The correct option is B
Acetylcholine released into the junction between a motor neuron and a skeletal muscle binds to a sodium/potassium channel and opens it. This is an example of the ligand-gated channel.
The acetylcholine receptors are cation-selective members of the ligand-gated ion channels which are pentameric and also are oligomeric protein assemblies that process to convert a chemical signal through the postsynaptic membrane into an ion flux.
Acetylcholine opens the sodium and potassium channels of a cell which makes the concentrations of these two ions inside and outside stabilize and depolarize the membrane of the cell.
This depolarization will result in the formation of nerve impulses. The receptors in muscle fibers recognize acetylcholine as a sign of muscle contraction from neuron to muscle.
Therefore, acetylcholine receptors are actually pentameric ligand-gated ion channels but muscarinic acetylcholine receptors are coupled membrane proteins of seven helix G-proteins.
Learn to know more about the release of acetylcholine on
brainly.com/question/14202070
#SPJ4
<span>Steroids can cross the cell membrane because they are lipids and the membrane is lipid</span>
The answer is; D
A limiting factor is a resource in the environment that significantly affects the growth, distribution or abundance of an organism or population within an ecosystem. When this factor is controlled it can result in increased or decreased growth.
In this water, the level of the water table in the desert limits the growth of the cacti plants.
