Microbiology 290 FINAL EXAM Questions And Correct Answers | Latest 2026/2027 | GRADED A+ | 100% PASS - WCU

Microbiology 290 FINAL EXAM Questions And Correct Answers | Latest 2026/2027 | GRADED A+ | 100% PASS - WCU. where do b cells develop and mature? b cells develop in the bone marrow and mature there before entering the bloodstream and lymphoid tissues what is the main function of b cells? to recognize specific antigens and produce antibodies to neutralize or mark pathogens for destruction how do b cells recognize antigens? b cells have b cell receptors (bcrs) on their surface that bind directly to antigens plasma cells activated b cells that produce and secrete large amounts of antibodies specific to an antigen where do plasma cells come from? develop from b lymphocytes after activation by antigen binding and helper t cell signals main function of plasma cells to produce antibodies that target and neutralize pathogens or mark them for destruction what is the difference between plasma cells and memory b cells? 2 | P a g e plasma cells secrete antibodies immediately, while memory b cells remain dormant and respond quickly upon re-exposure to the same antigen structure of prokaryotes - no nucleus - no membrane bound organelles - unicellular - DNA in nucleoid structures of eukaryotes - nucleus with nuclear membrane - membrane bound organelles (mitochondria, ER, golgi) - uni or multicellular gram-positive cell walls - THICK layer of peptidoglycan - PURPLE or BLUE stain - teichoic and lipoteichoic acids present - no outer membrane - sensitive to penicillin/lysozyme - produce exotoxins gram-negative cell walls - THIN layer of peptidoglycan 3 | P a g e - PINK or RED stain - may be impediment to treatment of disease - outer membrane contains lipopolysaccharides - produce endotoxins and exotoxins similarities of prokaryotes and eukaryotes - have DNA - ribosomes present - have cell membrane, cytoplasm gram positive bacteria staphylococcus, streptococcus, bacillus gram negative bacteria e. coli, salmonella, neisseria general structure of viruses - contain dna or rna - surrounded by protein coat (capsid) - acellular 4 | P a g e - can only reproduce inside host cells recombinant DNA technology technology that combines genes from different sources into a single DNA molecule - uses restriction enzymes - used for gene cloning and making insulin PCR (polymerase chain reaction) used to copy and amplify minute quantities of DNA - used for DNA testing, cloning, disease detection, and forensic analysis antisepsis reduction in the number of microorganisms and viruses, particularly potential pathogens, on living tissue examples: iodine, alcohol -cide, -cidal suffixes indicating destruction of a type of microbe example: bactericide, fungicide, germicide, virucide degerming removal of microbes by mechanical means examples: handwashing, alcohol swabbing at site of injection 5 | P a g e disinfection destruction of most microorganisms and viruses on nonliving tissue example: phenolics, alcohols, aldehydes, soaps pasteurization use of heat to destroy pathogens and reduce the number of spoilage microorganisms in food and beverages example: pasteurized milk and fruit juices sanitization removal of pathogens from objects to meet public health standards examples: washing tableware in scalding water in restaurants -stasis, -static suffixes indicating inhibition, but not complete destruction, of a type of microbe example: bacteriostatic, fungistatic, virustatic aseptic refers to an environment or procedure free of pathogenic contaminants examples: handwashing, flame sterilization of lab equipment, prep of surgical field