Animal defence part 1

Flashcards covering concepts related to immunology and the immune system.

Pathogen

Any single microorganism that can cause an issue within our body, often causing a disease.

Immune System Phases

Recognition (discriminating self from non-self), Activation (mobilizing immune cells), and Effector (cells fight against the pathogen).

Innate Immunity (Non-Specific Defense)

Quick, not specific, recognizes pathogen, and sends information to adaptive immunity.

Adaptive Immunity (Specific Defense)

Highly specific, takes longer to activate, produces antibodies, and has long-lasting memory.

Lymphoid Tissues

Tissues involved in the production of immune cells; examples include thymus, bone marrow, spleen, and lymph nodes.

Lymphatic System

A parallel system to the bloodstream where white blood cells circulate and mature; mostly contains lymphocytes.

Multipotent Hematopoietic Stem Cells

Located in the bone marrow, these cells generate both red and white blood cells.

Myeloid Progenitor Cells

Differentiate into red blood cells, platelets, and certain white blood cells (leukocytes).

Leukocytes

White blood cells and composed of phagocytes and lymphocytes.

Phagocytes

Cells able to engulf and digest pathogens or fragments.

Lymphocytes

Smaller cells that do not perform phagocytosis; include B lymphocytes, T lymphocytes, and natural killer cells.

Granulocytes

Cells containing granules in their cytoplasm, derived from myeloid progenitor cells.

B Lymphocytes

Produce antibodies.

Antigen

Information extracted from the pathogen and presented to immune system cells.

Major Histocompatibility Complex (MHC)

Complexes on cell surfaces that present antigens to immune cells; MHC I on all nucleated cells, MHC II mostly on immune cells.

T Cells

Lymphocytes with receptors that interact with antigens presented by MHC complexes.

Cytokines

Signaling molecules that promote recruitment and activation of immune cells.

Complement System

A system activated along with innate immunity to create pores on pathogens, causing lysis.

Interferons

Signaling molecules that make cells more resistant to specific pathogens.

Natural Killer Cells

Recognize and destroy virus-infected and tumor cells as part of the innate immunity.

Inflammation Process

Indication that the immune system is reacting to a pathogen, involving recruitment of immune cells through released substances.

Prostaglandins

Molecules that weaken blood vessel membranes, allowing immune cells to move into tissues.

Histamine

Molecule involved in itching and allergic reactions during inflammation.

Fever

Increased body temperature that enhances lymphocyte and phagocytosis production while creating an unfavorable environment for pathogens.

Sepsis

Uncontrolled inflammation spreading through the bloodstream.

Toll-like Receptors

Receptors on leukocytes (e.g., macrophages) that recognize specific molecules on pathogens.

NFKB Transcriptional Factor

Activates specific genes involved in the macrophage response.

Passive Immunity

Receiving antibodies from another source.

Tolerance

Discriminating between self and non-self; lymphocytes are screened to avoid reacting to self-antigens.

Humoral Immune Response

Involves B cells and the production of antibodies.

Cellular Immune Response

Involves cytotoxic T cells.

T Helper Lymphocytes

Instruct B cells to produce antibodies and stimulate cytotoxic T cells.

T Cell Receptor

Structure on T lymphocytes able to recognize antigens.

Clonal Selection

Eliminating B lymphocytes that recognize self-antigens.

Active Immunity

Developing a specific immune response through memory cells, providing long-lasting protection.

Vaccination

Instructing the immune system to produce antibodies by using inactive or weakened pathogens.