<< Chapter < Page Chapter >> Page >

IgG    is a major antibody of late primary responses and the main antibody of secondary responses in the blood. This is because class switching occurs during primary responses. IgG is a monomeric antibody that clears pathogens from the blood and can activate complement proteins (although not as well as IgM), taking advantage of its antibacterial activities. Furthermore, this class of antibody is the one that crosses the placenta to protect the developing fetus from disease exits the blood to the interstitial fluid to fight extracellular pathogens.

IgA    exists in two forms, a four-chain monomer in the blood and an eight-chain structure, or dimer, in exocrine gland secretions of the mucous membranes, including mucus, saliva, and tears. Thus, dimeric IgA is the only antibody to leave the interior of the body to protect body surfaces. IgA is also of importance to newborns, because this antibody is present in mother’s breast milk (colostrum), which serves to protect the infant from disease.

IgE    is usually associated with allergies and anaphylaxis. It is present in the lowest concentration in the blood, because its Fc region binds strongly to an IgE-specific Fc receptor on the surfaces of mast cells. IgE makes mast cell degranulation very specific, such that if a person is allergic to peanuts, there will be peanut-specific IgE bound to his or her mast cells. In this person, eating peanuts will cause the mast cells to degranulate, sometimes causing severe allergic reactions, including anaphylaxis, a severe, systemic allergic response that can cause death.

Clonal selection of b cells

Clonal selection and expansion work much the same way in B cells as in T cells. Only B cells with appropriate antigen specificity are selected for and expanded ( [link] ). Eventually, the plasma cells secrete antibodies with antigenic specificity identical to those that were on the surfaces of the selected B cells. Notice in the figure that both plasma cells and memory B cells are generated simultaneously.

Clonal selection of b cells

This flow chart shows how the clonal selection of B cells takes place. The left panel shows the primary response and the right panel shows the secondary response.
During a primary B cell immune response, both antibody-secreting plasma cells and memory B cells are produced. These memory cells lead to the differentiation of more plasma cells and memory B cells during secondary responses.

Primary versus secondary b cell responses

Primary and secondary responses as they relate to T cells were discussed earlier. This section will look at these responses with B cells and antibody production. Because antibodies are easily obtained from blood samples, they are easy to follow and graph ( [link] ). As you will see from the figure, the primary response to an antigen (representing a pathogen) is delayed by several days. This is the time it takes for the B cell clones to expand and differentiate into plasma cells. The level of antibody produced is low, but it is sufficient for immune protection. The second time a person encounters the same antigen, there is no time delay, and the amount of antibody made is much higher. Thus, the secondary antibody response overwhelms the pathogens quickly and, in most situations, no symptoms are felt. When a different antigen is used, another primary response is made with its low antibody levels and time delay.

Questions & Answers

describe the urine formation
Sarah Reply
Body water
Kashif
the urine formation is described as the wrist fluid that comes out of body
Hellen
glomerular filtration, reabsorption, secretion.
Maria
nice
Hussain
good Hellen kehn
Dr
is it wast fluids or wrist?
Baldwin
how many bones does human have?
Akech
Good
Opeyemi
206
Emmi
about the urine formation Baldwin asked that is it wast fluid or wrist that comes out from the body
Frimpong
waste fluids.. Tubular Reabsorption: Glucose, Amino acids, Proteins, Vitamins, Lactate, Urea, Uric acid, NA+, K+, Ca2+, Mg2+, Cl-, HCO3-, H20 Tubular Secretions: Urea, Uric acids, Creatinine, H+, NH4+, K+ Each different section of the Nephron has a different mineral that absorbs or secrets
Emmi
thank you Emmi
Baldwin
No problem, Happy to help.. I have a photo of exactly which area does what but I don't think I can attach on this platform..
Emmi
***socratic.org/questions/how-is-urine-produced-in-the-kidneys On this web page if you stroll down, there is a picture describing it. its my favorite diagram. Very clear and informative
Emmi
what is single cell
Jimmy Reply
A unicellular organism, also known as a single-celled organism, is an organism that consists of a single cell, unlike a multicellular organism that consists of multiple cells. ... Many eukaryotes are multicellular, but many are unicellular such as protozoa, unicellular algae, and unicellular fungi.
Noor
Why is important to check if the blood if compatible before transfusion ?
Kelvin Reply
to avoid cases of intravenous clupping in blood which can be fatal....bcos blood is incopartable
John
Thank you.good answer
Kelvin
what are the clinical significant of thyroid gland
Jennifer Reply
what is a metabolism?
Kheth Reply
Metabolism is the sum total of all the chemical processes in the body. It is divided into an anabolic(building up) and catabolic(breaking down) metabolism)
Jonas
Oh ok
King
sir what is constructive and destructive metabolism
Soul
is anyone
Soul
Describe the system s that maintain the internal environment of a human body
Nora Reply
an organism is a living being that had a cellular structure and that can independently perform all physiological functions needed for life.
Nwecho Reply
a tissue is a group of similar cells that work together to perform a particular function
Nwecho
chemical level, cellular level, tissue level, organs level, organ systems, organisms
Nwecho Reply
they're reproduction but also produces hormones dus they're endocrine system
Nwecho
cells are smallest independent functional unit of a living organism
Nwecho
an organ is an anatomically distinct structure of the body composed of two or more tissue
Nwecho
an organ system is a group of organs that work together to perform a major function.
Nwecho
Structural Organization of the human body.
Tammy
What is a cavity
Isaac Reply
Permanently damaged areas in teeth that develop into tiny holes
MASLAH
what is meant by epithelial tissue
Zahid
What is the difference between regional anatomy and systematic anatomy?
Andrew Reply
Regional anatomy is the study of the interrelationships of all of the structures in a specific body region, such as the abdomen. ... In contrast, systemic anatomy is the study of the structures that make up a discrete body system—that is, a group of structures that work together to perform a unique
Tammy
Pls is that all
Petra
regional anatomy studies structures that contribute to specific body region example the thoracic region while systematic anatomy studies structures that contribute to specific body systems example respiratory system
Nwecho
so meaning of dissect
Mary Reply
it is the dismembering or the cutting of living organism to study the anatomical structure of it body
Kwasi
what are lymph nodes
Memory Reply
what is the best book that shows unit 1 about cell unit 2 about tissue unit 3 about embroyology
Abraham Reply
2
Hellen
to understand structure of body able to understand function of system. to understand how to build human body and function
Dereje Reply
hi
Neela
to determine body structures
Petra Reply
to know the use of each and every part of our body
Petra
to understand how our body structures work to support our lives
Petra
Is this a question?
Tammy
So what was the question?
Thamie
All the body work together to make the whole organism life possible
Kwasi
what is the importance of conversation
Hellen
To be able to identify the parts of the body and their functions
Hodasi
ok
Hodasi
Ideas are shared during conversation also informations are given
Hodasi
it reduces cost
Kwasi

Get Jobilize Job Search Mobile App in your pocket Now!

Get it on Google Play




Source:  OpenStax, Anatomy & Physiology. OpenStax CNX. Feb 04, 2016 Download for free at http://legacy.cnx.org/content/col11496/1.8
Google Play and the Google Play logo are trademarks of Google Inc.

Notification Switch

Would you like to follow the 'Anatomy & Physiology' conversation and receive update notifications?

Ask