Electrophoresis Blood Quiz Questions
- 1.
While synthesizing a new blue pigment, a chemist noticesthat the new compound congregates between an aqueous(water) environment and a hydrophobic environment.When added to a mixture of oil and water, the pigmentcreates a blue ring around the droplets of oil. Which of thefollowing statements best describes this new pigment?
- A.
The pigment is amphipathic, having polar and nonpolar regions.
- B.
The pigment is probably hydrophobic and is attempting to bond with the oil.
- C.
The pigment is hydrophilic and will not form hydrophobic bonds with the oil.
- D.
The pigment is a polar molecule and is forming hydrogen bonds with both the water and oil molecules.
- E.
The pigment is neither polar or nonpolar, but is apolar.
Correct Answer
A. The pigment is amphipathic, having polar and nonpolar regions.Explanation
The correct answer is that the pigment is amphipathic, having polar and nonpolar regions. This is because the pigment is able to congregate between an aqueous environment (water) and a hydrophobic environment (oil). The presence of both polar and nonpolar regions allows the pigment to interact with both the water and oil molecules, resulting in the formation of a blue ring around the droplets of oil.Rate this question:
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- 2.
An enzyme synthesized in the laboratory is found to havelittle activity when compared to the same enzyme extractedfrom cell culture. Both enzymes were examined and haveidentical amino acid composition. What is the bestexplanation for the lack of activity of the synthesizedenzyme?
- A.
The synthetic enzyme was not made of amino acids
- B.
Denaturation of the synthesized enzyme was not complete.
- C.
The synthesized enzyme was not folded correctly
- D.
The van der Waals radius was altered during laboratory synthesis.
- E.
The ATP required for self-assembly was present in the cell extract but not in the laboratory synthesis.
Correct Answer
C. The synthesized enzyme was not folded correctlyExplanation
The lack of activity of the synthesized enzyme can be best explained by the fact that it was not folded correctly. Folding is a crucial process for enzymes to achieve their functional conformation and catalytic activity. If the enzyme does not fold correctly, it may result in misaligned active sites or improper interactions with substrates, leading to a decrease in activity. Despite having identical amino acid composition, the synthetic enzyme might have encountered difficulties in achieving the proper folding that is essential for its functionality.Rate this question:
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- 3.
Why is the decrease in the surface area/volume ratio as cellsincrease in size a problem for cells?
- A.
The ability of a cell to obtain a sufficient amount of nutrients from the environment is hampered
- B.
The ability of a cell to get rid of wastes at a high enough rate is compromised by the lower ratio.
- C.
The ability of a cell to get rid of nutrients to the environment is hampered
- D.
The ability of a cell to build up wastes at a high enough rate is compromised by the lower ratio.
- E.
A and b
Correct Answer
E. A and bExplanation
As cells increase in size, their surface area/volume ratio decreases. This is a problem for cells because it hampers their ability to obtain a sufficient amount of nutrients from the environment. With a lower ratio, the cell has less surface area available for nutrient absorption. Additionally, the decrease in surface area/volume ratio compromises the cell's ability to get rid of wastes at a high enough rate. This is because the smaller surface area makes it more difficult for wastes to be expelled from the cell efficiently. Therefore, both options a and b are correct explanations for why the decrease in surface area/volume ratio is problematic for cells.Rate this question:
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- 4.
Membrane proteins may function in
- A.
Temperature control.
- B.
Information storage
- C.
Amphipathic modification
- D.
Protein manufacture.
- E.
Receiving extracellular signals.
Correct Answer
E. Receiving extracellular signals.Explanation
Membrane proteins are embedded in the cell membrane and play a crucial role in receiving signals from the external environment. These proteins act as receptors and transmit information from outside the cell to the inside, initiating various cellular responses. This allows cells to respond and adapt to changes in their surroundings, including extracellular signals such as hormones, neurotransmitters, and growth factors. Therefore, membrane proteins primarily function in receiving extracellular signals.Rate this question:
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- 5.
Disulfide bonds are often found to stabilize which of thefollowing levels of protein structure?
- A.
Secondary
- B.
Primary
- C.
Tertiary
- D.
All of the above
- E.
