1. Which of the following is not the characteristic of a growth curve?

A. Shows development of microbial population under relatively stable environmental conditions
B. Plotted with logarithmic numbers
C. Graphs numbers of microbes versus time
D. Each growth curve consists of four distinct phases

2. Generation time of Escherichia coli is

A. 20 minutes
B. 20 hours
C. 20 days
D. 200 hours

3. The organism which obtains their energy from chemicals are designated as

A. prototrophs
B. chemotrophs
C. organotrophs
D. autotrophs

4. Nutrient content and biological structures are considered as

A. implicit factor for microbial growth
B. intrinsic factor for microbial growth
C. processing factor
D. none of the above

5. The organism which grows best above 45°C are called

A. psychrophilic
B. mesophilic
C. thermophilic
D. any of these