1) The skin is the human body’s first defense against infection. Continuos with the skin are the…

1) The skin is the human body’s first defense against infection. Continuos with the skin are the…
1) The skin is the human body's first defense against infection. Continuos with the skin are the epithelia lining the respiratory, gastrointestinal and urogenital tracts. The skin and musocal surfaces provide well-maintained barriers that prevent most pathogens entering the host tissues. Which of the following represent chemical anti-microbial barriers 1. Mucus production 2. Flow of fluid such as tears 3. Microbiome or normal flora 4.Lysozyme in tears and nasal secretions 5.Defensins 6. Acidity in urogenital tract A) 1,2 B) 3 C) 3,6 D) 4,5,6 E) all 1-6 2) Which of the following pairs is mismatched? A) monocyte: macrophage B) Plasma cell: common myeloid precursor granulocyte macrophage progenitor: neutrophil D) megakaryocyte/erythroid progenitor: red blood cell E) Common lymphoid precursor: natural killer cell 3) The membrane-bound proteins on human cells that dissociate and inactivate alternative C3 convertase to avoid complement activation are: A) factor B and factor H B) factor H and factor C) decay-accelerating factor and membrane cofactor protein. D) decay-accelerating factor and factor H E) properdin and MCP 4) Which of the following statements is true about human immunoglobulin classes: 1. IgE is the most common immunoglobulin for allergies involving mast cells sensitization ii. IgG and IgM are best at activating complement iii. IgM is smaller than IgG and therefore IgM is more readily able to access antigens in extracellular spaces of da and infected tissues iv. IgG is the main antibody in mucosal surfaces and in other secretions including milk, saliva, sweat and tears A) i, ii and iii B) all are true C) i and ii, D) ili and iv   Apr 11 2022 08:26 PM