All of these answers are true of A-B exotoxins except __________.

A) tThe B portion of the toxin binds to surface receptors on host cells
B) they consist of two polypeptide components
C) many exotoxins are A-B toxins
D) the A portion of the toxin is the active component
E) they are produced only by gram-negative bacteria


Ans: E) they are produced only by gram-negative bacteria

Biology & Microbiology

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Which of the following statements best describes the gametes of most animals?

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An action potential is an abrupt and transient change in the membrane potential of an excitable cell

1.True 2.False

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Which of the following is not a hormone that uses the mechanism of action of peptide hormones?

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Biology & Microbiology