Which of these is an example of a chemical change? a. dissolving salt in water b. melting ice c. burning a piece of wood d. breaking a tree branch

What did the first language sound like

If the coding part of an mrna molecule is 1800 nucleotides (bases) in length, this molecule will contain codons and code for a polypeptide that is amino acids long.

When you run, you begin to breathe heavier and faster. your heart beats more quickly, bringing more oxygen to your cells. which organ systems are working together here?