Bio Chapter 5
Glucose
Which of the following is NOT a polymer?
A peptide bond
A glycosidic linkage is analogous to which of the following in proteins?
Have a glycerol backbone
Phospholipids and triglycerides both
Leucine would be in the interior, and serine would be on the exterior of the globular protein.
The R-group, or side chain, of the amino acid serine is -CH2-OH. The R-group, or side chain, of the amino acid leucine is -CH2-CH-(CH3)2. Where would you expect to find these amino acids in a globular protein in aqueous solution?
Lipids
Which of these classes of biological molecules does NOT include polymers?
Monosaccharide
A molecule with the chemical formula C6H12O6 is probably a
Frogs than humans
A new organism is discovered in the forests of Costa Rica. Scientists there determine that the polypeptide sequence of hemoglobin from the new organism has 72 amino acid differences from humans, 65 differences from a gibbon, 49 differences from a rat, and 5 differences from a frog. These data suggest that the new organism is more closely related to
Cholesterol
All of the following contain amino acids EXCEPT
Always alter the primary structure of the protein, sometimes alter the tertiary structure of the protein, and sometimes affect its biological activity
Changing a single amino acid in a protein consisting of 325 amino acids would
Do not have a polar or charged region
Cooking oil and gasoline (a hydrocarbon) are not amphipathic molecules because they
The polar heads interact with water; the nonpolar tails do not.
How do phospholipids interact with water molecules?
10
How many molecules of water are used to completely hydrolyze a polymer that is 11 monomers long?
RNA
If 14C-labeled uracil is added to the growth medium of cells, what macromolecules will be labeled?
40
If a DNA sample were composed of 10% thymine, what would be the percentage of guanine?
5'TGCAAT3'
If one strand of a DNA molecule has the sequence of bases 5'ATTGCA3', the other complementary strand would have the sequence
As a disaccharide
Lactose, a sugar in milk, is composed of one glucose molecule joined by a glycosidic linkage to one galactose molecule. How is lactose classified?
Are insoluble in water
Lipids
Alzheimer's and Parkinson's only
Misfolding of polypeptides is a serious problem in cells. Which of the following diseases are associated with an accumulation of misfolded polypeptides?
Function in the synthesis of proteins
One of the primary functions of RNA molecules is to
Tertiary
Rhodopsins are light-sensitive molecules composed of a protein (opsin) and retinal (derivative of vitamin A). Opsin is a membrane protein with several α-helical segments that loop back and forth through the plasma membrane. There are two classes of rhodopsins. According to Oded Beje, one class has relatively slow dynamics (a photocycle of approximately 0.5 second) and is well suited for light detection. The second class has faster dynamics (a photocycle of approximately 0.02 seconds) and is well suited for chemiosmosis: pumping of protons or chloride ions across cell membranes. Oded Beje was the first, in September 2000, to report on a rhodopsin (proteorhodopsin) found in the domain Bacteria. [SOURCE: O. Beje et al., Science 289 (2000): 1902.] Proteorhodopsin consists of a single polypeptide chain. What is the highest level of structure found in this protein?
Are polymers of glucose
Starch and cellulose
Is solid at room temperature
The label on a container of margarine lists "hydrogenated vegetable oil" as the major ingredient. Hydrogenated vegetable oil
C18H32O16
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?
The components of the R-group
What component of amino acid structure varies among different amino acids?
Cellulose
What does the term insoluble fiber refer to on food packages?
The position of the carbonyl group
What is the difference between an aldose sugar and a ketose sugar?
The amount of branching that occurs in the molecule
What is the major structural difference between starch and glycogen?
Dehydration reactions assemble polymers; hydrolysis reactions break polymers apart.
Which of the following best summarizes the relationship between dehydration reactions and hydrolysis?
A nitrogenous base, a phosphate group, and a sugar
Which of the following descriptions best fits the class of molecules known as nucleotides?
Vegetable oil has more double bonds than animal fats.
Which of the following is the best explanation for why vegetable oil is a liquid at room temperature while animal fats are solid?
Denatured (unfolded) proteins do not function normally.
Which of the following is the strongest evidence that protein structure and function are correlated?
The 5' end has a phosphate group attached to the number 5 carbon of ribose.
Which of the following statements about the 5' end of a polynucleotide strand of RNA is correct?
DNA nucleotides contain a different sugar than RNA nucleotides
Which of the following statements best summarizes the differences between DNA and RNA?
A phosphorus atom, P
Which one of the following is NOT a component of each monomer used to make proteins?
Chitin
Which polysaccharide is an important component in the structure of many animals and fungi?
Primary structure
You disrupt all hydrogen bonds in a protein. What level of structure will be preserved?
Cysteine
You have just sequenced a new protein found in mice and observe that sulfur-containing cysteine residues occur at regular intervals. What is the significance of this finding?
