BIOLOGY 107 MIDTERM TERMS EXAM
QUESTIONS AND ANSWERS
Polymer - Correct Answers -A long molecule consisting of many similar or identical
monomers linked together by covalent bonds.
Macromolecules - Correct Answers -A giant molecule formed by the joining of smaller
molecules, usually by a dehydration reaction. Polysaccharides, proteins, and nucleic
acids are macromolecules.
Monomer - Correct Answers -The subunit that serves as the building block of a polymer.
Enzyme - Correct Answers -A macromolecule serving as a catalyst, a chemical reagent
that increases the rate of reaction without being consumed by the reaction. Most are
proteins. A typical one can perform 1000 reactions/second (sucrose ~ 1000 rx/sec,
catalase ~ 300000 rx/sec, rubisco ~ 3 rx/sec). Most are named substrate + ase. Most
cellular processes require several of them. Are optimized for their environment (e.g.
temp, pH). Can be regulated (e.g. regulatory site which requires regulatory molecules).
Can be permanently inhibited by several toxins which mimic enzyme substrates.
Dehydration reaction - Correct Answers -A chemical reaction in which two molecules
become covalently bonded to each other with the removal of a water molecule.
Hydrolysis - Correct Answers -A chemical reaction that breaks bonds between two
molecules by the addition of water; functions in disassembly of polymers to monomers.
Carbohydrate - Correct Answers -A sugar (monosaccharide) or one of its dimers
(disaccharides) or polymers (polysaccharides).
Monosaccharide - Correct Answers -The simplest carbohydrate, active alone or serving
as a monomer for disaccharides and polysaccharides. Also known as simple sugars,
monosaccharides have molecular formulas that are generally some multiple of CH2O.
Glucose (C6H12O6) is the most common monosaccharide.
Oligosaccharide - Correct Answers -3 to 10 monosaccharides joined together.
, Disaccharide - Correct Answers -A double sugar, consisting of two monosaccharides
joined by a glycosidic linkage formed by a dehydration reaction. Functions as an energy
source and carbon source.
Polysaccharide - Correct Answers -A polymer of many monosaccharides, formed by
dehydration reactions. Made of 100s to 1000s of glucoses joined together. Glycogen
and starch are used for energy storage, and are easy to make, however they are heavy,
which makes fats and oils preferable.
Glucose (C6H12O6) - Correct Answers -Most common monosaccharide. Has two ring
structures (α and β). There are also modified ones such as NAG and NAM.
Glycogen - Correct Answers -An extensively branched glucose storage polysaccharide
found in he liver and muscle of animals; the animal equivalent of starch. Polymer of α-
glucose.
Starch - Correct Answers -A storage polysaccharide in plants, consisting entirely of
glucose monomers joined α-glycosidic linkages. Polymer of α-glucose.
Cellulose - Correct Answers -A structural polysaccharide of plant cell walls, consisting of
glucose monomers joined by β glycosidic linkages. Polymer of β-glucose.
Chitin - Correct Answers -A structural polysaccharide, consisting of amino sugar
monomers, found in many fungal (yeast) cell walls and in the exoskeletons of all
arthropods. Polymer of NAG.
Protein - Correct Answers -A biologically functional molecule consisting of one or more
polypeptides folded and coiled into a specific three-dimensional structure.
Polypeptide - Correct Answers -A polymer of many amino acids linked together by
peptide bonds.
Amino acids - Correct Answers -An organic molecule possessing both a carboxyl and
an amino group. Amino acids serve as the monomers of polypeptides.
Primary structure - Correct Answers -A linked series of amino acids with a unique
sequence.
Secondary structure - Correct Answers -Segments of the polypeptide chains in most
proteins that are repeatedly coiled or folded in patterns that contribute to the protein's
overall shape. Are the result of hydrogen bonds between the repeating constituents of
the polypeptide backbone (not the amino acid side chains)
α helix - Correct Answers -One of the main types of secondary structures, a delicate coil
held together by hydrogen bonding between every fourth amino acid.
