A heart attack happens when blood flow to the heart suddenly. becomes blocked and the heart canât get oxygen. quickly, the heart muscle fails to pump and begins to die. disease (CHD), also called coronary artery disease.
The B-cell receptor is composed of two parts: i) A membrane-bound immunoglobulin molecule of one isotype (IgD, IgM, IgA or IgE).he B-cell receptor is composed of two parts: i) A membrane-bound immunoglobulin molecule of one isotype (IgD, IgM, IgA or IgE).
photoreceptors and chemoreceptors: They are modular in their architecture, and each module is associated with a different aspect of receptor function (110). A photoreceptor typically com-prises several discrete protein units known as modules or domains, each of which forms a co-valentlyconnected,compactlyfoldedportionof the sequence.