A sample that contains an organic molecule has the following constituents: carbon, hydrogen, oxygen, nitrogen, and phosphorus. Is the molecule more likely to be a carbohydrate, a lipid, a protein, or a nucleic acid?

An atom of the element calcium has 20 protons and 20 neutrons. Determine the following information about calcium:

(a) Number of electrons

(b) Atomic number

(c) Atomic weight

(d) Number of electrons in each energy level

A certain reaction pathway consists of four steps. How would decreasing the amount of enzyme that catalyzes the second step affect the amount of product produced at the end of the pathway?

An important buffer system in the human body involves carbon dioxide (CO₂) and bicarbonate ion (HCO₃^-) in the reversible reaction

CO₂ + H₂O ⇌ H₂CO₃ ⇌ H⁺ + HCO₃^-

If a person becomes excited and exhales large amounts of CO₂, how will the pH of the person's body be affected?