QUESTIONS AND ANSWERS
Polymer - Correct Answers -A long molecule consisting of many similar or identical
monomers linked together by covalent bonds.
Macromolecules - Correct Answers -A giant molecule formed by the joining of smaller
molecules, usually by a dehydration reaction. Polysaccharides, proteins, and nucleic
acids are macromolecules.
Monomer - Correct Answers -The subunit that serves as the building block of a polymer.
Enzyme - Correct Answers -A macromolecule serving as a catalyst, a chemical reagent
that increases the rate of reaction without being consumed by the reaction. Most are
proteins. A typical one can perform 1000 reactions/second (sucrose ~ 1000 rx/sec,
catalase ~ 300000 rx/sec, rubisco ~ 3 rx/sec). Most are named substrate + ase. Most
cellular processes require several of them. Are optimized for their environment (e.g.
temp, pH). Can be regulated (e.g. regulatory site which requires regulatory molecules).
Can be permanently inhibited by several toxins which mimic enzyme substrates.
Dehydration reaction - Correct Answers -A chemical reaction in which two molecules
become covalently bonded to each other with the removal of a water molecule.
Hydrolysis - Correct Answers -A chemical reaction that breaks bonds between two
molecules by the addition of water; functions in disassembly of polymers to monomers.
Carbohydrate - Correct Answers -A sugar (monosaccharide) or one of its dimers
(disaccharides) or polymers (polysaccharides).
Monosaccharide - Correct Answers -The simplest carbohydrate, active alone or serving
as a monomer for disaccharides and polysaccharides. Also known as simple sugars,
monosaccharides have molecular formulas that are generally some multiple of CH2O.
Glucose (C6H12O6) is the most common monosaccharide.
Oligosaccharide - Correct Answers -3 to 10 monosaccharides joined together.
, Disaccharide - Correct Answers -A double sugar, consisting of two monosaccharides
joined by a glycosidic linkage formed by a dehydration reaction. Functions as an energy
source and carbon source.
Polysaccharide - Correct Answers -A polymer of many monosaccharides, formed by
dehydration reactions. Made of 100s to 1000s of glucoses joined together. Glycogen
and starch are used for energy storage, and are easy to make, however they are heavy,
which makes fats and oils preferable.
Glucose (C6H12O6) - Correct Answers -Most common monosaccharide. Has two ring
structures (α and β). There are also modified ones such as NAG and NAM.
Glycogen - Correct Answers -An extensively branched glucose storage polysaccharide
found in he liver and muscle of animals; the animal equivalent of starch. Polymer of α-
glucose.
Starch - Correct Answers -A storage polysaccharide in plants, consisting entirely of
glucose monomers joined α-glycosidic linkages. Polymer of α-glucose.
Cellulose - Correct Answers -A structural polysaccharide of plant cell walls, consisting of
glucose monomers joined by β glycosidic linkages. Polymer of β-glucose.
Chitin - Correct Answers -A structural polysaccharide, consisting of amino sugar
monomers, found in many fungal (yeast) cell walls and in the exoskeletons of all
arthropods. Polymer of NAG.
Protein - Correct Answers -A biologically functional molecule consisting of one or more
polypeptides folded and coiled into a specific three-dimensional structure.
Polypeptide - Correct Answers -A polymer of many amino acids linked together by
peptide bonds.
Amino acids - Correct Answers -An organic molecule possessing both a carboxyl and
an amino group. Amino acids serve as the monomers of polypeptides.
Primary structure - Correct Answers -A linked series of amino acids with a unique
sequence.
Secondary structure - Correct Answers -Segments of the polypeptide chains in most
proteins that are repeatedly coiled or folded in patterns that contribute to the protein's
overall shape. Are the result of hydrogen bonds between the repeating constituents of
the polypeptide backbone (not the amino acid side chains)
α helix - Correct Answers -One of the main types of secondary structures, a delicate coil
held together by hydrogen bonding between every fourth amino acid.
