Answer: (A) Natural selection tend to reduce genetic variation as there was a smaller distribution of beak depths, but it tends to select for the most fit phenotypes, as there was an increase in average beak depth after the drought.
Explanation: The picture below shows proof if needed. On USATP
Induced depression of single neurons in brain areas with opiate receptors
- Enkephalin, applied microiontophoretically, depressed spontaneous and glutamate-induced firing of one neuron in frontal cortex, caudate nucleus, and periaqueductal gray matter, where enkephalin and high concentrations of opiate receptors are met.
- More than one depressions were blocked by the specific narcotic antagonist naloxone. The results are durable with a neurotransmitter or neuromodulator role for this new brain pentapeptide.
- Opium derivatives have been in medical use for the last 2000 years, and may be longer than any other class of drugs
- . The brain regions which was involved in these actions have been identified in some instances by local microinjection of pmole quantities of opioids.
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A sea breeze is most intense during mid to late afternoon
