The rose bushes in your garden have flat brown spots on thei…
The rose bushes in your garden have flat brown spots on their leaves that you suspect are due to an infection by Rosilla freckulus. Based on your knowledge of Koch’s postulates, what is the correct order of steps to be performed to prove that these bacteria are responsible for this plant disease. 1. Grow Rosilla freckulus in pure culture 2. Isolate Rosilla freckulus from all the diseased bushes 3. Reisolate Rosilla freckulus in pure culture 4. Reproduce the disease in the new hosts5. Inoculate undiseased rose bushes with Rosilla freckulus
Read DetailsCase Study 2: An 85-year-old male was admitted to the emer…
Case Study 2: An 85-year-old male was admitted to the emergency room of a New York City hospital suffering from breathing difficulties and coughing. He had a high fever, cough, and chest pain. He had presented to his local physician 3 days previously complaining of fever, headache, malaise, and pneumonia-like respiratory symptoms. A year ago he moved into a large long-term care facility after his wife died and he has been suffering from type two diabetes for the last thirty years. Sputum was collected for culture and sensitivity. A sputum gram stain indicated the presence of many white blood cells and pleomorphic gram-negative coccobacilli. The organism causing the infection did not grow on the traditional media for sputum culture. An additional urine specimen for antigen testing was then collected and sent to a reference laboratory to confirm the diagnosis. Case Study 2 Question 2: If he did not contract his illness from another patient, what is the likely mode of transmission?
Read DetailsCase Study 3: A 3-year old girl presented at the emergency r…
Case Study 3: A 3-year old girl presented at the emergency room with bloody diarrhea, fever and vomiting. The child’s mother reported that the day-care center called yesterday morning because she started having a watery diffuse diarrhea. That night she began to complain of severe cramps and her diarrhea became bloody and pus-filled. The family has no recent travel history and while they are vegetarians, they only consume pasteurized milk, cheese, and egg products. The gram stain showed many white blood cells and many gram-negative bacilli. The culture resulted in many translucent-clear colonies on the MacConkey’s agar that were oxidase negative and fermented glucose, but not lactose. She was admitted to the hospital to treat her dehydration and for observation. Case Study 3 Question 1: What was the most likely etiologic agent of infection in this patient?
Read DetailsTwo blocks are connected by a massless rope over a frictionl…
Two blocks are connected by a massless rope over a frictionless, massless pulley. Block m1 hangs freely, while block m2 rests on a horizontal, frictionless surface. m1=[m1] kg, and m2=[m2] kg. A horizontal force F=[F] N is applied to m2. What is the magnitude of the tension in the rope? Express your answer in newtons (N).
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