WorksheetsMicrobial Growth and Nutrition
Total questions: 31
Worksheet time: 32mins
Identify the INCORRECT statements regarding classification of bacteria based on temperature of growth.
(i)Grow at 0-15 °C -Psychrophiles
(ii) Can grow 0-7 °C but optimum between 20-30 °C Psychrotrophs
(iii)Grow at 20-45 °C is Mesophile
(iv) 55-65 °C is Thermophile
(v) Optimum growth at 80 °C & can grow at 113 °C thermophiles
only (v)
all the statements are correct
(i), (ii), (iii) & (iv)
(ii) & (iii)
Arrange the TERMS based on low to high temperature survivors
Psychrophile < psychrotroph < mesophile < hyperthermophile < thermophile
Psychrophile < psychrotroph < mesophile < thermophile < hyperthermophile
psychrotroph < psychrophile < thermophile < hyperthermophile
mesophiles
Match the biomolecules with their respective dominant nutrient elements
(i) fats/lipids - A (C, H, & O);
(ii) proteins - B (C, H, O & P);
(iii) carbohydrates - C (C, H, O, N & P);
(iv) nucleotides - D (C, H, O & N)
(i) - A; (ii) - C; (iii) -D; (iv) -B
(i) - B; (ii) - D; (iii) -A; (iv) -C
(i) - A; (ii) - C; (iii) -B; (iv) -D
(i) - C; (ii) - B; (iii) -D; (iv) -A
Which of the following the main requirement(s) for the bacteria to grow ?
Nutrient requirement
Oxygen requirement
Oxygen and nutrient requirement
Physical and chemical requirement
Identify the characteristic features of micro nutrient
They are required in 0.01 - 1uM quantities
Involved in the enzyme function & protein structure
All of the above
Ca, Mg, Fe are examples
Most Pathogenic Bacteria are Thermophiles
True
False
Bacteria that can grow in the presence or absence of oxygen are called
Facultative Anaerobes
Microaerophiles
Obligate aerobes
Obligate Anaerobes
Most bacteria grow best at pH
14
1
7
9
Which of the following is NOT a chemical requirement of all bacteria?
Nitrogen
Oxygen
Sulphur
Carbon
You inoculate two tubes of liquid culture medium with 100 bacterial cells and incubate one tube at 37°C and the other at 55°C. After 48 hours, there are 20,000 bacteria per milliliter in the 37°C tube and 1,568,000 bacteria per milliliter in the 55°C tube. You conclude that this species is a __________.
Thermophile
Mesophile
Hyperthermophile
Psychrophile
Which of the following is an organic growth factor?
Glucose
Vitamin B1
Peptone
Mg2+
Which bacterium would theoretically be more likely to grow at refrigerator temperatures:
human intestinal pathogen
a soilborne plant pathogen
Most Fungi grow best at pH
1
5
7
9
An experiment began with 4 cells and ended with 128 cells. How many generations did the cells go through?
64
32
6
5
You are required to memorize the amounts of each component in all the culture media studied.
True
False
Figure which line best depicts a facultative anaerobe in the presence of O2?
A
B
C
Both A and B
Which of the following elements is NOT correctly matched with its cellular function?
nitrogen — needed for amino acid synthesis
sulfur — used for synthesis of thiamin and biotin
magnesium and potassium — required as cofactors for enzymes
Phosphorus — used for production of carbohydrates.
phosphorus — incorporated into nucleic acids
Pathogenic bacteria isolated from the respiratory or intestinal tracts of humans are
strict aerobes that grow best in candle jars.
capnophiles that grow best in carbon dioxide incubators.
facultative anaerobes that require reducing media for growth.
strict aerobes that grow best in reducing media.
capnophiles that prefer highly oxygenated growth conditions.
Three cells with generation times of 60 minutes are inoculated into a culture medium. How many cells are there after 5 hours?
64
32
6
5
96
Which enzyme catalyzes the reaction: O2- + O2- + 2H+ → H2O2 + O2?
Catalase
Oxidase
Peroxidase
Superoxide dismutase
A culture medium consisting of agar, peptone, and beef heart is a
Chemically defined medium.
Complex medium.
Selective
Differential
In one hospital, Pseudomonas aeruginosa serotype 10 infected the biliary tract of 10 percent of 1300 patients who underwent gastrointestinal endoscopic procedures. After each use, endoscopes were washed with an automatic reprocessor that flushed detergent and glutaraldehyde through the endoscopes, followed by a tap water rinse. P. aeruginosa serotype 10 was not isolated from the detergent, glutaraldehyde, or tap water. What was the source of the infections?
Bacterial cell walls in the water
A biofilm in the reprocessor
A contaminated disinfectant
Fecal contamination of the bile ducts
Three different culture media are shown above. For the three types of media in Table above, which medium (or media) is/are chemically defined?
A
B
C
A and B
The data shows growth of two bacteria on different media. Based on the data what would you classify Staphylococcus aureus as
Mesophile.
Facultative anaerobe.
Facultative halophile.
Aerobe.
Halophile
Patients with indwelling catheters (long-term tubes inserted into body orifices for drainage, such as through the urethra and into the urinary bladder) are susceptible to infections because
injected solutions are contaminated
their immune systems are weakened
infections can be transmitted from other people.
biofilms develop on catheters.
bacteria cause infections
