Biomolecules Questions and Answers
Biology
BiomoleculesChemical mechanisms that can turn off or reduce an enzyme are
Inhibitors
activators
centrioles
vacuoles
Biology
BiomoleculesWhen a protein is extracellular either secreted or trans-membrane, it has sugars attached to it (becoming a glycoprotein). The sugars attach mostly where?
A. residues of D or E
B. residues of S or N
C. residues of F or M
D. sphingolipids
E. none of the above
B. residues of S or N
Biology
BiomoleculesWhy are the side chains of amino acids so important?
They're not really important. All 20 amino acid is pretty similar in their properties.
They're what the digestive system removes to use as vitamins.
They're what the digestive system removes to use for energy.
They break off to function as signaling molecules.
They function as a biochemical "tool belt" which determines what the protein can do.
Biology
BiomoleculesWhich of the following is a general feature of kinases? (13% answered correctly)
A. NONE OF THESE
B. The catalyzed reaction must be protected from water
C. ALL OF THESE
D. Kinases convert aldoses to ketoses
E. Phosphoryl groups are transferred from AMP to an acceptor
Biology
BiomoleculesMalonyl-CoA is synthesized in the cytosol by the enzyme with Acetyl-CoA carboxylase. Write a balanced equation that shows the overall reaction catalyzed by this enzyme. What is the mechanistic role of the coenzyme biotin in the acetyl CoA carboxylase reaction?
Biology
BiomoleculesNeurotransmitter Shazam is made from a precursor molecule Sha by an enzyme called Zam. A new drug AntiZam inhibits the of action Zam. AntiZam is a Shazam .
agonist
protagonist
antagonist
precursor
Biology
BiomoleculesWhat blood type do you have if there is:
NO A antigen
YES B antigen
NO Rh antigen
A+
A-
B+
B-
Biology
BiomoleculesHow many ingredients from this cereal box label are sources of carbohydrates?
Ingredients: Whole grain wheat, corn bran, sugar, glycogen, honey, salt, sucralose, evaporated cane juice, high fructose syrup from corn, grape juice concentrate, calcium propionate, and soybean oil.
8
7
14
2
11
None of these is correct.
Biology
BiomoleculesDiamonds have a density of 3.51 kg/L. If you find a 0.52-Liter diamond while digging in your yard one day, what is the mass of the diamond?
Biology
BiomoleculesStructurally lipids are a very diverse group but they are all placed in one group because of what property?
They all contain four interlocking rings
They are composed of glycerol and fatty acids
They are all important chemical messengers
They are all relatively insoluble in water
Biology
Biomoleculeswhich of the following statements is true regarding starches?
a. are produced by cells of both plants and animals
b. sugar monomers are connected by beta- 1,4-glycosidic bonds
c. polymer molecule has a straight linear structure
d. are polymers composed only of glucose monomers
e. cannot be digested by animals because we lack the correct enzyme
Biology
BiomoleculesIn 1962, three scientists who contributed to the discovery of the structure of the DNA molecule were awarded the Nobel Prize in Physiology and Medicine. The fourth scientist who contributed to this discovery, Rosalind Franklin, was not awarded the prize as she had died before this honor could be bestowed. What was her major contribution to this discovery?
A She determined that DNA was a crystal.
B She captured the X-ray crystallography image that led to the discovery.
C She determined that nitrogenous bases occurred in pairs.
D She determined that DNA was a double helix.
Biology
BiomoleculesParagraph 5 discusses the importance of the discovery of the structure of the DNA molecule.
What did this discovery allow scientists to confirm?
A. Specific base pairing allowed DNA to duplicate itself.
B. If Chargaff's rule were followed, then the bonds between bases were equal.
C. Specific base pairing allowed for the transfer of genetic information.
D. All of the above
Biology
BiomoleculesFor each food listed below, choose whether it is a saturated fat or an unsaturated fat.
Cream cheese
Vegetable oil
Corn oil
Biology
BiomoleculesEnolase is an enzyme that catalyzes one reaction in glycolysis in all organisms that carry out this process. The amino acid sequence of enolase is similar but not identical in the organisms. Researchers purified enolase from Saccharomyces cerevisiae, a single-celled eukaryotic yeast that grows best at 37°C, and from Chloroflexus aurantiacus, a bacterium that grows best at the much higher temperature of 55°C. The researchers compared the activity of purified enolase from the two organisms by measuring the rate of the reaction in the presence of varying concentrations of substrate and a constant amount of each enzyme at both 37°C and 55°C.
a. Depending on the organism, the optimal pH for enolase to catalyze its reaction is between 6.5 and 8.0. Describe how a pH below or above this range is likely to affect enolase and its catalytic ability. b. Identify the appropriate negative control the researchers most likely used when measuring the reaction rate in the presence of each organism's enolase.
c.The researchers predict that for any particular concentration of substrate, the C. aurantiacus enolase-catalyzed reaction is more rapid at 55°C than at 37°C. Provide reasoning to justify the researchers' prediction.
