Inheritance Patterns, Immunology, and Microglia

Vocabulary flashcards covering inheritance patterns, immune system components, immune disorders, and the roles of microglia in health and disease.

Autosomal Dominant Inheritance

Pattern in which an affected individual appears in every generation and must have at least one affected parent; males and females are affected equally.

Autosomal Recessive Inheritance

Trait often skips generations; affected individuals can be born to two unaffected carrier parents, and males and females are affected equally.

X-Linked Recessive Inheritance

Mostly affects males, is passed from a carrier mother to her sons, and shows no father-to-son transmission.

X-Linked Dominant Inheritance

Affects both sexes but often more females; all daughters (and no sons) of an affected male are affected.

Mitochondrial Inheritance

Trait transmitted only through the mother; all children of an affected mother inherit it, whereas affected fathers do not pass it on.

Pedigree Symbols

Standard shapes used in pedigrees: circle = female, square = male, filled = affected, slashed = deceased, etc.

Vertical Transmission

Appearance of a genetic trait in successive generations, characteristic of dominant inheritance.

Innate Immunity

Immediate, nonspecific defense with no memory; includes physical barriers and cells such as phagocytes, NK cells, mast cells, eosinophils, and basophils.

Adaptive Immunity

Slower, antigen-specific response that generates memory; involves B cells and T cells and improves after vaccination.

Phagocytes

Innate immune cells (e.g., neutrophils and macrophages) that engulf and destroy pathogens.

Neutrophils

Fast-acting phagocytes in blood that serve as a first cellular defense against infection.

Macrophages

Large phagocytes that reside in tissues and ingest pathogens and debris; include microglia in the CNS.

Natural Killer (NK) Cells

Innate lymphocytes that recognize and kill virus-infected or cancerous cells without prior sensitization.

Mast Cells

Granular cells involved in inflammation and allergic reactions through release of histamine and other mediators.

Eosinophils

Granulocytes that combat parasitic infections and participate in allergic responses.

Basophils

Blood granulocytes that release histamine and help mediate allergic and inflammatory reactions.

Microglia

Resident macrophages of the brain and spinal cord that clear debris, defend against pathogens, and support development and plasticity.

Primary Immune Response

First exposure to an antigen; slow and produces low antibody levels while generating memory cells.

Secondary Immune Response

Subsequent antigen exposure; rapid and strong due to memory cells formed during the primary response.

Autoimmune Disorder

Condition in which the immune system mistakenly attacks self-tissues (e.g., lupus, type I diabetes).

Immunodeficiency

Impaired or absent immune function, leading to increased susceptibility to infection (e.g., HIV/AIDS).

Hypersensitivity

Excessive or inappropriate immune reaction, such as allergies or anaphylaxis.

Alzheimer’s Disease (Microglia Role)

Chronic microglial activation releases pro-inflammatory cytokines and ROS, contributing to neuronal damage and cognitive decline.

Multiple Sclerosis (Microglia Role)

Autoimmune demyelinating disease in which microglia present antigens, release inflammatory signals, and degrade myelin.

Traumatic Brain Injury (Microglia Role)

After trauma, microglia clear debris but prolonged activation can cause excessive inflammation and secondary damage.

Parkinson’s Disease (Microglia Role)

Loss of dopaminergic neurons activates microglia, which release toxic substances that may worsen neurodegeneration.

Synaptic Pruning

Microglia-mediated elimination of excess synapses during development; dysregulation may contribute to neurodevelopmental disorders such as autism.