None of the above
Correct Answer
C. TertiaryExplanation
Disulfide bonds are often found to stabilize the tertiary level of protein structure. Tertiary structure refers to the three-dimensional folding of a protein, which is crucial for its proper functioning. Disulfide bonds form between two cysteine residues, creating a covalent bond that helps to maintain the protein's overall structure and stability. These bonds can occur within a single polypeptide chain or between different chains, contributing to the folding and stability of the protein in its native conformation. Therefore, disulfide bonds play a significant role in stabilizing the tertiary structure of proteins.Rate this question:
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- 6.
Which of the following is NOT true of phospholipids?
- A.
Serine is a molecule that may be part of a phosphoglyceride.
- B.
Phospholipids are important in membrane structure.
- C.
Phosphatidic acid contains two fatty acids and a phosphate group.
- D.
Sphingolipids are the predominant phospholipid in membranes.
- E.
Phospholipids are amphipathic.
Correct Answer
D. Sphingolipids are the predominant phospholipid in membranes.Explanation
Sphingolipids are not the predominant phospholipid in membranes.Rate this question:
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- 7.
The term amphoteric describes the characteristic of somemolecules that have ________.
- A.
Only a single polar region
- B.
Two polar regions
- C.
Can donate or accept electrons
- D.
Can accept or donate protons
- E.
Both a polar and a nonpolar region
Correct Answer
D. Can accept or donate protonsExplanation
Amphoteric molecules have the ability to both accept and donate protons. This means that they can act as both an acid (donate protons) and a base (accept protons) depending on the reaction conditions. This characteristic is important in various chemical reactions and allows these molecules to participate in a wide range of chemical processes.Rate this question:
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- 8.
Which of the following is NOT a function of membranes?
- A.
Define cell boundaries
- B.
Regulation of transport
- C.
Compartmentalization
- D.
Cell-cell communication
- E.
Information storage
Correct Answer
E. Information storageExplanation
The correct answer is "information storage" because membranes primarily function to define cell boundaries, regulate transport, compartmentalize cellular components, and facilitate cell-cell communication. Membranes are primarily composed of lipids and proteins that form a selectively permeable barrier, allowing the cell to control the movement of molecules in and out. They also help in organizing cellular structures and organelles, enabling specialized functions within different compartments. Additionally, membranes contain various receptors and signaling molecules that facilitate communication between cells. However, information storage is not a primary function of membranes, as genetic information is stored in the form of DNA within the cell nucleus.Rate this question:
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- 9.
HCompounds that react with free hydrogen or hydroxyl ions,thereby resisting changes in pH, _______.
- A.
Are called buffers
- B.
Protect cells and organisms from fluctuations in salinity
- C.
Protect cells and organisms from pH stability
- D.
A and b
- E.
A and c
Correct Answer
A. Are called buffersExplanation
Compounds that react with free hydrogen or hydroxyl ions, thereby resisting changes in pH, are called buffers. Buffers are important in maintaining the pH stability of a solution or environment. They can absorb excess hydrogen ions (acidic conditions) or release hydrogen ions (basic conditions) to maintain a relatively constant pH. Buffers play a crucial role in protecting cells and organisms from fluctuations in pH, which could be harmful to their biochemical processes. Therefore, the correct answer is "are called buffers."Rate this question:
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- 10.
With respect to the outer and inner faces of the lipid bilayerof the cell membrane, the composition of lipids is
- A.
A mirror image
- B.
Asymmetrical.
- C.
Not identical, but symmetrical.
- D.
Highly random and varies throughout the cell.
- E.
Identical.
Correct Answer
B. Asymmetrical.Explanation
The composition of lipids in the outer and inner faces of the lipid bilayer of the cell membrane is asymmetrical. This means that the types and quantities of lipids differ between the two faces of the bilayer. The outer face may contain more glycolipids and sphingomyelin, while the inner face may have more phosphatidylserine and phosphatidylethanolamine. This asymmetry is important for various cellular processes, including membrane trafficking, cell signaling, and membrane fusion.Rate this question:
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- 11.
Which of the following is NOT a fundamental property ofcarbon? 1
- A.
Carbon-containing molecules form stereoisomers.
- B.
Carbon-containing molecules are stable.
- C.
Carbon-containing molecules are diverse.
- D.
