Microbiology Answers

Why does penicilin cause so few side effects while amphotericin B causes so many? Consider the structure of prokaryotic and eukaryotic cells when giving your answer?

what is the difference between yeast and filamentous fungi based on reproduction?

A particular poison works by interfering with the enzyme required to synthesize tRNA. At which step in protein synthesis will the process be stopped?

Initiation

Elongation

Termination

Replication

Q.15 Thermal death of viable spores of Bacillus subtilis in a food sample follows a first order kinetics
with a specific death rate constant of 0.23 min-1
at 100°C. The time (in minutes) required to kill
99% of spores in the food sample at 100°C will be
(A) 10 (B) 20 (C) 23 (D) 60
Q.16 How much skim milk (in kg) containing 0.1% fat should be added to 500 kg of cream containing
50% fat to produce standardized cream containing 36% fat?
(A) 140 (B) 165 (C) 195 (D) 210

Q.20 An enzyme catalyzed reaction (following Michaelis-Menten kinetics) exhibits maximum reaction
velocity (Vm) of 75 nmol l
-1
min-1
.

The enzyme at a substrate concentration of 1.0x10-4
M shows the
initial reaction velocity of 60 nmol l
-1
min-1
. The Km value of the enzyme in molar concentration
(M) is
(A) 2.5 x 10-5
(B) 5.0 x 10-5

(C) 2.5 x 10-4
(D) 5.0 x 10-4

Q.18 A cold storage plant is used for storing 50 tonnes of apples in perforated plastic crates. During the
storage, apples are cooled down from 28°C to storage temperature of 2°C. (Specific heat of the
apple = 0.874 kCal kg-1
°C-1
). If the required cooling is attained in 16 hours, the refrigeration plant
capacity (in Tons) is
(A) 19 (B) 24 (C) 29 (D) 32
Q.19 An actively growing culture of Acetobacter aceti is added to the vigorously aerated fermented fruit
juice medium containing 10 g l
-1
ethanol to produce vinegar. After some time, the ethanol
concentration in the medium is 0.8 g l
-1
and acetic acid produced is 8.4 g l
-1
.

What is the conversion
efficiency of the process with respect to theoretical yield?
(A) 30 (B) 50 (C) 70 (D) 90

Using light microscopy you examine the soil samples and the goo from the degraded polyurethane. Will this approach allow you to observe all microorganisms present in the sample ? why or why not ? What are the limitations of this approach?

tell me calculation of Colony forming unit for product. i prepared serial dilution 10 ml sample in 90ml i.e1:10 ratio, transfer 1ml into 9ml saline i.e 1:100, i got 4 colony in 1:10, 2 colony in 1:100 dilution

why an organism fail to grow?

If the hyphae are spread out, the fungus _____.