[Campbell Biology P.637] What is a key difference between exotoxins and endotoxins? | Practice Question

What is a key difference between exotoxins and endotoxins?

  • A: Exotoxins are lipopolysaccharide components; endotoxins are proteins.
  • B: Exotoxins are released when bacteria die; endotoxins are secreted by living bacteria.
  • C: Exotoxins can cause disease even if bacteria are absent; endotoxins are released when bacteria die.
  • D: Exotoxins are produced by gram-negative bacteria; endotoxins by gram-positive bacteria.

Explanation

The text states that 'Like other exotoxins, the botulinum toxin can produce disease even if the bacteria that manufacture it are no longer present when the food is eaten.' and 'In contrast to exotoxins, endotoxins are released only when the bacteria die and their cell walls break down.'