Carbon atoms are most likely to form ionic bonds with one another.
- E.
Carbon has a valence of 4.
Correct Answer
D. Carbon atoms are most likely to form ionic bonds with one another.Explanation
Carbon atoms are most likely to form covalent bonds with one another, not ionic bonds. Ionic bonds involve the transfer of electrons between atoms with opposite charges, while covalent bonds involve the sharing of electrons between atoms. Since carbon atoms have four valence electrons, they are able to share electrons with other carbon atoms, forming stable covalent bonds.Rate this question:
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- 12.
Why is a selectively permeable membrane so important toliving things?
- A.
The membrane may absorb several times its weight in cholesterol.
- B.
It provides a good barrier between the inside and outside of the cell.
- C.
It allows cells to attach to adjacent tissues.
- D.
Proteins will avoid a selectively permeable membrane.
- E.
All of the above
Correct Answer
B. It provides a good barrier between the inside and outside of the cell.Explanation
A selectively permeable membrane is important to living things because it provides a good barrier between the inside and outside of the cell. This barrier allows the cell to control the movement of substances in and out of the cell, ensuring that only necessary molecules are allowed to enter or exit. This regulation is crucial for maintaining the cell's internal environment and carrying out essential cellular processes.Rate this question:
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- 13.
An organism is isolated from a glacier, where it has beenobserved to be thriving. Based on your knowledge of theplasma membrane, you would expect to find apredominance of
- A.
Equal amounts of saturated and unsaturated fatty acids, as long as the chain was close to 12 carbons in length.
- B.
Largely saturated fatty acids.
- C.
Cell wall to define the cell, as the cell membrane would not be present.
- D.
Largely unsaturated fatty acids.
- E.
None of the above
Correct Answer
D. Largely unsaturated fatty acids.Explanation
In a glacier environment, where temperatures are extremely low, the plasma membrane of an organism needs to be flexible and fluid to function properly. Unsaturated fatty acids have double bonds in their carbon chains, which introduce kinks and prevent the fatty acids from packing tightly together. This results in a more fluid and flexible plasma membrane, making it easier for the organism to survive in the cold conditions. Therefore, it is expected to find a predominance of largely unsaturated fatty acids in the plasma membrane of the organism isolated from the glacier.Rate this question:
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- 14.
Based on your knowledge of the chemistry of the cellmembrane, which of the following compounds would youcouple with a new drug in order to achieve better uptake bycells?
- A.
Several mannose-6-phosphate monomers
- B.
Carbohydrates
- C.
Any hydrophilic substance
- D.
Polar amino acids
- E.
Lipids
Correct Answer
E. LipidsExplanation
Lipids would be the best compound to couple with a new drug in order to achieve better uptake by cells. Lipids are a major component of cell membranes and have hydrophobic properties, which allow them to easily pass through the hydrophobic interior of the cell membrane. By coupling the drug with lipids, it can be effectively transported across the cell membrane and into the cells, enhancing its uptake and potential efficacy.Rate this question:
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- 15.
Cholesterol
- A.
Destabilizes the cell membrane.
- B.
Is found only in plants.
- C.
Intercalates between the fatty acid chain within the bilayer.
- D.
Is found in abundance in prokaryotic cell membranes.
- E.
Hincreases permeability for small cations.
Correct Answer
C. Intercalates between the fatty acid chain within the bilayer.Explanation
Cholesterol is a molecule that is found in the cell membrane of animals. It is able to intercalate, or insert itself, between the fatty acid chains within the bilayer of the cell membrane. This intercalation helps to stabilize the cell membrane and maintain its fluidity and integrity. By inserting itself between the fatty acid chains, cholesterol can prevent them from packing too closely together, which would make the membrane too rigid. This allows the cell membrane to remain flexible and functional.Rate this question:
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- 16.
Based on the following amino acid sequence, whichregion(s) is/are hydrophobic?1[Lysine-Lysine-Glutamine] - 2[Alanine-Glycine-Tryptophan-Valine] - 3[Tyrosine-Cysteine-Serine-Arginine] - 4[Histidine-Glutamic acid-Cysteine-Tryptophane]
- A.
Region 1
- B.
Region 3
- C.
Region 2
- D.
