Exam 2: A: The Chemical Basis of Life

Chemistry can be defined as the science that deals with the structure,arrangement,and composition of substances and the reactions they undergo.

A type of chemical reaction called hydrolysis is an example of an anabolic reaction.

Hydrogen bonds form as a result of the attraction between polar molecules.

Litmus paper will turn red in the presence of a base.

Electrolytes are characterized by having either a positive or a negative charge.

High-density lipoprotein (HDL)is also called the "bad" cholesterol.

The three most common disaccharides-sucrose,lactose,and maltose-each contain at least one molecule of glucose.

The digestion of food is an example of a synthesis reaction.

Steroids are often called tissue hormones.

Metabolism includes the processes of both anabolism and catabolism.

A neutral atom that has 22 protons could have 25 neutrons.

Acids are electrolytes that produce OH⁺ ions.

The atomic mass of an atom is equal to the number of protons plus the number of neutrons.

As the hydrogen ion concentration increases,the pH value increases.

RNA never exists in a double-stranded form.

A solution with a pH of 3 has 100 times more hydrogen ions than a solution with a pH of 5.

Adenine and thymine are referred to as purine bases,which are important constituents of a DNA molecule.

Amino acids get their name because they have an amino group (NH₃⁺)and an acid group (COO-).

The number and arrangement of electrons orbiting in an atom's outer shell determine its chemical activity.

Trace elements in the body make up about 1% of the body weight.