When two or more atoms or reactants bond to form a new, more complex structure, the reaction is called (a)
Normal pH of human blood averages:
If a solution has a pH of 6.0, this means that
|A)||the concentration of hydrogen ions is higher than the concentration of hydroxide ions|
|B)||the pH is alkaline|
|C)||the hydroxide ion concentration is high|
|D)||there are 10 times more hydroxide ions in this solution than in a solution with a pH of 7.0|
If a patient’s blood pH moves from 7.42 to 7.7, which of the following is true?
|A)||The patient has a condition called alkalosis.|
|B)||The patient has a condition called acidosis.|
|C)||A small change in pH reflects a small change in hydrogen ion concentration.|
|D)||The blood pH is still within a normal range.|
Which of the following substances is most acidic?
|A)||cow’s milk - pH 6.6|
|B)||apple juice - pH 3.0|
|C)||cabbage - pH 5.3|
|D)||distilled water - pH 7.0|
Choose the correct statement regarding organic compounds.
|A)||They all contain carbon, nitrogen, and hydrogen.|
|B)||Many dissolve in water but do not release ions.|
|C)||Water and carbon dioxide are examples of organic compounds.|
|D)||Organic compounds are typically found outside, not inside, cells.|
The inorganic substance(s) most directly involved in muscle contraction and conduction of nerve impulses is(are)
|D)||sodium and potassium ions|
Which of the following inorganic substances is a metabolic waste product?
Most of the energy needed by cells is supplied by
Plant starch consists of long chains of
Lipids include all of the substances below except
A fat that has all of its carbon atoms joined by single carbon-to-carbon bonds is said to be
How do phospholipids differ from fats?
|A)||Phosphorus atoms are substituted for carbon atoms.|
|B)||Phospholipids have no glycerol portion.|
|C)||Phospholipids have a phosphate group in place of the third fatty acid.|
|D)||Phospholipids have a phosphate group attached to each fatty acid chain.|
The function of a protein is determined by its
Choose the true statement regarding steroids.
|A)||The steroid cholesterol is stored only in limited areas of the body.|
|B)||Steroids have a hydrophilic and a hydrophobic portion.|
|C)||Steroids consist of long, straight chains of carbon atoms.|
|D)||The sex hormones estrogen and testosterone are steroids.|
Which of the following is not a function of proteins?
|A)||control of the speed of chemical reactions|
|B)||combine with carbohydrates to form receptors on cell surfaces|
|C)||serve as structural materials|
|D)||provide insulation to conserve heat|
Which of the following elements is found in proteins and nucleic acids but not other organic compounds?
The type of chemical bond that contributes the most to maintaining the three-dimensional shape of a protein is a(n)
When hydrogen bonds within a protein break, the protein is said to be
The shape of a protein is determined by
|A)||the nucleic acids that comprise the protein|
|B)||the function that the protein has in the body|
|C)||the sizes of amino acids in the protein|
|D)||the genes that encode the sequence of the protein’s amino acids|
Too much or too little of certain chemicals can cause diseases.
If the shape of a protein changes too much, its ability to function will be impaired
Mass and weight are technically not the same concept.
As the concentration of hydrogen ions increases relative to hydroxide ions, pH will rise.
The atomic weight of an atom is determined by the sum of its protons and electrons.
The protons carry a positive electrical charge and electrons carry a negative electrical charge.
A sodium ion has a positive charge because it has gained an electron to fill its outer shell.
DNA contains deoxyribose and is a double-stranded polynucleotide.
One pair of shared electrons forms a single covalent bond; two pairs of shared electrons forms a double covalent bond.
A molecular formula depicts how atoms are joined and arranged in molecules.
Synthesis requires energy and is important to the growth of body parts.
A catalyst affects the speed with which a chemical reaction takes place, but it is not consumed by the reaction.
Electrolytes that release hydrogen ions in water are called bases.
Triglycerides do not dissolve in water because they lack a polar region and are therefore hydrophilic.