1. What is the color of colonies of Staphylococcus aureus?
a) Pink
b) Red
c) Violet
d) Gold
Explanation: Staphylococcus aureus produces and retains water-insoluble pigments which give golden color to their colonies.
2. Pyoverdin is which type of pigment?
a) water-insoluble pigment
b) water-soluble pigment
c) fluorescent pigment
d) sparingly water-soluble pigment
Explanation: Pyoverdin is a fluorescent pigment and is water-soluble in which the agar medium around the colonies glows white or blue-green when exposed to ultraviolet light. It is produced by P.aeruginosa.
3. Growth in broth cultures occurs mainly in the form of__________
a) slightly turbid
b) heavy surface pellicle
c) sediment
d) viscous
Explanation: Growth in broth cultures occurs mainly in the form of a heavy surface pellicle and the medium below the pellicle is only slightly turbid.
4. Which bacteria among the following produces a water-insoluble pigment?
a) Mycobacterium kansasii
b) Pseudomonas aeruginosa
c) Chromobacterium violaceum
d) Pseudomonas chlororaphis
Explanation: Chromobacterium violaceum produces a water-insoluble pigment which causes its colonies to become violet in color.
5. The respiratory chain of bacteria is associated with the _____________
a) mitochondrial membrane
b) cytoplasmic membrane
c) cell wall
d) cytoplasm
Explanation: The respiratory chain of bacteria is associated with the cytoplasmic membrane and that of eukaryotes is present in the mitochondrial membrane.
6. The prosthetic group of a cytochrome contains how many iron atoms?
a) one
b) two
c) three
c) four
Explanation: Cytochromes are a major class of oxidative enzymes whose prosthetic group is a derivative of heme and contains a single iron atom, which is responsible for the oxidative or reductive properties of the enzyme
7. Among the following which can directly react with oxygen?
a) cytochrome c
b) cytochrome c1
c) cytochrome a
d) cytochrome a3
Explanation: Cytochrome a and a3 together are called cytochrome oxidase, both of them contain copper. But only cytochrome a3 can react directly with oxygen.
8. How many ATP molecules are formed for per molecule of FADH2 reoxidized?
a) 3
b) 1
c) 2
d) 4
Explanation: Three ATP are formed per molecule of NADH2 reoxidized but only two ATP molecules are formed per molecule of FADH2 reoxidized, because of the high energy of NADH2.
9. In photosynthesis by green plants, algae, cyanobacteria which of the following acts as terminal electron acceptor?
a) Water
b) Oxygen
c) NADP+
d) FAD+
Explanation: In photosynthesis by green plants, algae and cyanobacteria, water serves as a primary electron donor and NADP+ as a terminal electron acceptor.
10. In aerobic respiration the terminal electron acceptor is oxygen, nitrate, sulfate, etc.
a) True
b) False
Explanation: In aerobic respiration the terminal electron acceptor is oxygen; in anaerobic respiration the final electron acceptor is nitrate, sulphate and carbonate.