Answer to Question 1
Answer: Pain signals are transmitted to the spinal cord and from there to the thalamus and to various cortical regions (anterior cingulate, primary and secondary somatosensory cortex). Pain reactivity can be diminished by interrupting the ascending pain pathways, by reducing the activity of the anterior cingulate cortex (reduced aversiveness), or by activating a descending neural circuit from the PAG to the spinal cord.
Answer to Question 2
Answer: Taste receptors code for five qualities (sweetness, bitterness, sourness, saltiness, and umami). Each receptor type involves a different transduction process. Hydrogen ions generate a sour taste, which controls a potassium channel. Bitter and sweet tastes are coded for by receptors containing gustducin and that reduce cyclic AMP. Sweet receptors also are coded by gustducin receptors but increase cyclic AMP. The umami signal involves a specific glutamate receptor (mGluR4). The pleasant taste of fat seems linked to receptors that detect free fatty acids in foods.
Step 2 of gene cloning: The actions of a restriction enzyme and DNA ligase to produce a recombinant
Conduction of pain impulses.
Bones of the lower extremity.
The Three Components of Pain
Biological Diversity: Complex patterns of diversity
Gel electrophoresis, an essential laboratory technique in biological science research