AP Bio Unit 1 Test
How many peptide bonds are present in a polypeptide that contains 45 amino acids?
44
How many molecules of water are needed to completely hydrolyze a polysaccharide that is 10 monomers long
9
The molecular formula for glucose is C6H12O6. What would be the molecular formula for a molecule made by linking three glucose molecules together by dehydration reactions?
C18H32O16
What is the difference between covalent bonds and ionic bonds?
Covalent bonds involve the sharing of electrons between atoms; ionic bonds involve the electrical attraction between atoms.
Which of the following is true of cellulose?
It is a primary structural component of plant cell walls.
Why are hydrocarbons insoluble in water?
The majority of their bonds are nonpolar covalent carbon-to-hydrogen linkages.
DNase is an enzyme that catalyzes the hydrolysis of the covalent bonds that join nucleotides together. What would first happen to DNA molecules treated with DNase?
The phosphodiester bonds between deoxyribose sugars would be broken.
Which of the following is true of both starch and cellulose?
They are both polymers of glucose.
Which of the following statements concerning saturated fats is true?
They are generally solid at room temperature
Which of the following statements regarding lipids is true?
They are insoluble in water.
Which of the following statements regarding saturated fatty acids is true?
They are the principal molecules in lard and butter.
A nucleotide is composed o
a nitrogenous base, a phosphate group, and a pentose sugar.
Large organic molecules are generally synthesized by polymerization of a few types of simple subunits. Which of the following is an exception to this statement?
a steroid
Changing a single amino acid in a protein consisting of 433 amino acids would
always alter the primary structure of the protein and sometimes alter its tertiary structure or function.
Which of the following is a monomer used to build a biological polymer?
amino acid
Which of the following is a correct monomer/polymer pairing?
amino acid/polypeptide
If cells are grown in a medium containing radioactive 15N, which of these molecules will be labeled?
both proteins and nucleic acids
Which two functional groups are always found in amino acids?
carboxyl and amino
On food packages, to what does the term insoluble fiber refer?
cellulose
What is a common chemical reaction mechanism by which cells make polymers from monomers?
dehydration reactions
Which of the following chemical equations describes a hydrolysis reaction?
disaccharide + H2O monosaccharide + monosaccharide
In an aqueous solution, water molecules associate with one another through which of the following? a. hydrophobic interaction
hydrogen bonds
What maintains the secondary structure of a protein?
hydrogen bonds between the amino group of one peptide bond and the carboxyl group of another peptide bond
Which of the following molecules lacks amino acids?
insulin
If cells are grown in a medium containing radioactive 32P, which of these molecules will be radioactively labeled?
nucleic acids
In a normal cellular protein, where would you expect to find a hydrophilic amino acid such as asparagine
on the exterior surface of the protein, interacting with water
A covalent bond is likely to be polar when
one of the atoms sharing electrons is much more electronegative than the other atom.
Which bonds are created during the formation of the primary structure of a protein?
peptide bonds
Which bonds maintain the primary structure of a protein
peptide bonds
Which of the following large biological molecules will self-assemble into a bilayer when mixed with water? Selected:
phospholipids
If cells are grown in a medium containing radioactive 35S, which of these molecules will be radioactively labeled?
proteins
Interactions between the side chains (R groups) in a polypeptide are most important in stabilizing which of the following?
tertiary structure
A nutritional supplement developed for athletes is shown to contain only carbon, hydrogen, and oxygen. Based on these data, you may safely conclude that
the food may contain carbohydrates and lipids, but not protein.
The chemical behavior of an atom depends primarily upon which of the following?
the number of electrons in the valence shell
Which of the following is an example of a dehydration reaction?
the reaction of two monosaccharides, forming a disaccharide with the release of water
The biochemical reaction that joins two amino acids to form a dipeptide is accompanied by
the release of a water molecule.
Lactase is an enzyme composed of a single polypeptide that hydrolyzes the disaccharide lactose to produce monosaccharides. The optimal pH for lactase activity is 6. Transfer of lactase to pH 5 results in a substantial decrease in enzyme activity, likely due to the disruption of
the secondary and tertiary structure of the enzyme.
Which of the following compounds are formed by dehydration reactions?
triacylglycerols