BYU General Microbiology Chapter 8 – Dr. Robison – Flashcards
Unlock all answers in this set
Unlock answersquestion
| innate resistance |
answer
| resistance to pathogens due to physiological properties of humans |
question
| 1st line of defense |
answer
| nonspecific, stops things from coming in skin mucous membranes chemicals |
question
| 2nd line of defense |
answer
| non-specific, defends after they're in the body, most of it from blood, 5 ways: phagocytosis, extracellular killing be leukocytes, nonspecific chemical defenses, inflammation, fever |
question
| 3rd line of defense |
answer
| specific defense lymphocytes, antibodies |
question
| skin: physical components |
answer
| microbial hell (large intestine=microbial heaven) 2 layers: epidermis, dermis |
question
| epidermis |
answer
| tightly packed cells sheds 10 billion cells per day (removing microbes too) epidermal dendritic cells/ Langerhans cells: phagocytize pathogens |
question
| Dermis |
answer
| contains callogen- gives strength to resist abrasions which could introduce pathogens |
question
| Skin: chemical components of defense |
answer
| sweat and sebum |
question
| sweat |
answer
| salty -> hypertonic solution lysozyme -> cuts cross links in cell walls |
question
| sebum |
answer
| pliable- less likely to tear lower pH: inhibits most bacteria |
question
| mucus membranes |
answer
| 2 layers: epithelium connective layer that supports epithelium |
question
| epithelium |
answer
| living cells, tightly packed, continually shedding cells |
question
| microbial antagonism- 5 reasons that make it hard for pathogens to compete |
answer
| secrete antimicrobial substances consume all the nutrients change pH helps stimulate 2nd line of defense give vitamins to host |
question
| chemicals in 1st line |
answer
| lacrimal glands bathe eye saliva stomach acid |
question
| blood plasma components |
answer
| water, electrolytes, dissolved gasses, nutrients, proteins |
question
| serum |
answer
| part of plasma, only antibodies |
question
| formed elements definition and 3 types |
answer
| cells and cell fragments in blood erythrocytes platelets leukocytes |
question
| erythrocytes |
answer
| red blood cells, carry O2 and CO2 |
question
| Platelets |
answer
| involved in blood clotting and inflamation |
question
| leukocytes |
answer
| white blood cells- defend against invaders 2 types: granulocytes and agranulocytes remember: GRANny PHIL is A CYTE |
question
| Granulocytes |
answer
| 3 types: neutrophils eosinophils basophils |
question
| neutrophils |
answer
| 50-70% of WBCs > 10 billion made every day major phagocytes cells of acute inflamation |
question
| Eosinophils |
answer
| 1-3% of WBC parasite defense |
question
| Basophils |
answer
| .5-1% of WBC contain histamine |
question
| Agranulocytes |
answer
| 2 types Lymphocytes Monocytes |
question
| Lymphocytes |
answer
| 20-40% of WBC most involved in specific immunity |
question
| Monocytes |
answer
| 1-6% of WBC leave blood and mature into macrophages |
question
| macrophages |
answer
| phagocytes either fixed to tissue or wandering |
question
| fixed macrophages |
answer
| microglial cells (CNS) mesangial cells (kidney) kupffur cells (liver) |
question
| what could increased eosinophils indicate? |
answer
| allergies parasitic worm infection |
question
| what could increased leukocytes, mostly neutrophils indicate? |
answer
| bacterial diseases |
question
| what could increased lymphocytes indicate? |
answer
| viral infections |
question
| phagocytosis |
answer
| performed mostly by neutrophils and macrophages, have receptors for bacterial surface components and opsonins |
question
| extracellular killing by leukocytes |
answer
| eosinophils natural killer lymphocytes neutrophils |
question
| eosinophils |
answer
| mainly attack worms (helminths) by secreting substances that weaken or kill it |
question
| natural killer lymphocytes |
answer
| jason bourne- sees their weird and kills them secrete substances on the surface of virally infected cells and tumor cells |
question
| neutrophils |
answer
| leak antimicrobials and trapping webs (NETs) |
question
| Nonspecific chemical defenses |
answer
| lysozyme complement interferon defensins lactoferrin |
question
| complement system |
answer
| complements the action of antibodies when complement is activated -> lysis of foreign cell activated in 2 ways classic pathway alternate pathway |
question
| the classical pathway |
answer
| complements the action of antibodies 4 functions: induce inflammation opsonization chemotaxis of phagocytes lysis of foreign cells |
question
| The alternate (properdin) pathway |
answer
| less efficient than classical pathway useful before antibodies are made activation occurs independent of antibodies initiated by properdin B,D, P and bacterial/fungal LPS and endotoxins starts reactions that lead to classical pathway |
question
| Interferons |
answer
| proteins that inhibit the spread of viruses (esp. ones with RNA genomes) cause symptoms associated with viral infections 3 classes: alpha, beta, gamma |
question
| interferons present in early stages of infection |
answer
| alpha and beta |
question
| interferon that appear in later stages of infection |
answer
| Gamma |
question
| interferon therapy |
answer
| not very effective |
question
| Defensins |
answer
| small peptides ways it attacks pathogens: cationic- attracted to bacteria amphipathic- punch holes in cytoplasmic membranes interferes with internal signaling and metabolic processes prevents biofilms makes bacterial proteins vulnerable to heat |
question
| inflammation |
answer
| increases defensin production 2 types: acute Chronic 4 cardinal signs: redness heat swelling pain |
question
| acute inflammation |
answer
| fast, intense, usually beneficial increased permeability to blood vessels migration of phagocytes (neutrophils and macrophages) tissue repair |
question
| chronic inflammation |
answer
| slow, last a long time, can cause damage |
question
| Fever |
answer
| body temp over 37 C happens when pyrogens trigger hypothalamus to increase the body's core temp chills are associated with fever are due to the reduced blood flow of constricted vessels |
question
| types of pyrogens |
answer
| bacterial endotoxins cytoplasmic contents of bacteria released by lysis antibody-antigen complexes interleukin-1 |
question
| benefits of fever |
answer
| enhances the effects of interferons inhibits growth of some microbes speeds up immune system |
