Topic 1: Bacterial Classification, Morphology and Ultrastructure

Which of the following organisms is prokaryotic?

• Fungi

• Bacteria

• Protozoa

• Viruses

What is the genetic material of prokaryotes?

• Linear DNA in nucleus

• RNA only

• Circular DNA in cytoplasm

• DNA in ribosomes

What organelle is absent in prokaryotes?

• Ribosome

• Mitochondria

• Cell wall

• Cytoplasmic membrane

What is the size of bacterial ribosomes?

• 80S

• 60S

• 50S

• 70S

What is the basic shape of Neisseria gonorrhoeae?

• Spirillum

• Bacillus

• Coffee-bean shaped cocci

• Comma-shaped

Which of the following bacteria is lancet-shaped?

• E. coli

• Streptococcus pneumoniae

• Treponema pallidum

• Bacillus anthracis

Which is an example of a comma-shaped bacterium?

• Borrelia

• Vibrio cholerae

• Streptococcus

• Corynebacterium

Which structure enables a bacterium to evade phagocytosis?

• Cell wall

• Ribosome

• Capsule

• Flagella

Which of the following is found only in Gram-positive bacteria?

• Outer membrane

• Teichoic acid

• Lipopolysaccharide

• Porins

Which dye is the primary stain in Gram staining?

• Safranin

• Crystal violet

• Methylene blue

• Carbol fuchsin