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BIO 150 FINAL EXAM Questions and
Answers (100% Correct Answers)
Already Graded A+
Difference between innate and Adaptive immunity
Ans: Innate immunity: defenses against any pathogen; rapid, present at
birth
Adaptive immunity: immunity or resistance to a specific pathogen;
© 2026 Assignment
slower to respond, has memory component
Physical components of host defense;
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Ans: Skin- Physical
Expert
Dermis: inner portion made of connective tissue
Epidermis: outer portion made of tightly packed epithelial cells
containing keratin, a protective protein
Shedding and dryness of skin inhibits microbial growth
Mucous membranes
Epithelial layer that lines the gastrointestinal, respiratory, and
genitourinary tracts
Mucus: viscous glycoproteins that trap microbes and prevent tracts from
drying out
Lacrimal apparatus: drains tears; washes eye
Ciliary escalator transports microbes trapped in mucus away from the
lungs
Earwax prevents microbes from entering the ear
, 2
Urine cleans the urethra via flow
Vaginal secretions move microorganisms out of the vaginal tract
Peristalsis, defecation, vomiting, diarrhea
Granulocyte cells;
Ans: Granulocytes are leukocytes with granules in their cytoplasm that
are visible with a light microscope
Neutrophils: phagocytic; work in early stages of infection
© 2026 Assignment
Basophils: release histamine; work in allergic responses
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Eosinophils: phagocytic; toxic against parasites and helminths
WBC differential count
Ans: - neutrophils :50-70% of WBCs; most numerous
- eosinophils: 2-4% of WBCs
- basophils: 0.5-1% of WBCs; rarest
•
- lymphocytes: 25% or more of WBCs
- monocytes: 3-8% of WBCs; largest WBC
Phagocytic cells
Ans: Phago: from the Greek, meaning eat
Cyte: from the Greek, meaning cell
Fixed macrophages are residents in tissues and organs
, 3
Free (wandering) macrophages roam tissues and gather at sites of
infection
Phagocytosis
Ans: Chemotaxis
Chemical signals attract phagocytes to microorganisms
Adherence
Attachment of a phagocyte to the surface of the microorganism
© 2026 Assignment
Ingestion
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Expert
Opsonization: microorganism is coated with serum proteins, making
ingestion easier
Digestion
Microorganism is digested inside a phagolysosome
Marigination
Ans: Margination is the sticking of phagocytes to blood vessels in
response to cytokines at the site of inflammation
Cells involved in parasitic defense; allergic reactions
Ans: eosinophils
• 2-4% of WBCs
• most important role is to attack parasitic worms; also play role in
allergies & asthma
Complement proteins
Ans: • group of at least 20 plasma proteins that normally circulate in
blood in an inactive state
BIO 150 FINAL EXAM Questions and
Answers (100% Correct Answers)
Already Graded A+
Difference between innate and Adaptive immunity
Ans: Innate immunity: defenses against any pathogen; rapid, present at
birth
Adaptive immunity: immunity or resistance to a specific pathogen;
© 2026 Assignment
slower to respond, has memory component
Physical components of host defense;
Guru01 - Stuvia
Ans: Skin- Physical
Expert
Dermis: inner portion made of connective tissue
Epidermis: outer portion made of tightly packed epithelial cells
containing keratin, a protective protein
Shedding and dryness of skin inhibits microbial growth
Mucous membranes
Epithelial layer that lines the gastrointestinal, respiratory, and
genitourinary tracts
Mucus: viscous glycoproteins that trap microbes and prevent tracts from
drying out
Lacrimal apparatus: drains tears; washes eye
Ciliary escalator transports microbes trapped in mucus away from the
lungs
Earwax prevents microbes from entering the ear
, 2
Urine cleans the urethra via flow
Vaginal secretions move microorganisms out of the vaginal tract
Peristalsis, defecation, vomiting, diarrhea
Granulocyte cells;
Ans: Granulocytes are leukocytes with granules in their cytoplasm that
are visible with a light microscope
Neutrophils: phagocytic; work in early stages of infection
© 2026 Assignment
Basophils: release histamine; work in allergic responses
Guru01 - Stuvia
Expert
Eosinophils: phagocytic; toxic against parasites and helminths
WBC differential count
Ans: - neutrophils :50-70% of WBCs; most numerous
- eosinophils: 2-4% of WBCs
- basophils: 0.5-1% of WBCs; rarest
•
- lymphocytes: 25% or more of WBCs
- monocytes: 3-8% of WBCs; largest WBC
Phagocytic cells
Ans: Phago: from the Greek, meaning eat
Cyte: from the Greek, meaning cell
Fixed macrophages are residents in tissues and organs
, 3
Free (wandering) macrophages roam tissues and gather at sites of
infection
Phagocytosis
Ans: Chemotaxis
Chemical signals attract phagocytes to microorganisms
Adherence
Attachment of a phagocyte to the surface of the microorganism
© 2026 Assignment
Ingestion
Guru01 - Stuvia
Expert
Opsonization: microorganism is coated with serum proteins, making
ingestion easier
Digestion
Microorganism is digested inside a phagolysosome
Marigination
Ans: Margination is the sticking of phagocytes to blood vessels in
response to cytokines at the site of inflammation
Cells involved in parasitic defense; allergic reactions
Ans: eosinophils
• 2-4% of WBCs
• most important role is to attack parasitic worms; also play role in
allergies & asthma
Complement proteins
Ans: • group of at least 20 plasma proteins that normally circulate in
blood in an inactive state
