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BHS 329 Midterm Comprehensive Exam Questions And Answers Latest Updated
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Pathogenicity - ✔✔qualities that promote the production of disease Virulence - ✔✔potency of the pathogen indicated by the ratio of the number of cases compared to number of exposures Infectivity - ✔✔proportion of exposures needed to cause infection in an individual Toxigenicity - ✔✔ability of the pathogen to produce harmful toxins that increase host cell and tissue damage Antigenicity - ✔✔level to which a pathogen is viewed by the host immune system as foreign Antigenic variability - ✔✔process of eluding the human host defenses, often consists of altering antigen presentation Pathogenic defense mechanisms - ✔✔ways in which a pathogen has developed to avoid destruction by host Coinfection - ✔✔hosting two or more pathogens simultaneously Superinfection - ✔✔when an infection arises in addition to one that is already present Endotoxin - ✔✔complex of phospholipid-polysaccharide molecules that form the structural component of the gram-negative cell wall, causes inflammatory response when bacterium is lysed Exotoxins - ✔✔potent substances that result in host cell dysfunction or lysis
Neisseria meningitidis - ✔✔meningitis Streptococcus pyogenes - ✔✔- septicemia
- myositis
- necrotizing fascitis Streptococcus pneumoniae - ✔✔- pneumonia
- meningitis
- otitis media Staphylococcus aureus - ✔✔- endocarditis
- cellulitis
- pneumonia
- osteomyelitis
- septicemia Escherichia coli - ✔✔- urogenital tract infection
- diarrhea Salmonella typhi - ✔✔- enterocolitis
- bacteremia
- typhoid
- localized infections Pseudomonas aeruginosa - ✔✔- urinary infection
- wound infection Rickettsiae - ✔✔bacteria -- obligate intracellular parasites
Transmission of protozoa - ✔✔- sexual contact
- contaminated food or water
- via arthropods Communicable disease - ✔✔diseases spread from person to person Cause of communicable disease - ✔✔microorganisms that live and reproduce in a human host Autoclave - ✔✔device that uses steam heat at high pressures to sterilize objects Direct contact transmission - ✔✔physically touching a disease reservoir or exposure to infected bodily fluids Droplet transmission - ✔✔transmission via airborne droplets across no more than 3 feet Airborne transmission - ✔✔inhalation of infective respiratory particles that are suspended in the air Vector transmission - ✔✔transmission via a carrier vehicle (eg. arthropods) Universal precautions - ✔✔standard of health care that recognizes all blood and body fluids as potentially infective Rules of universal precaution - ✔✔- health care workers wear gloves when having any contact with body fluids
- masks and protective eyewear are to be worn if splattering is anticipated Stages of acute infection - ✔✔1. Exposure
- Incubation
- Prodrome
- Acute clinical illness
- Convalescence
- Exposure - ✔✔contact with the pathogen through any mode of transmission
- Incubation - ✔✔period of time between exposure and onset of signs/symptoms During which phase of acute infection is transmission risk the highest? - ✔✔Incubation
- Prodrome - ✔✔onset of nonspecific signs of symptoms including fatigue, low fever, nausea, weakness
- Acute clinical illness - ✔✔manifestation of signs and symptoms that are specific to a given disease During what phase of acute infection is diagnosis most accurate? - ✔✔Acute clinical illness
- Convalescence - ✔✔period of time between waning clinical manifestations and full recovery from disease Septicemia - ✔✔occurs when microorganisms gain access to the blood and circulate throughout the body Bacteremia - ✔✔septicemia caused by bacteria Septic shock - ✔✔process of systemic vasodilation due to severe infection Chronic infection - ✔✔infection that lasts for several weeks to years Purulent - ✔✔containing pus
Pathogens - ✔✔disease-producing microbes Horizontal spread - ✔✔one individual infects others, insect vectors, etc. Vertical spread - ✔✔parents to offspring via sperm, ovum, placenta, milk Eye immune strategies - ✔✔washing and antibiotic activity of tears Lymph node immune strategies - ✔✔phagocytosis by macrophages, attack by natural killers cells Skin immune strategies - ✔✔physical barrier Respiratory immune strategies - ✔✔- entrapment by mucus
- transport to throat via cilia
- phagocytosis by alveolar macrophages Blood immune strategies - ✔✔- phagocytosis by macrophages and granulocytes
- digestion by lysozymes
- attack by complement proteins Bone marrow immune strategies - ✔✔- phagocytosis by macrophages and granulocytes
- attack by natural killer cells Liver immune strategies - ✔✔phagocytosis by Kupffer cells (specialized macrophages) Spleen immune strategies - ✔✔- phagocytosis by macrophages
- attack by natural killer cells
Gastroenteric immune strategies - ✔✔- destruction by gastric acid, bile, and enzymes
- competition for nutrients by billions of normal bacteria Urogenital tract - ✔✔flushing and acidity of urine 6 links in the chain of infection - ✔✔- infectious agent
- reservoirs
- portal of exit
- means of transmission
- portal of entry
- susceptible host Average volume of blood - ✔✔5.5 L What percentage of blood is plasma? - ✔✔50-55% 2 most prevalent blood proteins - ✔✔albumin (60%), globulins (alpha, beta, gamma) Erythrocyte flexibility - ✔✔ 10 micrometer diameter, but fit through 1-2 micrometer capillaries 2 methods of moving O2 in blood - ✔✔1. dissolved in plasma
- bound to hemoglobin Myoglobin - ✔✔a single polypeptide chain with one O2 binding site Cyanosis - ✔✔when hemoglobin releases oxygen and becomes desaturated, it turns a deep purple
to which region of the lymph node do B cells migrate? - ✔✔cortex and medulla to which region of the lymph node do T cells migrate? - ✔✔paracortex atrophy - ✔✔decrease in the size of cells hypertrophy - ✔✔increase of cell size (trophic signaling) hyperplasia - ✔✔increase in cell number metaplasia - ✔✔swapping of one cell type for another dysplasia - ✔✔change in cell size, shape, uniformity, arrangement, and structure autophagy - ✔✔mechanism by which the cell 'eats itself' by digesting its own organelles necrosis - ✔✔cell death with lysis of membrane, leads to inflammation apoptosis - ✔✔programmed cell death with intact membrane, no secondary inflammation pyroptosis - ✔✔inflammatory cell death What percentage of your weight is total body water (TBW)? - ✔✔60% at steady state, how do extracellular fluid osmolality and intracellular osmolality compare? - ✔✔they are equal osmolarity - ✔✔number of solute particles per L of water, it is temperature dependent
osmolality - ✔✔mols per kilogram of water factors that change ECF and ICF - ✔✔- ingestion of water
- dehydration
- intravenous infusion of solutions
- loss of fluid
