WGU D115 OBJECTIVE ASSESSMENT (OA) EXAM COMPLETE UNIT 1-
UNIT 7 QUESTIONS AND CORRECT DETAILED ANSWERS WITH
RATIONALES (VERIFIED ANSWERS) |ALREADY GRADED A+ 2025
LATEST UPDATED
What are the 3 layers of human defense? What happens during each? - (ANSWER)Physical-
protect against damage and infection are composed of tightly associated epithelial cells including
those of the skin and of the membranous sheets lining the gastrointestinal, genitourinary, and
respiratory tracts. Mechanical- "washing" the surfaces (sloughing off of dead skin, vomiting,
urination, coughing). Biochemical barriers- secrets substances meant to trap of destroy
microorganisms. (Mucus, sweat, saliva, tears, sebaceous glands, and earwax).
What is the second line of defense and the process? - (ANSWER)Inflammatory response- rapid
and nonspecific, protective response to cellular injury from any cause. It can occur only in
vascularized tissue.
How do acute and chronic inflammation differ? - (ANSWER)Acute- Short duration, 8-10 days
from onset to healing. The three systemic changes associated with the acute inflammatory
response are fever, leukocytosis, and plasma protein synthesis. Chronic inflammation- can be a
continuation of acute inflammation that last 2 weeks or longer. It can also occur as a distinct
process without much preceding acute inflammation.
What are the phases of wound healing and the process that takes place during each? -
(ANSWER)Phase 1- Inflammation- includes coagulation and the infiltration of cells that
participate in wound healing, including platelets, neutrophils, and macrophages. Phase 2-
Proliferation and New Tissue Formation (Reconstruction)- wound begins to heal. This stage
begins 3-4 days after injury and continues for as long as 2 weeks. Phase 3- Remodeling and
Maturation- phase for recovering normal tissue structure that can persist for years
How does the inflammatory response differ in neonates? - (ANSWER)Neonates often have
transiently depressed inflammatory function, particularly neutrophil chemotaxis and alternative
complement activity.
, How and why does aging affect innate immunity? - (ANSWER)Aging alters the tissue
microenvironment and macrophage function with changes in wound healing neoangiogenesis
and fibrosis.
What is the third line of defense and the process that takes place? - (ANSWER)Adaptive
immunity (immune response or immunity)- the third line of defense in the human body. Consists
of lymphocytes and serum proteins called antibodies. - Secondary responder-augments the initial
defenses against infection and provides long term security against re-infection. - B cells- humeral
can kill free floating pathogens - T cells- cell - mediated- can kill pathogens hiding inside cells.
How and why does the neonate have a poorly developed immune response? - (ANSWER)The
human neonate has a poorly developed immune response, particularly in the production of IgG.
The fetus and neonate are protected in utero and during the first few post-natal months by
maternal antibody that was actively transported across the placenta.
What terms are collectively known as hypersensitivity reactions? - (ANSWER)Allergy,
autoimmunity, and alloimmunity are collectively known as hypersensitivity reactions.
Hypersensitivity Response I - IgE mediated- primary cause of common allergies. Binds with
mast cells which release histamine. (initiates allergic reaction). Histamine release leads to
bronchial smooth muscle contraction, bronchoconstriction, and immune response II- tissue
specific- wrong blood type administered or hemolytic disease of the newborn. Complement
pathway activated III- Immune complex mediated IV- cell mediated - graft rejection
What are some causes of autoimmune diseases? - (ANSWER)Autoimmune disease can be
caused by the exposure of a previously sequestered antigen, the development of a neoantigen, the
complications of infectious disease, the emergence of a forbidden clone of lymphocytes, or the
consequence of ineffective peripheral tolerance. The mechanisms for imitation of autoimmune
diseases may already be within humans.
