Nerve cells communicate by sending an electrical signal through an axon, from this molecules get released into the synapse this then binds itself onto receptor sites. With ion-linked channel receptors, the ligands get binded to a protein. The ion channels are then opened and the proccess gets repeated. Does that help?
In the picture attached to this question, the two diagrams above did not show very well but I believe that the first diagram contain four dots, which means that the correct option is A.
Carbon has six electrons, that is why 6 is its atomic number is 6 . In writing electronic configuration, two electrons are usually placed in the most inner shell while the other shells will have 8 electrons each. In the case of carbon which has 6 electrons, only four will remain after 2 electron has been put in its inner shell. Therefore the number of electron in its outermost shell will be four.
I would say D because mechanical weathering is the breaking up of rocks by physical forces
Scientists are preserving the DNA for research.