Biology
BiomoleculesWhat is the purpose of the RNA primer in DNA replication?
provide nucleotides with an exposed 3 end
recruits histone deacetylation proteins
establishes the correct translational reading frame
synthesizes the leading strand in pieces
attaches a modified guanine on the 5 end
Biology
BiomoleculesThe building of complex organic molecules from simpler ones is called...
Anabolism
photosynthesis
Oxidation
Fermentation
Catabolism
Biology
BiomoleculesWhich of the following statements is CORRECT?
Thymine normally pairs with Cytosine in double-stranded DNA
Monosaccharides are the monomer subunit of polypeptides
Carbohydrates, proteins, and nucleic acids are polymers
Aspartic acid is an example of a non-polar amino acid
Unsaturated fats do not have double bonds in the carbon chain
Biology
BiomoleculesWhat is the definition of an anabolic metabolic pathway?
A pathway that releases energy and stores matter
A pathway that releases energy and releases matter
A pathway that stores energy and stores matter
A pathway that stores energy and releases matter
Biology
BiomoleculesWhat are the major differences between DNA andRNA in eukaryotic cells? Select the three (3) best
answers.
DNA is a true nucleic acid, RNA is not
DNA stores information about proteins, RNA also stores information about proteins, but also plays other roles in translation
DNA is an information storing molecule, RNA acts as an enzyme
The sugars in the nucleotides of DNA are different than those of RNA
DNA is a more stable molecule, RNA does not last as long in the cell
DNA is processed before it leaves the nucleus, RNA remains in the nucleus
Biology
BiomoleculesIf each round gray molecule shown above represents an nucleic acid molecule, then the large molecule made of all of them linked together must be a macromolecule.
Protein
Lipid
Carbohydrate
Nucleic acid
Biology
BiomoleculesIf each round gray molecule shown above represents an amino acid molecule, then the large molecule made of all of them linked together must be a ... macromolecule.
Protein
Lipid
Carbohydrate
Nucleic acid
Biology
BiomoleculesAccording to the Brønsted-Lowry definition,
a base is a proton donor
a base produces H+ ions in aqueous solutions
an acid acts as the solvent
an acid is a proton acceptor
a base is a proton acceptor
Biology
BiomoleculesThe active site of an enzyme
includes the entire enzyme
increases the energy of reaction
is remote from the site of substrate attachment
is the region where the reaction takes place
is converted to a product
Biology
BiomoleculesAn increase in the temperature of a solution usually
decreases the solubility of a solid solute in the solution
increases the solubility of a gas in the solution
increases the solubility of a solid solute in the solution
decreases the solubility of a liquid solute in the solution
increases the boiling point
Biology
BiomoleculesA biologist working in a lab adds a compound to a solution that contains an enzyme and substrate. This compound binds to the enzyme and increases the rate at which the enzyme converts substrate to product. This increase in enzyme activity persists even if the concentration of substrate in the reaction changes. Therefore, which of the following is TRUE of the compound?
the compound is an allosteric activator
the compound binds to the active site of the enzyme
the compound is a catalyst for the reaction
the compound is an allosteric inhibitor
Biology
BiomoleculesWhen liquid silver nitrate and liquid sodium chloride are combined, solid silver chloride forms along with a new liquid, sodium nitrate. Which substance represents the precipitate?
Osilver nitrate
O silver chloride
Osodium chloride
O sodium nitrate
Biology
BiomoleculesWhich of the following is not a true statement related to healthy food choices that lead to weight loss?
O It is necessary to avoid foods that contain fat in order to lose
weight.
O It is necessary to increase the intake of nutrient-dense foods in
order to reduce weight.
O Healthy eating requires a person to pay attention to hunger
and satiety cues.
O Healthy eating requires people to consume nutritious foods in
moderate quantities.
Biology
BiomoleculesWhich of the following is not a part of the male reproductive system?
A.greater vestibular glands (Bartholin's glands)
B. epididymis
C.bulbourethral gland (Cowper's gland)
D.prostate gland
Biology
BiomoleculesCatabolic reactions are coupled with ATP ____, whereas anabolic reactions are coupled with ATP ____.
synthesis; hydrolysis
hydrolysis; synthesis
amphibolism; repression
deamination; beta oxidation
Biology
BiomoleculesWhich of the following does not reflect anabolism?
Beta oxidation of fatty acids to acetyl CoA.
Enzyme production from amino acids.
DNA replication from nucleotides.
Fatty acid assimilation to form lipids.
Biology
BiomoleculesEnzymes are ....
broken down in reactions that require energy input
proteins that function as catalysts
used up in chemical reactions
not needed for catabolic reactions
All of the choices are correct.
Biology
BiomoleculesFeedback inhibition, a negative feedback mechanism that regulates enzymes, is best
described as
substrate binding to DNA, blocking enzyme transcription
product binding to DNA, blocking enzyme transcription
substrate binding to enzyme in noncompetitive site
product binding to enzyme in noncompetitive site
None of the choices are correct.
