Knockout Mice That Lack Either the Gene for the Precursor

question 47

Multiple Choice

Knockout mice that lack either the gene for the precursor for substance P or the gene for the substance P receptor exhibit

• A) total insensitivity to pain stimuli.
• B) insensitivity to mildly painful stimuli but normal responses to intensely painful stimuli.
• C) insensitivity to intensely painful stimuli but normal responses to mildly painful stimuli.
• D) exaggerated responses to mildly painful stimuli.