D311 Microbiology – 100 Question NEWEST Mock Exam questions with correct answers aready graded A+ |THE BEST

D311 Microbiology – 100 Question
NEWEST Mock Exam questions with
correct answers aready graded A+ |THE
BEST
Section 1: Cell Structure & Function

1. Which structure is unique to prokaryotes?
A. Nucleus
B. Mitochondria
C. Nucleoid
D. Golgi apparatus
Answer: C
Rationale: Prokaryotes lack membrane-bound organelles; DNA resides in the nucleoid.



2. Gram-positive bacteria have:
A. Outer membrane
B. Thin peptidoglycan
C. Thick peptidoglycan
D. No cell wall
Answer: C
Rationale: Thick peptidoglycan retains crystal violet stain.



3. The function of bacterial capsule is:
A. Energy production
B. Protection from phagocytosis
C. Protein synthesis
D. DNA replication
Answer: B
Rationale: Capsules enhance virulence by preventing immune attack.



4. Ribosomes in bacteria are:
A. 80S
B. 70S
C. 60S
D. 50S

, Answer: B
Rationale: Prokaryotic ribosomes are smaller (70S).



5. Flagella are used for:
A. Attachment
B. DNA transfer
C. Motility
D. Protection
Answer: C
Rationale: Flagella provide movement.



6. Gram-negative bacteria contain:
A. Teichoic acids
B. Lipopolysaccharide (LPS)
C. Thick peptidoglycan
D. No membrane
Answer: B
Rationale: LPS is part of the outer membrane.



7. Pili are mainly used for:
A. Movement
B. Photosynthesis
C. Conjugation
D. Digestion
Answer: C
Rationale: Sex pili transfer DNA between bacteria.



8. Which is NOT found in prokaryotes?
A. Plasma membrane
B. Ribosomes
C. Mitochondria
D. Cytoplasm
Answer: C
Rationale: Prokaryotes lack membrane-bound organelles.



9. Acid-fast bacteria have:
A. No cell wall
B. Mycolic acid
C. Thick capsule only