Region 4
Correct Answer
C. Region 2Explanation
Region 2 is hydrophobic because it contains the amino acids Alanine, Glycine, Tryptophan, and Valine. These amino acids have nonpolar side chains, which are hydrophobic in nature and tend to avoid water.Rate this question:
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- 17.
With respect to the outer and inner faces of the lipid bilayerof the cell membrane, the composition of proteins is
- A.
Asymmetrical.
- B.
Identical.
- C.
Not identical, but symmetrical.
- D.
A mirror image.
- E.
Highly random and varies throughout the cell.
Correct Answer
A. Asymmetrical.Explanation
The composition of proteins in the lipid bilayer of the cell membrane is described as asymmetrical. This means that the proteins are not evenly distributed or identical on the outer and inner faces of the bilayer. Instead, they are arranged in a non-symmetrical manner, with different types and amounts of proteins present on each side. This asymmetry is important for various cellular processes, such as cell signaling and membrane transport, as it allows for specific protein functions to occur on each side of the bilayer.Rate this question:
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- 18.
The technique that allows various proteins to bedifferentiated based on size, once the proteins have beendenatured, is
- A.
Ferritin conjugated lectins.
- B.
SDS-PAGE.
- C.
Photobleaching.
- D.
Liposome formation.
- E.
The freeze fracture technique.
Correct Answer
B. SDS-PAGE.Explanation
SDS-PAGE is a technique commonly used in molecular biology and biochemistry to separate proteins based on their size. In this technique, proteins are denatured and coated with sodium dodecyl sulfate (SDS) which gives them a uniform negative charge. The proteins are then loaded onto a polyacrylamide gel and subjected to an electric field. Since the gel has pores of different sizes, smaller proteins migrate faster through the gel while larger proteins migrate slower. This separation based on size allows for the differentiation of proteins, making SDS-PAGE the correct answer in this case.Rate this question:
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- 19.
Which amino acid is most likely to be found in the core ofa protein?
- A.
Phenylalanine
- B.
Asparagine
- C.
Serine
- D.
Threonine
- E.
Glutamic acid
Correct Answer
A. PhenylalanineExplanation
Phenylalanine is most likely to be found in the core of a protein because it is a nonpolar amino acid with a bulky aromatic side chain. Nonpolar amino acids tend to be found in the hydrophobic core of proteins, away from water, while polar amino acids like asparagine, serine, threonine, and glutamic acid are more likely to be found on the surface of the protein where they can interact with water molecules.Rate this question:
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- 20.
Chaperones were first identified as_______________proteins and they informationfor protein folding. They ______________ interactions tooccur
- A.
Heat-shock, do. Hydrophobic
- B.
Heat- shock, do. Hydrophilic
- C.
Heat shock, do not. Hydrophilic
- D.
Heat shock, do not. Hydrophobic
Correct Answer
D. Heat shock, do not. HydrophobicExplanation
Chaperones were first identified as heat shock proteins and they do not require hydrophobic interactions to occur. Heat shock proteins are a class of chaperones that are produced in response to cellular stress, such as high temperatures. They assist in protein folding and prevent the aggregation of misfolded proteins. While hydrophobic interactions can play a role in protein folding, chaperones do not rely on these interactions for their function. Instead, they use other mechanisms, such as binding to exposed hydrophobic regions, to assist in protein folding.Rate this question:
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- 21.
The á-helix is characterized by orientation of ______ themolecular axis.
- A.
H bonds perpendicular to
- B.
Ionic bonds parallel to
- C.
Ionic bonds perpendicular to
- D.
Peptide bonds perpendicular to
- E.
H bonds parallel to
Correct Answer
E. H bonds parallel toExplanation
The α-helix is a common secondary structure in proteins, characterized by a right-handed coil. It is stabilized by hydrogen bonds formed between the carbonyl oxygen of one amino acid and the amide hydrogen of an amino acid four residues ahead. These hydrogen bonds run parallel to the molecular axis of the helix, contributing to its stability and structure.Rate this question:
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- 22.
What level of structure in proteins is held together byintramolecular R group interactions?
- A.
Primary structure
- B.
Secondary structure
- C.
Tertiary structure
- D.
Quaternary structure
- E.
