How can normal flora be a barrier to entry?
A. They activate the complement system, which punches holes in the invading pathogen.
B. They use up nutrients and release wastes, preventing pathogenic bacteria from gaining a foothold.
C. They cause an inflammatory response that kills pathogenic bacteria upon contact.
D. They release histamine, which causes blood vessels to become permeable.
E. They phagocytize any pathogenic bacteria that attempt to infect.
Answer: B
You might also like to view...
Which term is used to describe the overall 5?-to-3? direction of linked nucleotides in a DNA chain?
A) complementarity B) sequence C) polarity D) primacy
Alligators excavate holes in the bottom of bodies of water. During times of severe drought these holes act as refugia for various aquatic organisms that might perish if there were no water available. Thus, alligators in this system can be classified as a(n)
A. keystone species. B. symbiotic species. C. sympatric species. D. allopatric species. E. refugistic species.
If a human gene mRNA were placed into a cell of yeast, it would be:
a. degraded immediately. b. translated into a repeating amino acid chain. c. translated into a chain of random amino acids not resembling the protein in humans. d. translated into the protein that is found in humans. e. integrated into the genome of the yeast.
The formation of a peptide bond between two amino acids is an example of a(n) ______________reaction.
A) cleavage B) condensation C) group transfer D) isomerization E) oxidation reduction