1. The genetic material of a prokaryote is present in the ______________
a) Nucleus
b) Cytoplasm
c) Nucleoid
d) Plasmid
Explanation: Bacteria does not contain a true nucleus. Nucleoid is a poorly demarcated region of the cell that contains the bacterial genetic material or bacterial DNA.
2. Which of the following is not true for both prokaryotic and eukaryotic cells?
a) Same composition of plasma membrane
b) Both contain shared metabolic pathways
c) Genetic information encoded in DNA with similar genetic code
d) Both contain Golgi apparatus for protein trafficking
Explanation: Prokaryotic cells do not have organelles such as Golgi Apparatus. However, the composition of plasma membrane is the same. The metabolic pathways such as TCA cycle and glycolysis take place in both. Both contain DNA as the genetic material.
3. Which of the following is present in both prokaryotic and eukaryotic cells?
a) Proteasomes
b) Plasmids
c) Lysosomes
d) Peroxisomes
Explanation: Proteasomes and protein digesting structures present in both archaebacteria and eukaryotes. Proteasomes degrade unnecessary and damaged proteins by proteolysis. Plasmids are double stranded circular DNA found in prokaryotes whereas lysosomes and peroxisomes are only found in eukaryotes.
4. Which of the following polysaccharide is not present in the eukaryotic plant cell wall?
a) Cellulose
b) Chitin
c) Hemicellulose
d) Pectin
Explanation: Chitin is a polysaccharide that is present mainly in exoskeletons of Arthropods and are not a component of plant cell wall. Plant cell wall is majorly composed of cellulose, hemicelluloses and pectin.
5. Pseudopeptidoglycan is a found in the cell wall of _______________
a) Fungi
b) Archaea
c) Bacteria
d) Protozoa
Explanation: Pseudopeptidoglycan is a cell wall component of some Archaea. It differs from bacterial peptidoglycan in chemical composition but has similar physical structure and function as that of bacterial peptidoglycan.
6. Biofilms are ________________
a) Thin polymeric films made of biopolymer
b) Strings of protein filaments
c) Complex, multispecies communities
d) A metabolic product for prokaryotic organisms
Explanation: Prokaryotes such as bacteria were initially thought to be solitary creatures, but they are capable of living as complex communities called as biofilms. A biofilm is defined as a group of microorganisms in which cells stick or adhere to a living or non-living surface. These adherent cells become embedded within a slimy extracellular matrix composed of extracellular polymeric substances (EPS).
7. Escherichia coli commonly inhabit the _______________ place.
a) Human endodermal layer
b) Human digestive tract
c) Human bronchioles
d) Human skin surface
Explanation: Escherichia coli or E.coli is a Gram negative, facultatively anaerobic, rod-shaped bacteria. It mainly inhabits the human digestive tract and is commonly found in the lower intestinal regions of warm-blooded animals such as humans.
8. How many basal body rings do Gram positive bacteria have in the flagella?
a) 2
b) 3
c) 4
d) 1
Explanation: Gram positive bacteria have 2 basal rings in the flagella, one in the peptidoglycan layer and one in the plasma membrane. Gram negative bacteria have 4 basal rings in their flagella. The L ring is located in the plane in the outer membrane, P ring in the plane of peptidoglycan around flagellar rod, MS ring that is located within and above cytoplasmic membrane and C ring extends into the cytoplasm.
9. The rotary engine made of protein at the base of the flagella is driven by ______________
a) Vanderwaal’s foce
b) Proton- motive force
c) Electron passage
d) Exchange of sodium and potassium ions
Explanation: Proton motive force is the flow of protons or hydrogen ions across the bacterial cell membrane due to a concentration gradient set up by cell’s metabolism. This force drives the motor engine at the base of the flagella and helps in flagellar movement.
10. The following diseases is caused by viruses ____________
a) Influenza
b) Measles
c) Typhoid
d) Both Influenza and Measles
Explanation: Measles and Influenza are diseases caused by the infection of viruses. Typhoid is caused by a bacteria known as Salmonella typhi.