BIO210
Microbiology
Midterms Exam Review (Qns & Ans)
2025
1. Which of the following mechanisms is responsible for
bacterial resistance to antibiotics?
- A. Increased permeability of the bacterial cell wall
- B. Production of beta-lactamase enzymes
- C. Enhanced ribosomal binding of antibiotics
- D. Decreased efflux pump activity
ANS: B. Production of beta-lactamase enzymes
Rationale: Bacteria produce beta-lactamase enzymes that
break down beta-lactam antibiotics, rendering them ineffective.
©/2025
,2. What is the primary function of the bacterial cell wall?
- A. Protein synthesis
- B. Genetic material replication
- C. Maintaining cell shape and protection
- D. Energy production
ANS: C. Maintaining cell shape and protection
Rationale: The bacterial cell wall provides structural support,
maintains cell shape, and protects the cell from osmotic pressure.
Fill-in-the-Blank Questions
3. The __________ cycle involves the integration of viral DNA
into the host genome, where it can remain dormant before
becoming active.
ANS: Lysogenic
Rationale: The lysogenic cycle involves the integration of
viral DNA into the host genome, where it can remain dormant
before becoming active and entering the lytic cycle.
©/2025
, 4. __________ are unicellular eukaryotic microorganisms that
can cause diseases such as malaria and amoebic dysentery.
ANS: Protozoa
Rationale: Protozoa are unicellular eukaryotic
microorganisms that can cause diseases such as malaria (caused
by Plasmodium spp.) and amoebic dysentery (caused by
Entamoeba histolytica).
True/False Questions
5. True or False: Gram-positive bacteria have a thick
peptidoglycan layer in their cell walls, which retains the crystal
violet stain during the Gram staining procedure.
ANS: True
Rationale: Gram-positive bacteria have a thick peptidoglycan
layer that retains the crystal violet stain, appearing purple under a
microscope after the Gram staining procedure.
6. True or False: Viruses can replicate independently of a host
cell.
ANS: False
©/2025
Microbiology
Midterms Exam Review (Qns & Ans)
2025
1. Which of the following mechanisms is responsible for
bacterial resistance to antibiotics?
- A. Increased permeability of the bacterial cell wall
- B. Production of beta-lactamase enzymes
- C. Enhanced ribosomal binding of antibiotics
- D. Decreased efflux pump activity
ANS: B. Production of beta-lactamase enzymes
Rationale: Bacteria produce beta-lactamase enzymes that
break down beta-lactam antibiotics, rendering them ineffective.
©/2025
,2. What is the primary function of the bacterial cell wall?
- A. Protein synthesis
- B. Genetic material replication
- C. Maintaining cell shape and protection
- D. Energy production
ANS: C. Maintaining cell shape and protection
Rationale: The bacterial cell wall provides structural support,
maintains cell shape, and protects the cell from osmotic pressure.
Fill-in-the-Blank Questions
3. The __________ cycle involves the integration of viral DNA
into the host genome, where it can remain dormant before
becoming active.
ANS: Lysogenic
Rationale: The lysogenic cycle involves the integration of
viral DNA into the host genome, where it can remain dormant
before becoming active and entering the lytic cycle.
©/2025
, 4. __________ are unicellular eukaryotic microorganisms that
can cause diseases such as malaria and amoebic dysentery.
ANS: Protozoa
Rationale: Protozoa are unicellular eukaryotic
microorganisms that can cause diseases such as malaria (caused
by Plasmodium spp.) and amoebic dysentery (caused by
Entamoeba histolytica).
True/False Questions
5. True or False: Gram-positive bacteria have a thick
peptidoglycan layer in their cell walls, which retains the crystal
violet stain during the Gram staining procedure.
ANS: True
Rationale: Gram-positive bacteria have a thick peptidoglycan
layer that retains the crystal violet stain, appearing purple under a
microscope after the Gram staining procedure.
6. True or False: Viruses can replicate independently of a host
cell.
ANS: False
©/2025
