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.
Acetylcholine receptors are located on the motor end plate or  postsynaptic sarcolemma. Otto Loewi was a German pharmacologist  whose discovery of acetylcholine earned the 1 â¦ 936 Nobel prize in  Physiology or Medicine which he shared with Sir Henry Dale.  Acetylcholine is a neurotransmitter.