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B cells

B cells    are immune cells that function primarily by producing antibodies. An antibody    is any of the group of proteins that binds specifically to pathogen-associated molecules known as antigens. An antigen    is a chemical structure on the surface of a pathogen that binds to T or B lymphocyte antigen receptors. Once activated by binding to antigen, B cells differentiate into cells that secrete a soluble form of their surface antibodies. These activated B cells are known as plasma cells.

T cells

The T cell    , on the other hand, does not secrete antibody but performs a variety of functions in the adaptive immune response. Different T cell types have the ability to either secrete soluble factors that communicate with other cells of the adaptive immune response or destroy cells infected with intracellular pathogens. The roles of T and B lymphocytes in the adaptive immune response will be discussed further in this chapter.

Plasma cells

Another type of lymphocyte of importance is the plasma cell. A plasma cell    is a B cell that has differentiated in response to antigen binding, and has thereby gained the ability to secrete soluble antibodies. These cells differ in morphology from standard B and T cells in that they contain a large amount of cytoplasm packed with the protein-synthesizing machinery known as rough endoplasmic reticulum.

Natural killer cells

A fourth important lymphocyte is the natural killer cell, a participant in the innate immune response. A natural killer cell (NK)    is a circulating blood cell that contains cytotoxic (cell-killing) granules in its extensive cytoplasm. It shares this mechanism with the cytotoxic T cells of the adaptive immune response. NK cells are among the body’s first lines of defense against viruses and certain types of cancer.

Lymphocytes
Type of lymphocyte Primary function
B lymphocyte Generates diverse antibodies
T lymphocyte Secretes chemical messengers
Plasma cell Secretes antibodies
NK cell Destroys virally infected cells

Visit this website to learn about the many different cell types in the immune system and their very specialized jobs. What is the role of the dendritic cell in an HIV infection?

Primary lymphoid organs and lymphocyte development

Understanding the differentiation and development of B and T cells is critical to the understanding of the adaptive immune response. It is through this process that the body (ideally) learns to destroy only pathogens and leaves the body’s own cells relatively intact. The primary lymphoid organs are the bone marrow and thymus gland. The lymphoid organs are where lymphocytes mature, proliferate, and are selected, which enables them to attack pathogens without harming the cells of the body.

Bone marrow

In the embryo, blood cells are made in the yolk sac. As development proceeds, this function is taken over by the spleen, lymph nodes, and liver. Later, the bone marrow takes over most hematopoietic functions, although the final stages of the differentiation of some cells may take place in other organs. The red bone marrow    is a loose collection of cells where hematopoiesis occurs, and the yellow bone marrow is a site of energy storage, which consists largely of fat cells ( [link] ). The B cell undergoes nearly all of its development in the red bone marrow, whereas the immature T cell, called a thymocyte    , leaves the bone marrow and matures largely in the thymus gland.

Questions & Answers

What is the most important organ in the human body?
Gbemi Reply
the heart
Phodiso
or brain
Phodiso
Why?
Gbemi
heart
Kelly
the brain specifically is referred to as the control centre ..all nerve impulses are send to the brain which stimulates other specific parts of the body
Phodiso
structure of a serous membrane
Ziyanda Reply
are you asking?
Isa
yes
MOHD
In anatomy, serous membrane (or serosa) is a smooth tissue membrane consisting of two layers of mesothelium, which secrete serous fluid. The inner layer that covers organs (viscera) in body cavities is called the visceral membrane. A second layer of epithelial cells of the serous membrane, called th
Isa
The two layers of serous membranes are named parietal and visceral. Between the two layers is a thin fluid filled space.[2] The fluid is produced by the serous membranes and stays between the two layers to reduce friction between the walls of the cavities and the internal organs when they move with
Isa
a continuation from the 1st one:: A second layer of epithelial cells of the serous membrane, called the parietal layer, lines the body wall. Between the two layers is a potential space, mostly empty except for a few milliliters of lubricating serous fluid that is secreted by the two serous membranes
Isa
Lubricated secretion of skin is called sebum
Jazil
haematopoietic
oyewale
what is the greater tronchanter?
Phodiso
Name the two phases of metabolism
Grace Reply
reproduction and growth
Zozo
how about anabolism and catabolism?
Japhar
In Simply Anabolism means formation... Catabolism means breakdown
Jazil
two phases of reproductio?
Japhar
Anabolism indicates potential & catabolism potential converts to kinetic
Doctor
Name the most important life process in the human body in terms of anatomy and physiology
Grace
Nervous system
Nimco
Every system is important for body functions
Jazil
what is the difference between the functions of the adhesion belt and the desmosomes?
Mason Reply
what are the derivatives of the germ layer?
Miriam Reply
zygote
Zozo
Pls explain the atlas of the cervical vertebral column
Ifunanya Reply
why does the material not allow in mri
Simran Reply
what do you mean 'mri'
Nimco
short for magnetic resonance imaging. "the researchers used MRI to record the brain activity" a medical examination performed using magnetic resonance imaging. "he's having an MRI to determine the extent of the injury" an image obtained by magnetic resonance imaging. "after looking at the MRI, the d
Riyaz
what is the meaning of sutures
Ibrahim Reply
i do not know
Nimo
immovable joints btn two bones.eg the skull bones
Japhar
Really,it's true
Nimco
Sutures are immovable junction between two bones e.g those of the skull
Surphy
what should I do to get or to know what to do for me to be excellent in the course of anatomy and physiology
Sandra Reply
study harder
Japhar
Between the heart and the Brain which one is more important to human being... discuss
Faith Reply
well the brain is important for motor skills, the heart is important for involuntary muscle movement supporting body functions. the body can survive without brain involvement, but the body cannot last without the heart
john
granted the heart is important, but the brain gives the body purpose
john
the brain is more important
Kevin
why?
john
brain
tracey
Even though the brain helps the human being to behave normally and purposefully, I think the heart is much more important cos human being cannot live without the heart
Dzifa
why?
john
change the question
Bind
hello guys
Kevin
heart
Kevin
it is difficult to select which organ is more important, now you can replace the heart with a mechanical device and the body could still function, and with technology today brain activity can also be replicated. But life would not be the same
john
there's coordination btn the two..so without any of them no life
Japhar
the heart
The brain is important to humans.
Zozo
what is homeostasis
Rebecca Reply
It is the condition when body feel comfortable
Jazil
Wo feels hungry, thirty due to homeostasis
Jazil
Is the maintenance of the internal environment of all the body cells for normal growth
Komolika
what is the composition of saliva
Vijay Reply
ഫസ്റ്റ് ചാപ്റ്റർ ഇംപോർട്ടൻസ് പോസ്റ്റ്
Reshma Reply
Yes....
Loving
nhi samjh aya
Anshika
Nhi wt is this
Loving
I don't know
Anshika
Okk wre frm u r
Loving
what is mean of? reshma
Asad
I don't know but would like to
Rebecca
D bone in d ankle joint re what ?
Ifunanya Reply
patellar
Ibrahim
I thought that patella us the bone found in the knee cap
Ifunanya
fib and tib join with tarsal form ankle joint
Ava
Thanks
Ifunanya
can one define a cell as a basic unit of a living organism
Michael Reply
cell is the structural and functional unit of living organisms
Fidel

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Source:  OpenStax, Anatomy & Physiology. OpenStax CNX. Feb 04, 2016 Download for free at http://legacy.cnx.org/content/col11496/1.8
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