ATI RN
Immune System Questions Questions
Question 1 of 5
What is the role of CD40L in T cell activation?
Correct Answer: A
Rationale: CD40L (on Th cells) prolongs DC survival ; binding , proliferation , and TCR activation are indirect or separate.
Question 2 of 5
Which lymphatic area is larger in a child than an adult?
Correct Answer: C
Rationale: The thymus is larger in children, shrinking with age; spleen , nodes , and duct don't vary as significantly.
Question 3 of 5
Antibodies, complement proteins, and phagocytic cells provide effective protection against all of the following types of infections in Figure Q2.1, except:
Correct Answer: C
Rationale: Assuming Q2.1 lists infection types, intracellular pathogens (e.g., viruses) resist antibodies/complement/phagocytosis ; extracellular pathogens are cleared.
Question 4 of 5
Early studies analyzing the antibody protein fragments generated after proteolytic cleavage revealed important information about the overall structure of the antibody molecule. Which cleavage pattern (indicated by the red triangles in Figure Q4.5) yields a fragment that has the same antigen-binding avidity as the intact antibody, but is unable to activate complement after binding to a pathogen?
Correct Answer: B
Rationale: Assuming Q4.5 shows cleavages, Fab retains binding but lacks Fc for complement; exact pattern inferred.
Question 5 of 5
Vertebrate eyes are Single-lens eyes with
Correct Answer: D
Rationale: Vertebrate eyes have a single lens where light is focused by the cornea and lens, the lens shape adjusts for near and far vision, and photoreceptors in the retina detect light. All options are correct.