Immunology 1 Flashcards
(20 cards)
The immune system is composed of:
Organs/cells/molecules
This is an organised system of organs, cells and molecules that interact together to defend the body against disease.
Immune system
An example of these are viruses, bacteria, fungi, and Protozoa. These are everywhere in life and some may also be pathogens (disease causing)
Microbes
This deals with the production of white blood cells (leukocytes)
Primary lymphoid organs
These are the sites in which immune responses are initiated (the general site)
Secondary lymphoid organs
This is a primary lymphoid organ. It is a source of stem cells that develop into cells of the innate and adaptive immune responses
Bone marrow
This is a primary lymphoid organ. It is known as the “school” of white blood cells known as T cells. This develops the T cells to learn not to react to self, but also to develop their receptors into ones that detect infection.
Thymus
This is a secondary lymphoid organ. It is the site of initiation for immune responses against blood borne pathogens.
Spleen
This is a secondary lymphoid organ. It is located along the lymphatic vessels and functions to filter lymph fluid and blood from tissue. It is also a site of immune responses.
Lymph nodes
Ps. When activated lymph nodes expand.
What are the immune system’s 3 layers of defence?
Physical + chemical barriers, innate arm and adaptive arm
What are examples of physical barriers in the body?
The skin and mucous membranes
This is a layer of the skin that contains dead cells, keratin and phagocytic immune cells
Epidermis
This is a thick layer of connective tissue (in the skin) , collagen and blood vessels and phagocytic immune cells underneath the epidermis.
Dermis
What are the immune cells in the skin?
Dendritic cells
These are tightly packed live cells in the mucous membranes - constantly renewed, mucus producing goblet cells
Epithelium
These line parts of the body that lead to the outside and are exposed to air
Mucosal membranes
This is the mechanism that allows mucus to move up to the pharynx through cilia.
Mucociliary escalator
What are the 2 arms of the immune system?
Innate arm and defensive arm
The innate defences are composed of what?
Surface barriers and internal defences.
- These are usually fixed to detect molecular components shared by many pathogens.
- has no specific memory
The adaptive defences are composed of what?
B cells and T cells
- Adaptive immunity improves during response
- it is slow and highly specific
- has a memory and thus is able to develop an immune response for pathogens it has previously identified
