Antibodies, antigens, antigen-antibody reactions, cells and tissues of lymphoreticular and hematopoietic systems, and individual and collective components of cell-mediated and humoral immune response.
Biology 2e is designed to cover the scope and sequence requirements of a typical two-semester biology course for science majors. The text provides comprehensive coverage of foundational research and core biology concepts through an evolutionary lens. Biology includes rich features that engage students in scientific inquiry, highlight careers in the biological sciences, and offer everyday applications. The book also includes various types of practice and homework questions that help students understand—and apply—key concepts. The 2nd edition has been revised to incorporate clearer, more current, and more dynamic explanations, while maintaining the same organization as the first edition. Art and illustrations have been substantially improved, and the textbook features additional assessments and related resources.
By the end of this section, you will be able to do the following:
Explain cross-reactivity
Describe the structure and function of antibodies
Discuss antibody production
View the animation to see how one type of immune cell-the helper T cell-interprets a message presented at the surface of the cell membrane. The message is an antigen, a protein fragment taken from an invading microbe. A series of events unfolds that results in the production of many clones of the helper T cell. These identical T cells can serve as a brigade forming an essential communication network to activate B cells, which make antibodies that will specifically attack the activating antigen.
Fundamentals of Biology focuses on the basic principles of biochemistry, molecular biology, genetics, and recombinant DNA. These principles are necessary to understanding the basic mechanisms of life and anchor the biological knowledge that is required to understand many of the challenges in everyday life, from human health and disease to loss of biodiversity and environmental quality.
This course is an advanced undergraduate seminar based upon discussions and critical analysis of primary literature in the field of immunology. Every infection consists of a battle between the invading pathogen and the resisting host. To be successful, a pathogen must escape the many defenses of the host immune system until it can replicate and spread to another host. A pathogen must prevent one of three stages of immune function: detection, activation, or effector function. Examples of disease specific immune evasion and the mechanisms used by pathogens to prevail over their host's immune systems are discussed. What these host-pathogen interactions reveal about the normal function of the immune system and about basic cell biological processes, such as protein maturation and degradation, are also considered.
IgA is present at low concentrations in plasma, and has minimal function inside the body. However, it is specially adapted for action at mucosal surfaces and as such, is present in high concentrations in mucosal secretions and in colostrum (and milk). In many species (dogs, cats and pigs), it is the major antibody in
IgD is present in ruminants, pigs, dogs and rodents but has not been identified in horses, cats, rabbits and chickens. It is mainly expressed on the surface of B-cells i.e. it is never secreted.
Unlike IgM, IgG and IgA, IgE does not function as a soluble antibody, with binding to Fc? receptors required before it can bind to the target antigen, and is found in low levels in blood plasma. Like IgA, it is produced by plasma cells and is mainly localised to mucosal surfaces.
IgG is the major antibody in blood plasma, and constitutes at least 80% of all antibodies in the body. It is the smallest immunoglobulin, so can readily leave the blood plasma and enter tissues. They can also cross the placenta, providing adaptive immunity to the foetus when the mother is under attack. IgG is also present in breast milk.
IgM is the primordial antibody and, although a monomer, is secreted as a pentamer (five monomers joined by disulphide bonds with two monomers joined by a J chain). This gives it ten identical antigen binding sites although IgM usually has relatively low affinity for its antigen. Its heavy chain is type mu (ľ).
Also called antibodies, Immunoglobulins (Ig) are the soluble form of B cell receptors (BCR) released by plasma cells after they have been activated. Immunoglobulins have to bind to a number of different antigens in a variety of environments and as such there are several different immunoglobulin classes. Each class has an optimum environment of action.
This sequence explores the elements of innate and acquired immune defense mecahnisms, the cells involved, their development and maturation, and biomolecular cellular communication mechanisms required to successfully fight off infection.