Biology
BiomoleculesDuring which phase of cellular respiration is the majority of ATP formed?
Krebs cycle
Glycolysis
Processing of pyruvic acid for the Krebs cycle
Electron transport
All phasesproduce the same number of ATP molecules.
Biology
BiomoleculesGleevec is a chemotherapy drug used to treat cancer. What is the mechanism by which Gleevec blocks Abl kinase enzyme action?
Gleevec reduces the ATP level in the body and starves the Abl enzyme
Gleevec purifies cancer cells and returns them to a normal functioning state
Binding of Gleevec to the active site locks Abl in an inactive conformation
Binding of Gleevec to the active site mutates threonine 315 to methionine
Gleevec is a protease that cleaves the Abl protein at the regulatory spine
Biology
BiomoleculesA drug binds to the active site of an enzyme. If it is bound to the active site of the enzyme, it prevents substrate binding. This drug would be considered a(n)
noncompetitive inhibitor.
allosteric inhibitor.
allosteric activator.
competitive inhibitor.
Biology
BiomoleculesA student was asked to create a model to explain how a mutation that occurs during DNA replication will be inherited
Where would the mutation need to be located in the model to guarantee it is passed down to offspring?
The mutation is found in the somatic cells of one of the parents.
The mutation is found on the Y chromosome of the father.
The mutation is found on one X chromosome of the mother.
The mutation is found in the gametes of one of the parents.
Biology
BiomoleculesIn your experiment, you may not have seen a significant difference between ethanol, propanol and butanol in the time to lyse the cells.
Pick the most likely reason for this from the list below.
Watching the lysing of the erythrocytes by eye is much too sensitive and gives rise to errors.
Watching the lysing of the erythrocytes by eye may not be sensitive enough to differentiate between lysis times when alcohols are added.
Some of the alcohols had gone off and therefore did not act as predicted.
The blood we used (horse blood) is fundamentally different to human blood and so the transport of alcohols across the membrane will be different.
Biology
BiomoleculesA cell membrane has a double layer of molecules. These molecules are made up of a
phosphorus-containing "head" and two long, fatty acid "tails. "Which of the following best
explains why the molecules are classified as lipids?
a. They contain phosphorus.
b. They form a double layer.
c. They are made up of fatty acids.
d. They are found in the cell membrane.
Biology
BiomoleculesChoose the antimicrobial category that is most selectively toxic.
Antimicrobials that inhibit cell wall synthesis
Antimicrobials that inhibit protein synthesis
Antimicrobials that interfere with nucleic acid structure and function
Antimicrobials that inhibit folic acid synthesis
Antimicrobials that interfere with cell membrane structure and function
Biology
BiomoleculesBased on the knowledge that cleavage is characteristic of crystals, which of the following
gems would not have this property?
A. ruby
B. emerald
C. pearl
D. diamond
E. sapphire
Biology
BiomoleculesWhat do the odds ratios demonstrate? The disease is strongly associated with...
Smokers at the senior center who had indirect contact with recruits
Direct contact with recruits at the high school, but not at the senior center
Direct contact with recruits at the spior center, but not at the high school
Non-12th graders at the high school
Biology
BiomoleculesMatch the each carbohydrate listed withe the appropriate classification.
Polysaccharide
Monosaccharide
Disaccharide
Biology
BiomoleculesHydrogen peroxide is a substance that is produced as a byproduct of many cell processes. However, hydrogen peroxide is toxic to cells. In fact, if cells are unable to break down hydrogen peroxide, they become poisoned and die.
The chemical reaction for the breakdown of hydrogen peroxide is shown below.
2 H₂O ⇒ 2 H₂O + O₂
What role does catalase play in this reaction?
A. Catalase is an enzyme that speeds up the reaction.
B. Catalase is a reactant that gets used up in the reaction.
C. Catalase in an enzyme that slows down the reaction.
D. Catalase is a product that is created during the reaction.
Biology
BiomoleculesHeat is useful in the destruction of bacteria because heat...
denatures enzymes by altering their 3D protein structures
prevents the production of folic acid in the cell
depresses the uptake of minerals of bacteria
depresses ATP synthesis
All of the above
Biology
BiomoleculesA non-competitive inhibition can be overcome by...
C. increasing the temperature
E. None of the above
A. increasing the concentration of substrate
D. increasing the amount of coenzyme
B. increasing the concentration of product
Biology
Biomolecules3. The active site is...
A. a region in a cofactor that interacts with a particular enzyme
D. a region of an enzyme to which the product of a reaction binds
B. a region of an enzyme to which non-competitive inhibitors bind
C. a region of an enzyme to which the substrate of a reaction binds
E. All of the above
Biology
BiomoleculesWhat are Bohr protons and how do they relate to different mechanisms involved in the Bohr effect?
Biology
Biomolecules15. Origins of replication are the
a. sites where DNA transcription starts.
b. binding sites for the protein complex that initiates DNA synthesis.
c. loops with two replication forks seen in replicating DNA
d. forks where DNA replication is occurring.