00:01
All right, so problem one in our book asks us about paracrine signaling and the ligands produced.
00:09
Where are they coming from? so going down our list of answers, a, made by the cell.
00:16
Now, this is another type of signaling called autocrine signaling.
00:22
And something that helps me remember is auto, like autonomy.
00:27
So that is where the receptors are either, they're normally inside the cell and the cell is producing the ligands to make itself.
00:37
That's not paracrine signaling.
00:39
So a can't be our right answer.
00:42
B says that paracrine signaling ligands come from neighboring cells.
00:46
And a good example of this would be neurotransmitters.
00:50
Now over here you have your sending cell, your sending cell, and then over here, you have your receiving cell with the receptors.
01:00
And what the sending cell does is it releases its ligands into the surrounding areas.
01:11
And these cells, they are close to each other, but they are not touching.
01:15
There's this space in between them.
01:17
And these ligands are picked up by these receptors that then trigger an intercellular response, say, among an enzyme...