B. The brain reacts to excessive dopamine levels by increasing the number of dopamine receptors.
there could be harmful chemicals
Answer:
Some substance in the infectious S strain could change the harmless R strain into the more lethal form.
Explanation:
These first type of experiments where crucial to advance in DNA knowledge.
In one experiment, they treated the material with enzymes that destroy all proteins. This is important because scientist notice that there was something else that was causing the strain to change into a lethal form and was heritable (DNA). Know a days we know that plasmids are responsible for such transformation.
Answer: depolarization; hyperpolarization
Explanation:
At resting potential (absence of stimulus), the cell membrane of a neuron is said to be polarized with a net negative charge within due to more potassium (K+) ions present than sodium (Na+) ions.
However, an impressed stimuli reverses the ions content as K+ ions flows out and quickly replaced by Na+ ions, resulting in a decrease in membrane potential and a more positive cell membrane. Thus, depolarization occurs.
An increase in the membrane potential (so that it becomes more negative) is called hyperpolarization.
