Chapter 11- Immunity

Question 1

List all the external defense/first line of defense of the immunity system

Answer 1

Skin
Tears
Mucus
Stomach acid
Genital fluid
Cilia
Goblet cells
Saliva

Question 2

Describe the appearance of a neutrophil

Answer 2

Has lobed nucleus
It is the most abundant (60%) white blood cell
Size: 12 micrometer - 15 micrometer
Its cytoplasm contains granules(vesicles that contains enzymes and bacteriacides)

Question 3

Describe the apperance of a lymphocyte

Answer 3

It is smaller in size compare to neutrophils

The nucleus takes up mist of the cell

Question 4

Describe the appearance of a monocyte and a macrophage

Answer 4

It is similar in size to a neutrophil(12 - 15 micrometer)
The nucleus is large, though as not as large as a lymphocyte’s
A monocyte leaves the blood stream when there is an infection and heads to the infection/inflammation site and matures into a macrophage

Question 5

List all the external defense/first line of defense of the immunity system

Answer 5

Skin
Tears
Mucus
Stomach acid
Genital fluid
Cilia
Goblet cells
Saliva

Question 6

What is cytokines?

Answer 6

Chemicals released by the B lymphocytes upon detecting an infection to promote the activity of other parts in the immune system

Question 7

Describe the appearance of a neutrophil

Answer 7

Has lobed nucleus
It is the most abundant (60%) white blood cell
Size: 12 micrometer - 15 micrometer
Its cytoplasm contains granules(vesicles that contains enzymes and bacteriacides)

Question 7

Describe the apperance of a lymphocyte

Answer 7

It is smaller in size compare to neutrophils

The nucleus takes up mist of the cell

Question 7

What is histamine?

Answer 7

A nitrogen based chemical that is produced by cells that are under attack by pathogen/toxin to increase the activity of certain parts of the immunity system

Question 8

Describe the appearance of a monocyte and a macrophage

Answer 8

It is similar in size to a neutrophil(12 - 15 micrometer)
The nucleus is large, though as not as large as a lymphocyte’s
A monocyte leaves the blood stream when there is an infection and heads to the infection/inflammation site and matures into a macrophage

Question 9

What is immunity?

Answer 9

The ability of an organism to resist a particular infection or toxin by the action of specific antibodies or sensitized white blood cells

Question 10

Types of immunity with example(s)

Answer 10

1. Active natural- normal infection
2. Active artificial- vaccine
3. Passive natural- mother’s breastmilk to foetus
4. Passive artificial- anti venom, anti toxin

Question 11

How does a secondary response works?

Answer 11

Upon primary infection, memory cells that are complementary to the specific pathogen are produced and circulates the blood. This provides immunological memory

Upon secondary infection, the response is faster as there is already an abundant number of memory B cells, memory killer T cells and memory T helper cells

These cells destroys the recognised pathogen from the primary infection faster compared to the primary response, and they are usually destroyed before they have established and able to do the body any harm

Question 12

How does a vaccine provides immunity?

Answer 12

A vaccine is a preparation of dead/weakened pathogens that is used to initiate a primary response of the immune system to provide immunological memory

Upon secondary infection, the secondary response is faster, thus there is barely any symptoms of infection as the pathogen is destroyed at a faster rate

Question 13

What is autoimmune?

Answer 13

A condition where the body stops recognizing the self cells and starts recognizing them as non self cells causing the immune system to start attacking the body

Question 14

Explain how myasthenia gravis is an example of autoimmune disease

Answer 14

Myasthenia gravis is an autoimmune disease that cause the decay of muscle due to inactivity. Symptoms include muscle weakening and drooping eyelids. This disease prevents nerve impulses from passing from nerves to skeletal muscles across a synapse

Upon a normal synapse, a chemical named acetylcholine is relased to transmit the message by hinding to the receptor. For a myasthenia gravis sufferer, T helper lymphocytes causes the production of antibodies that binds to the receptors of the skeletal muscle cell, preventing the binding of acetylcholine to the receptors. This causes the message to not be transmitted and the muscle remains inactive

Question 15

What is an antibody?

Answer 15

It is a large soluble Y shaped glycoprotein that floats around in the blood

Roles:

• Bind to pathogens to prevent them from entering cells
• Causes agglutinationof pathogens to ease phagocytosis
• Binds to pathogens and acts as flags to ease detection
• Bind to flagellum to minimise bacteria locomotion
• Bind to bacteria and causes lysis(bursting of the membrane of the cell)
• Combine with toxins to reduce/remove the effects(antitoxins)

Antibodies are found free floating(produced by plasma cells) or on the membranes of B lymphocytes

Question 16

Why can’t antibodies be made artificially?

Answer 16

They have to be made by biological process and the complex folding of antibody can only be done by the Golgi apparatus inside cells

Question 18

What is monoclonal antibodies and how are they produced?

Answer 18

Monoclonal antibodies are also knows as Mabs

The process of production of Mabs begins with creating an immune response in an animal(small mouse, rabbits) that results in the production of specific plasma cells

The plasma cells are then harvested from the spleen, where they ar found in high concentrations

The plasma cells are then fused with cancerous cell(uncontrollable mitosis) through a process called CELL FUSION

A large number of the cells don’t work, while some works and start producing antibodies and they are able to divide by mitosis(hybridoma)

The antibodies are then oroduced on a huge scale for indefinite periods