Answer:
In the mentioned scenario, norepinephrine and acetylcholine are the neurotransmitters, which would have been present at the higher concentrations in Sean's brain. Norepinephrine signifies to a neurotransmitter that plays an important part in dreaming, emotions, sleeping, attentiveness, and learning.
It also gets released in the bloodstream as a hormone, where it augments the rate of heart and causes the blood vessels to contract. Another neurotransmitter called acetylcholine signifies the chemical that is released by the motor neurons to instigate the muscles.
The DNA tells a ribosome how to assemble a protein.
Answer:
Active uptake (which I think you mean active transport) is important when the concentration gradient is against that of a certain substance, so it doesn't cross the membrane through diffusion or passive transport. It is sometimes necessary if a substance needs to move across a membrane but can't do so due to electrical charge or that there is a substance on the other side of the membrane preventing diffusion.
Explanation:
lemon juice is 100 times as acidic as tomato juice. remember, each step in the pH scale represents a change in concentration by a factor of 10. since tomato juice has a pH of 4.0, and lemon juice has a pH of 2.0, the concentration would change by 10 times 10.