Microbiology and Protozoa Quiz

Bacterial Cell Structure

• Capsule is a slimy coating of the bacterial surface that often plays a role in preventing phagocytosis of bacteria.
• Peptidoglycan is one structure of the bacterial cell wall.

Flagella Structure

• Flagella are usually several times longer than the bacterial cell and are composed of a protein called flagellin.

Protozoa Structure

• The outer surface layer of some protozoa is a pellicle.

Protista Reproduction

• Protista reproduces by fission, fragmentation, or conjugation.

T. cruzi Life Cycle

• Infective stage: blood trypomastigote
• Diagnosis stage: blood examination
• Host: humans and animals

Bacterial Cell Wall Differences

Gram-Negative Cell Wall

• Has a thin peptidoglycan layer
• Has an outer membrane containing lipopolysaccharides
• Has a periplasmic space between the peptidoglycan layer and outer membrane

Gram-Positive Cell Wall

• Has a thick peptidoglycan layer
• Lacks an outer membrane
• No periplasmic space between the peptidoglycan layer and plasma membrane