What are some examples of alloimmune disorders? And why do these occur? -
(ANSWER)Alloimmunity is the immune systems reaction against antigens on the tissues of
other members of the same species. - Transient neonatal disease - Transplant rejection -
Transfusion reaction
UNIT 7 QUESTIONS AND CORRECT DETAILED ANSWERS WITH
RATIONALES (VERIFIED ANSWERS) |ALREADY GRADED A+ 2025
LATEST UPDATED
What are the 3 layers of human defense? What happens during each? - (ANSWER)Physical-
protect against damage and infection are composed of tightly associated epithelial cells including
those of the skin and of the membranous sheets lining the gastrointestinal, genitourinary, and
respiratory tracts. Mechanical- "washing" the surfaces (sloughing off of dead skin, vomiting,
urination, coughing). Biochemical barriers- secrets substances meant to trap of destroy
microorganisms. (Mucus, sweat, saliva, tears, sebaceous glands, and earwax).
What is the second line of defense and the process? - (ANSWER)Inflammatory response- rapid
and nonspecific, protective response to cellular injury from any cause. It can occur only in
vascularized tissue.
How do acute and chronic inflammation differ? - (ANSWER)Acute- Short duration, 8-10 days
from onset to healing. The three systemic changes associated with the acute inflammatory
response are fever, leukocytosis, and plasma protein synthesis. Chronic inflammation- can be a
continuation of acute inflammation that last 2 weeks or longer. It can also occur as a distinct
process without much preceding acute inflammation.
What are the phases of wound healing and the process that takes place during each? -
(ANSWER)Phase 1- Inflammation- includes coagulation and the infiltration of cells that
participate in wound healing, including platelets, neutrophils, and macrophages. Phase 2-
Proliferation and New Tissue Formation (Reconstruction)- wound begins to heal. This stage
begins 3-4 days after injury and continues for as long as 2 weeks. Phase 3- Remodeling and
Maturation- phase for recovering normal tissue structure that can persist for years
How does the inflammatory response differ in neonates? - (ANSWER)Neonates often have
transiently depressed inflammatory function, particularly neutrophil chemotaxis and alternative
complement activity.
, How and why does aging affect innate immunity? - (ANSWER)Aging alters the tissue
microenvironment and macrophage function with changes in wound healing neoangiogenesis
and fibrosis.
What is the third line of defense and the process that takes place? - (ANSWER)Adaptive
immunity (immune response or immunity)- the third line of defense in the human body. Consists
of lymphocytes and serum proteins called antibodies. - Secondary responder-augments the initial
defenses against infection and provides long term security against re-infection. - B cells- humeral
can kill free floating pathogens - T cells- cell - mediated- can kill pathogens hiding inside cells.
How and why does the neonate have a poorly developed immune response? - (ANSWER)The
human neonate has a poorly developed immune response, particularly in the production of IgG.
The fetus and neonate are protected in utero and during the first few post-natal months by
maternal antibody that was actively transported across the placenta.
What terms are collectively known as hypersensitivity reactions? - (ANSWER)Allergy,
autoimmunity, and alloimmunity are collectively known as hypersensitivity reactions.
Hypersensitivity Response I - IgE mediated- primary cause of common allergies. Binds with
mast cells which release histamine. (initiates allergic reaction). Histamine release leads to
bronchial smooth muscle contraction, bronchoconstriction, and immune response II- tissue
specific- wrong blood type administered or hemolytic disease of the newborn. Complement
pathway activated III- Immune complex mediated IV- cell mediated - graft rejection
What are some causes of autoimmune diseases? - (ANSWER)Autoimmune disease can be
caused by the exposure of a previously sequestered antigen, the development of a neoantigen, the
complications of infectious disease, the emergence of a forbidden clone of lymphocytes, or the
consequence of ineffective peripheral tolerance. The mechanisms for imitation of autoimmune
diseases may already be within humans.
What are some examples of alloimmune disorders? And why do these occur? -
(ANSWER)Alloimmunity is the immune systems reaction against antigens on the tissues of
other members of the same species. - Transient neonatal disease - Transplant rejection -
Transfusion reaction
