Answer:
C. Protein
Explanation:
Proteins contain C, H, O, and N.
Most notably, they contain an R group (aka a side chain), which is different for each for amino acid. The R group is symbolized by the letter R in the image.
A chemical substance that can be formed from the ionic bonding of an anion and a cation would be Al2O3.
Explanation:
The best-known neurotransmitters responsible for such fast, but short-lived excitatory action are acetylcholine, norepinephrine, and epinephrine while GABA is the major inhibitory neurotransmitter. Neurons are the basic building blocks of the nervous system.
Answer:
In the African savanna, more wildebeests are born than the environment can support. Which is most likely to happen over a period of years as a result? Individuals that are well suited to the environment reproduce, and those that have lesser adaptations die before they reproduce.