Question

QUESTION 21

1. Critical results from the microbiology department must be communicated to the clinician immediately. All of the following results are considered critical except:

   	a.	positive spinal fluid gram stain on culture
   	b.	blood smear for malaria
   	c.	negative acid fast stain
   	d.	Streptococcus pyogenes from a surgical wound

QUESTION 22

1. The tech working on an aerobic wound culture is identifying a colony that is large, gray, and non-hemolytic on blood agar. The tech prepares a gram stain of the colony and notices a consistency similar whisked egg whites. The gram stain reveals a large gram-positive Bacillus. What is the most likely identification of this colony?

   	a.	Bacillus anthracis
   	b.	Burkholderia mallei
   	c.	Bacillus cereus
   	d.	Fransicella tularensis

QUESTION 23

1. Which of these describes the mode of action of the antibiotic beta-lactam class of antibiotics?

   	a.	inhibits DNA synthesis
   	b.	inhibits RNA synthesis
   	c.	inhibits protein synthesis
   	d.	inhibits cell wall synthesis

Answer 1

1. Option C -negative acid fast stain

A normal result for an acid-fast bacteria smear is negative, meaning no bacteria were found in the sputum sample.

2.Option C -Bacillus cereus

Bacillus cereus is a bacteria commonly found in soil. It causes food poisoning when people eat contaminated foods like meats, sauces, soups, or vegetables that haven't been stored properly. They multiply quickly and produce toxins that cause diarrhea and vomiting.Bacillus cereus -Filamentation phenomenon consisting of intertwined beaded bacilli as shown in Gram stains of agar cultures. Colony MorphologyWhen grown under aerobic conditions on 5% sheep blood agar at 37°C, B. cereus colonies are dull gray and opaque with a rough matted surface

3. Option D -inhibits cell wall synthesis

β-Lactam antibiotics are a broad class of antibiotics that includes penicillin derivatives.Penicillins and cephalosporins are the major antibiotics that inhibit bacterial cell wall synthesis.