Lymphatic system/B cells/T cells

Where are all lymphocytes produced?

In the bone marrow

Where do B cells develop?

In the bone marrow

Where do T cells mature?

In the thymus

What are the two main types of lymphocyte?

B cells and T cells

What is the first stage of the primary immune response, after a B cell first encounters a pathogen?

Its receptors bind to a complementary antigen on the surface of the pathogen

What is the second stage of the primary immune response, after a B cell’s receptors have bound to the antigen?

B cell internalises the pathogen and processes its antigens

What is the third stage of the primary immune response, after the B cell has processed the anitgens?

B cell presents processed antigens on its surface

What is the fourth stage of the primary immune response, after B cell has presented antigens on its surface?

Helper T cell’s receptors bind to complementary anitgens on B cell’s surface

What is the fifth stage of the primary immune response, after T cell has bound to antigens on B cell’s surface?

Helper T cell releases chemicals to stimulate the B cell to clone itself

What is the sixth stage of the primary immune response, after B cell has cloned itself?

Clones differentiate into plasma cells or memory B cells

What type of molecule are antibodies?

Proteins

How many polypeptide chains does an antibody have?

4

What region are the 4 polypeptide chains known as in an antibody?

The constant region

How many heavy and light chains are there in an antibody?

2 heavy chains and 2 light chains

What are the polypeptide chains in an antibody held together by?

Disulphide bridges

What region are the antigen-binding sites in an antibody known as?

Variable regions

How many antigen-binding sites does an antibody have?

2

How many antigens can an antibody bind to at a time?

2

Which cells secrete antibodies?

Plasma cells

How long typically does a plasma cell survive for in the body?

A few days

Give an example of how an antibody can destroy a pathogen.

Agglutination

What is agglutination?

The process of clumping pathogens together using antibodies

Why is agglutination useful?

• Becomes harder for pathogen to spread around the body

• Makes it easier for phagocytes to locate and destroy them

How long can a memory B cell survive for in the body?

Years

What do memory B cells do after the pathogen is gone, following the primary immune response?

Remain in the body

Which immune response do B memory cells carry out when the same pathogen re-invades the body?

The secondary immune response (same as primary immune response, with a few differences)

What are the two key differences between the primary and secondary immune response?

• Secondary immune response is quicker

• Secondary immune response produces more plasma cells

What is a potential consequence of the secondary immune response being quicker?

You may not experience symptoms, as the non-self cell is wiped out before it can make a visible impact

What is a consequence of the secondary immune response producing more plasma cells?

A greater concentration of antibodies in the body

What is antigenic variability?

The ability for antigens to mutate and vary in shape

What are the primary and secondary immune responses collectively known as?

The humoral response

What can T cells bind to?

Can only bind to antigens on antigen-presenting cells

Which three cell types can act as antigen-presenting cells?

Phagocytes, B cells, virus-infected body cells

How does a cell become an antigen-presenting cell?

First processes the antigens, then presents them on its surface

What 2 types of T cell can T cells in the thymus develop into?

Cytotoxic T cells and helper T cells

What does naive mean in terms of B cells and T cells?

It hasn’t encountered an antigen before

What is the helper T cell stimulated to do when it binds to an antigen on an APC?

Clone itself

What 3 things can cloned helper T cells stimulate?

Phagocytosis, B cells to clone, cytotoxic T cells

How do cloned helper T cells stimulate phagocytosis?

They release chemicals that attract phagocytes to a pathogen

What do cytotoxic T cells kill?

Virus-infected body cells

What does a cytotoxic T cell do once it has bound to an antigen on a virus-infected body cell?

Releases perforin

What does perforin do?

Causes holes to form in the virus-infected body cell’s cell membrane. This disrupts the cell’s balance, as it allows substances to uncontrollably enter and leave.

What is the response involving T cells known as?

The cell-mediated response

Lymphatic fluid

straw colored fluid that goes between capillary blood and tissues

Lymphatic fluid

transport excess tissue fluid back into the circulatory system

Tonsils

masses of lymphatic tissue that produce lymphocytes

Spleen

sac-like mass of lymphatic tissue located in the left abdominal cavity, just below the diaphragm

Thymus

lymphatic and endocrine gland most active during the neonatal and pre-adolescent periods that produces lymphocytes

Immunity

the body’s ability to resist disease

Autoimmune

when the body’s immune system mistakenly attacks normal tissue

against

contra

lymph

lympho

breakdown, dissolve

lysis

false

pseudo

thymus

thymo

tissue

histo

gland

adeno

producing or causing

gen

disease

patho

spleen

spleno

Histamine

________ is a naturally occurring substance released by the immune system?

expand

Histamines make tiny blood vessels______?

antibodies

Proteins produced in blood tissue to help destroy foreign bodies are known as?

the immune system

________ provides protection against potentially damaging substances that invade the body?

Anaphylactic shock

After being stung by another wasp, Phoebe experiences _______?

Histamine

_______ made phoebe’s blood vessels contract and airways open up during her allergic reaction?

antibodies

Unlike T cells, B cells produce ________ to kill off the virus?

macrophages

The body’s immune system has its own clean-up crew called ______ to dispose of the cell’s debris?

the circulatory system

The system working with the lymphatic system to remove waste and excess fluid from the tissue is the ______?

transports

Lymph fluid ________ oxygen and carbon dioxide to the cells?

getting a vaccine

Artificial acquired immunity comes from where?

4 weeks - 12 years

What is the incubation period for AIDS?

armpit

Axillary lymph nodes are located in the ______?

spleen

What organ is a part of the lymphatic system?

thoracic duct

The largest lymphatic vessel is called the ______?

hodgkin’s disease

A form of cancer of the lymph nodes, what disease is usually characterized by painless swelling of the lymph nodes?

infected mononucleosis

What lymphatic system disease is caused by a virus, is spread by oral contact, and occurs most frequently in young adults and children?

blood in capillaries, the tissues

Lymph acts as an intermediary between the ______ and ________, and carries digested food, oxygen and hormones to the individual cells?

interstitial fluid

Fluid that filters out of capillaries into the microscopic spaces between tissue cells is called?

immunity

The body’s ability to resist pathogens & foreign materials and the diseases they cause is called?