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, What is the primary difference between innate and Innate immunity is rapid, present at birth, and provides nonspecific defenses;
adaptive immunity? adaptive immunity is slower to respond, specific to a pathogen, and includes a
memory component.
What is the definition of susceptibility in the context of Susceptibility is the lack of resistance to a disease.
immunology?
What is the function of Toll-like receptors (TLRs)? TLRs are receptors on host cells that bind to pathogen-associated molecular
patterns (PAMPs) to initiate an immune response.
What are pathogen-associated molecular patterns PAMPs are molecular structures found on pathogens, such as LPS, flagellin,
(PAMPs)? peptidoglycan, and viral DNA/RNA, that are recognized by host immune cells.
What is the result of TLRs binding to PAMPs? The host cell releases cytokines that regulate the intensity and duration of the
immune response.
What is the normal range for a white blood cell (WBC) 4,000 to 11,000 cells per microliter.
count in an adult?
What might a high WBC count indicate? Bacterial infections, autoimmune diseases, or side effects of medications.
What might a low WBC count indicate? Viral infections, pneumonia, autoimmune diseases, severe bacterial infections,
medication side effects, or cancers.
What are the two main layers of the skin and their roles The dermis (inner connective tissue) and the epidermis (outer epithelial layer
in immunity? containing keratin), which acts as a formidable physical barrier.
How does the skin inhibit microbial growth? Through the shedding of dead cells, dryness, and the presence of keratin.
What is the function of the lacrimal apparatus? It produces and drains tears to wash the surface of the eye.
What is the 'ciliary escalator'? A mechanism that transports microbes trapped in mucus away from the lungs.
What is the role of the epiglottis in immunity? It prevents microorganisms from entering the lower respiratory tract during
swallowing.
How do sebum and vaginal secretions contribute to They create an acidic environment (pH 3-5) that inhibits the growth of many
chemical defense? microbes.
What is the role of lysozyme in the innate immune It is an enzyme found in perspiration, tears, saliva, and urine that destroys
system? bacterial cell walls.
Why is the low pH of gastric juice (1.2-3.0) important? It destroys most ingested bacteria and toxins.