsaicin.
It's what makes hot peppers spicy!
Notice how many C you see for Carbon!
Hope this helps :)
Adenosine regulates synaptic activity through its actions on presynaptic autoreceptors. Adenosine A1 receptors are expressed at a presynaptic locus withinside the BLA and that activation those receptors substantially inhibits glutamate launch possibility onto BLA pyramidal neurons.
The adenosine A2A receptor is a G-protein-coupled receptor that may be a most important goal of caffeine and vital for regulating myocardial oxygen consumption, coronary blood flow, and CNS neurotransmitters, hence a receptor of hobby for brand new drug development.
The adenosine A2A receptor is particularly gift with inside the brain, heart, lungs, and spleen. The adenosine A2B receptor has its most important distribution with inside the big gut and bladder, and the adenosine A3 receptor is gift inside the lungs, liver, brain, testis, and heart.
To learn more about G-protein-coupled receptor here
brainly.com/question/28296117
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