C and d
Correct Answer
C. Tertiary structureExplanation
The tertiary structure of proteins is held together by intramolecular R group interactions. This refers to the three-dimensional arrangement of the protein molecule, which is stabilized by bonds and interactions between the R groups of amino acids. These interactions can include hydrogen bonding, hydrophobic interactions, disulfide bonds, and electrostatic interactions. The tertiary structure is crucial for the overall folding and function of the protein.Rate this question:
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- 23.
What kind of protein is associated with either theextracellular or cytoplasmic surface using a lipid tail?
- A.
Integral membrane proteins
- B.
Peripheral proteins
- C.
GPI-anchor proteins
- D.
Chaperones
Correct Answer
C. GPI-anchor proteinsExplanation
GPI-anchor proteins are a type of protein that are associated with either the extracellular or cytoplasmic surface using a lipid tail. These proteins have a glycosylphosphatidylinositol (GPI) anchor attached to their C-terminus, which allows them to be embedded in the lipid bilayer of the cell membrane. This anchor helps to anchor the protein to the membrane and allows it to function in various cellular processes, such as cell signaling and cell adhesion. Therefore, GPI-anchor proteins are the correct answer to the question.Rate this question:
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- 24.
What kind of proteins can be obtained by treating cells withhigh-salt solutions?
- A.
GPI-peripheral proteins
- B.
Peripheral proteins
- C.
Transmembrane proteins
- D.
A and c
- E.
B and c
Correct Answer
B. Peripheral proteinsExplanation
Treating cells with high-salt solutions can result in the extraction of peripheral proteins. Peripheral proteins are proteins that are loosely attached to the cell membrane and can be easily removed or extracted without disrupting the lipid bilayer. High-salt solutions disrupt the ionic interactions between the peripheral proteins and the cell membrane, allowing them to be extracted. This is why peripheral proteins can be obtained by treating cells with high-salt solutions.Rate this question:
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- 25.
While culturing some cells, you lower the temperature ofthe culture. What happens immediately to the membranefluidity?
- A.
Nothing happens
- B.
The membrane becomes more fluid
- C.
The membrane becomes less fulid
- D.
The membrane fluidity fluctuates back and forth from high to low fluidity
- E.
The membrane fluidity fluctuates back and forth from low to high
Correct Answer
C. The membrane becomes less fulidExplanation
Lowering the temperature of the culture causes the membrane to become less fluid. This is because at lower temperatures, the phospholipids in the membrane move less and become more tightly packed together, resulting in a decrease in fluidity.Rate this question:
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- 26.
What word below characterizes the amino acids that arefound in an á-helical segment that spans a membrane?
- A.
Amphipathic
- B.
Idiopathic
- C.
Hydrophilic
- D.
Hydrophobic
Correct Answer(s)
C. Hydrophilic
D. HydrophobicExplanation
The word "Hydrophilic" characterizes the amino acids that are found in an α-helical segment that spans a membrane. Hydrophilic amino acids are attracted to water and are typically found on the outer surface of a protein, interacting with the aqueous environment. On the other hand, "Hydrophobic" amino acids are repelled by water and are commonly found in the interior of a protein, away from the aqueous environment. Therefore, both hydrophilic and hydrophobic amino acids play a crucial role in stabilizing the α-helical structure within the membrane.Rate this question:
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- 27.
Where are hydrophobic interactions most likely to occur?
- A.
On the surface of a water-soluble protein
- B.
The core of a water-soluble protein
- C.
In contact with water molecules
- D.
Between two charged molecules
- E.
Between two ions
Correct Answer
B. The core of a water-soluble proteinExplanation
Hydrophobic interactions are nonpolar interactions between hydrophobic molecules or regions that are driven by the tendency of water to exclude nonpolar substances. The core of a water-soluble protein is where hydrophobic amino acid residues are typically found, as they are repelled by water molecules and tend to cluster together to minimize their exposure to water. This allows the protein to fold into a stable, compact structure. Therefore, hydrophobic interactions are most likely to occur in the core of a water-soluble protein.Rate this question:
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- 28.
In a living organism, where are ionic bonds most likely to befound?
- A.
In the cytoplasm
- B.
Between DNA strands
- C.
Deep in a protein's core where water is excluded
- D.
On the surface of a protein
- E.
