Exam #5 Micro

Please choose the answers that correctly describe the virulence factors of Staphylococcus aureus.

-Coagulase enzyme causes blood plasma to clot. -Penicillinase enzyme allows S. aureus to grow in the presence of penicillin. -Hyaluronidase enzyme promotes invasion of host tissues.

Please select the diseases that are often caused by S. pyogenes.

-impetigo -pharyngitis -necrotizing fasciitis

Please match the staphylococcal disease with its symptom.

1. Organ damage/shutdown= Toxic shock syndrome 2. Localized abscesses= Boils 3. Vomiting Food= intoxication 4. Bone infection= Osteomyelitis

Please match the description to the disease pattern that it describes.

1. a disease pattern in which the number of new cases is increasing beyond what is expected for the population= Epidemic 2. a disease pattern in which the number of new cases is increasing beyond what is expected, not just in a limited geographic area or population, but on more than one continent= Pandemic 3. a disease pattern in which occasional cases are reported at irregular intervals in random locations= Sporadic 4. a disease pattern with a relatively stable frequency over a long time period= Endemic

Please match the description to the pattern of infection.

1. more severe infection, rapid onset: Acute infection 2. an infection that has spread to multiple body sites and tissue fluids; no longer restricted to one body site: Systemic infection 3. Microbe enters the body and remains confined to a specific tissue: Localized infection . 4. an infection that progresses and persists over a longer period of time; symptoms often less severe: Chronic infection 5. a subsequent infection with a different microbe that may occur following an initial infection: Secondary infection

Please choose the statement that provides correct information about zoonoses.

70 percent of the new emerging infections seen today are zoonoses.

A patient has a deep wound infection, and the specimen taken for microbial identification in the lab is a tissue sample from within the wound. Please choose the most likely organism causing the infection.

Clostridium

Please match the term to the statement that most accurately describes it to test your understanding of colonization, infection, and disease.

Colonization:Presence of organisms living in or on the body, but not causing any pathology Infection: Pathogenic microorganisms penetrate the host defenses, enter the tissues, and multiply. Infectious disease:Disruption of a tissue or organ caused by microbes or their products

Helicobacter pylori is able to withstand the harsh conditions of the stomach because it develops a thick walled cyst when conditions become highly acidic.

False

Please select the pathogen from the genus Streptococcus that correctly represents the most serious pathogen of this group.

Group A beta-hemolytic S. pyogenes

Please choose the answer that explains how the chemical leukocidin, produced by S. aureus, affects the host.

Inflammation and phagocytosis are severely compromised.

Please choose the statement that best describes the benefits of microbial antagonism to the human host.

Microbial antagonism occurs when members of the normal microbiota prevent pathogens from colonizing and becoming established in the body.

Please select the pathogenic species of Neisseria.

N. meningitidis N. gonorrhoeae

Please choose the best explanation for why Helicobacter is able to live in the harsh conditions of the stomach.

One of its enzymes converts urea into ammonium and bicarbonate.

Occasionally, an episode of food poisoning occurs which centers around processed ham, sausage, or salted pork. These episodes are almost always assumed to be due to ingestion of Staphylococcus aureus unless other evidence proves differently. This is because

Staphylococcus aureus is responsible for most episodes of food poisoning.

Why is antibiotic use a common cause of Clostridium difficile infections?

The antibiotic wipes out the normal bacteria in the gut, allowing C. difficile to overgrow.

The patient is a 34-year-old man, who is complaining of night sweats, weight loss, diarrhea, and fatigue. He is diagnosed with Mycobacterium avium complex. Please select the explanation that describes why this patient might have this disease.

The patient has AIDS

John has been diagnosed with gonorrhea and he is worried about his ex-girlfriend, with whom he had been having sex. But she hasn't said anything about it to him, so he just decides to not say anything. Please choose the statement that best explains why his girlfriend does not have symptoms.

The rate of symptoms, particularly in women, can be very low.

Please choose the feature of Pseudomonas that makes it a difficult organism to control in a hospital environment.

antibiotic resistance

The pneumonia caused by Mycoplasma is referred to as _______ pneumonia because the disease is mild, the bacteria cannot be easily seen nor cultured, and the target population is different than the one for common pneumococcal pneumonia.

atypical

Please choose the answer that best fills in the blanks of this sentence in the correct order. A mosquito which transmits malaria by injecting infected saliva into the blood of its victim is an example of a ______ vector, whereas a fly which transmits trachoma on its feet as it moves from one infected individual to the eye area of a noninfected individual is an example of a ______ vector.

biological; mechanical

Please choose the correct mechanism of botulinum toxin.

blocks the release of acetylcholine neurotransmitter from the axon foot vesicles so muscle cannot get message to contract

The O antigen of Enterobacteriaceae cell walls consists of lipopolysaccharide, which has a lipid portion referred to as _________.

endotoxin

The study of the frequency and distribution of disease in defined human populations is known as _________.

epidemiology

Please select all of the organs of the body that can be affected by the genus Chlamydia.

eyes heart brain reproductive organs liver

Please choose all of the correct symptoms which describe meningococcal meningitis.

headache insanity very high blood pressure stiff neck

Please order the following events to reflect the progression of tuberculosis.

inhalation of bacteria= 1 Bacteria are localized within lung tissue by phagocytic macrophages= 2 Immune cells migrate to the area and surround the macrophages and bacteria.= 3 latent infection= 4 Bacteria migrate out of tubercles into healthy lung tissue= 5 wasting of body= 6

Please choose the answers that best fills in the blanks of this sentence in order. The ability of a microbe to cause disease is called ________, whereas _______ refers to the degree to which a microbe can cause disease, or the relative capacity of a pathogen to invade and harm host tissues.

pathogenicity; virulence

The primary habitat in the natural world from which a pathogen originates is its ________.

reservoir

Please order the following choices to reflect the progression of whooping cough symptoms, starting with the infection.

respiratory tract= 1 buildup of mucus along respiratory tract= 2 destruction of ciliated epithelial cells along congestion and sneezing= 3 sudden coughs with gasping breath intake= 4