Alleles are forms of the same gene with small differences in their sequence of DNA bases. These small differences contribute to each personâs unique physical features. Genes are made up of DNA.Each chromosome contains many genes. A gene is the basic physical and functional unit of heredity. Genes, which are made up of DNA, act as instructions to make molecules called proteins. In humans, genes vary in size from a few hundred DNA bases to more than 2 million bases.lleles are forms of the same gene with small differences in their sequence of DNA bases. These small differences contribute to each personâs unique physical features. Genes are made up of DNA.
To make a muscle contract, the acetylcholine produced in the presynaptic neuron of the neuromuscular junction must bind to the nicotinic receptors on the postsynaptic side. Each of these receptors consists of 5 subunits that form a pentagonal structure around a central channel.
Best Answer: Many nerves in the human body secrete acetylcholine at their nerve endings. The acetylcholine diffuses accross a gap called a synapse and stimulates the next nerve or a muscle. This action of acetylcholine has to be brief in order for the brain to be able to change it orders to the rest of the body. Therefore acetylcholinesterase causes water to be added to the acetylcholine molecule to break it down into choline and acetic acid.