White blood cells in Blood
description
Transcript of White blood cells in Blood
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White blood cells often have irregularly shaped
nuclei.
65% of white blood cells are granular leucocytes as
they have granules in their cytoplasm. They are
formed in the bone marrow.
35% have no granules and are agranular. They are
formed in the lymph nodes, spleen, tonsils and
thymus.
White Blood Cells Blood
granular leukocytes agranular leukocytes
White Blood cells FeaturesPlace of
production
Lymphocytes •Contains large central nucleus
•Non-granular cytoplasm
•Produces antibodies
•Involves in tissue rejection and killing of tumor cells.
Lymph nodes
Lymph glands
Bone marrow
Phagocytes •Contains lobed nucleus.
•May be granular or non granular.
•Ingest foreign particles (e.g. bacteria) by phagocytosis
Bone Marrow
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Phagocytes are white blood cells with lobed nuclei.
They ingest solid particles such as germs, and digest them.
When the body is infected, phagocytes move to the site of
infection, and ingest and digest the germs.
Phagocytosis is a process by which the cell membrane
engulfs a food particle and brings it into the cell.
White Blood Cells Blood
pseudopodium
bacteria
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Lymphocytes are white blood cells with a single nucleus
which is roughly spherical in shape.
They secrete globulins known as antibodies.
Each antibody is specific.
When antibodies remain in the body, the body is said to be
immune to a specific disease.
The body would have developed natural active immunity if
the microbes enter the body through natural means.
When a person has been vaccinated, the immunity is
artificial active immunity.
White Blood Cells Blood
Pathogens in blood Toxins in blood
Lymphocytes
Antibodies Antitoxins
Agglutinate
bacteria
Destroy
bacteria
Attach to virus
Attaching to bacteria
& causing its
membrane to rupture
Clumping of
bacteria for more
efficient
phagocytosis
So that it
cannot bind to
host cell
Neutralise toxins
in blood
produce
stimulate
produceproduce
Act on Act on
Functions of antibodies
• Clumping of bacteria
• Attachment to protein
coat of virus
▫ Prevents virus from
being transported
▫ Prevents virus from
attaching to a host for
replication
Immunity
Antibodies remain in blood long after disease has been overcome
To prevent the patient from suffering the same disease again
Immunizations
Inject small amount of dead/inactivated bacteria
Stimulate lymphocytes to produce antibodies against bacteria
Inject dead bacteria into animals to induce formation of antibodies in them. Antibodies are then injected into humans
Organ transplant
If donor tissue/organ comes from same person
Tissue will not be rejected as cells have the same antigens
from the same donor.
Tissue rejection may occur when tissue comes from
another donor
Cells may be treated as foreign body and donor’s
lymphocytes may produce antibodies
Preventing tissue rejection
1. Matching of donor and recipient tissue
Tissues must be as genetically close as possible
Eg: Relatives should have more similar genes
2. Use immunosuppressive drugs to inhibit recipient’s immune system
Disadvantages:
Lower resistance to many other infections
Has to take drugs for the rest of his life
A white blood cell being attacked by the HIV virus.
Immune system being destroyed by the virus.