Exam 3 Flashcards
Overall Concepts of the associated chapters (100 cards)
What is innate immunity?
The ‘always-on’ first line of defense, fast but no memory.
Innate immunity acts quickly against pathogens without prior exposure.
What are the three layers of skin?
Epidermis, Dermis, Hypodermis.
Each layer has distinct roles in protecting against microbial invasion.
How do tight junctions contribute to physical defenses?
They seal off deeper tissues.
Tight junctions act like zippers to prevent pathogen entry.
What is the function of mucous membranes?
They trap pathogens and debris, aided by cilia.
Mucociliary escalator helps sweep debris upward.
What role does sebum play in chemical defenses?
It lowers skin pH, blocking microbes.
Sebum contains oleic acid which helps maintain skin barrier.
What is the complement cascade?
A series of serum proteins with four shared outcomes: Opsonization, Inflammation, Chemotaxis, Cytolysis.
It enhances the ability of antibodies and phagocytic cells to clear pathogens.
What are the main types of granulocytes?
Neutrophils, Eosinophils, Basophils.
Each type has a specific role in the immune response.
What is the primary function of neutrophils?
To act as the most abundant phagocyte and form pus.
They quickly respond to infections by engulfing pathogens.
What are PAMPs?
Pathogen-associated molecular patterns.
They bind to PRRs on phagocytes to initiate immune responses.
What induces fever?
Pyrogens reset the hypothalamus (PGE₂).
Fever helps slow microbial growth and speeds up repair processes.
What is meant by specificity in adaptive immunity?
Targets one antigen.
Specificity allows for precise immune responses against specific pathogens.
What are the major classes of antibodies?
IgG, IgA, IgM, IgD, IgE.
IgG is notable for crossing the placenta.
What is herd immunity?
Population-wide protection buffer.
It protects individuals who are not immune by reducing the spread of disease.
What is the difference between bacteriostatic and bactericidal drugs?
Bacteriostatic halts growth, bactericidal kills bacteria.
The choice depends on the patient’s condition and the severity of the infection.
Define zoonosis.
Animal-derived infection.
Reverse zoonosis is when diseases are transmitted from humans to animals.
What are virulence factors?
Substances that enhance the pathogenicity of an organism.
They include toxins and enzymes that help pathogens invade and damage host tissues.
What does ID₅₀ measure?
Infection dose for 50% to get sick.
It quantifies the infectiousness of a pathogen.
What is the definition of endotoxin?
Gram-negative LPS toxin.
Endotoxins are part of the outer membrane of Gram-negative bacteria and can trigger severe immune responses.
What is the role of macrophages in the immune system?
Big eaters and antigen-presenting cells (APCs).
They engulf pathogens and present antigens to T cells.
Fill in the blank: ______ is the term for the protective mechanism of cilia moving mucus upward.
Mucociliary escalator.
This mechanism is crucial for clearing pathogens from the respiratory tract.
What is the function of cilia in the mucociliary escalator?
Move mucus to throat for expulsion
The mucociliary escalator helps in trapping and expelling pathogens from the respiratory tract.
Define tight junction
Leak-proof cell seal
What is the role of complement in the immune response?
Serum proteins causing OICC outcomes
What is opsonization?
Tagging pathogens for eating