On the surface of a lipid
Correct Answer
C. Deep in a protein's core where water is excludedExplanation
Ionic bonds are formed between ions, which are atoms that have gained or lost electrons, resulting in a positive or negative charge. These bonds are strong and require the presence of opposite charges. In a living organism, ionic bonds are most likely to be found deep in a protein's core where water is excluded. Proteins are complex molecules that play critical roles in the structure and function of cells. The core of a protein is typically hydrophobic, meaning it repels water. This hydrophobic environment allows for the formation of stable ionic bonds between charged amino acid residues, contributing to the stability and structure of the protein.Rate this question:
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- 29.
Proteins are often composed of two or more distinctmodules that fold up independently of one another. Theyoften represent parts of a protein that function in a semiindependentmanner. These modules are called ______.
- A.
Dominoes
- B.
Lipid rafts
- C.
Motif
- D.
Domains
Correct Answer
D. DomainsExplanation
Proteins are composed of distinct modules called domains. These domains fold up independently and often represent parts of a protein that function semi-independently. They play a crucial role in protein structure and function, allowing proteins to have different regions with specific functions.Rate this question:
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- 30.
What level of structure in proteins is held together byintermolecular R group interactions?
- A.
Primary
- B.
Secondary
- C.
Tertiary
- D.
Quaternary
Correct Answer
C. TertiaryExplanation
Tertiary structure in proteins is held together by intermolecular R group interactions. This level of structure involves the folding of the protein chain into a three-dimensional shape, which is stabilized by various interactions between the side chains of amino acids. These interactions can include hydrogen bonding, hydrophobic interactions, ionic interactions, and disulfide bonds. The tertiary structure is crucial for the overall function and stability of the protein.Rate this question:
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- 31.
What property of membranes allows interactions to takeplace within the membrane, including the assembly ofmembrane protein clusters at particular sites and theformation of specialized structures?
- A.
Hydrophobicity
- B.
Hydrophilicity
- C.
Amphoteric nature
- D.
Fluidity
- E.
Amphipatic nature
Correct Answer
D. FluidityExplanation
The property of fluidity in membranes allows interactions to take place within the membrane, including the assembly of membrane protein clusters at particular sites and the formation of specialized structures. This means that the lipids and proteins in the membrane are able to move laterally and interact with each other, facilitating various cellular processes. This fluidity also allows for the dynamic rearrangement of membrane components, which is crucial for membrane function and adaptability.Rate this question:
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- 32.
What are the building blocks of a phosphoglyceride,specifically phosphatidic acid?
- A.
Glycerol + 2 phosphate groups + 1 fatty acid
- B.
Glycerol + 1 phosphate group + 2 fatty acids
- C.
Glycerol + 2 phosphate groups
- D.
Glycerol + 3 fatty acids
- E.
Glycerol + 2 phosphate groups + 2 fatty acids
Correct Answer
B. Glycerol + 1 phosphate group + 2 fatty acidsExplanation
A phosphoglyceride, specifically phosphatidic acid, is composed of glycerol, one phosphate group, and two fatty acids. This composition allows for the molecule to have a hydrophilic head (the phosphate group) and hydrophobic tails (the fatty acids), making it ideal for forming the lipid bilayer of cell membranes.Rate this question:
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- 33.
Which of the following is not a function of peripheralproteins?
- A.
Receptors
- B.
Mechanical support for membrane
- C.
Enzymes
- D.
Molecules that serve in signal transmission
Correct Answer
A. ReceptorsExplanation
Peripheral proteins are proteins that are located on the outer surface of the cell membrane, but are not embedded within it. They play various roles in maintaining the structure and function of the cell membrane. Receptors, mechanical support for the membrane, and enzymes are all known functions of peripheral proteins. However, molecules that serve in signal transmission are not typically associated with peripheral proteins. These molecules are more commonly associated with integral proteins, which are embedded within the cell membrane.Rate this question:
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- 34.
What enzyme was instrumental in the discovery of GPIanchoredproteins? It was found that this enzyme wouldrelease certain membrane proteins from a membrane.
- A.
Phospathase
- B.
GPI-phosphorylase
- C.
Phospholipase
- D.
Trypsin
Correct Answer
C. PhospholipaseExplanation
Phospholipase is the correct answer because it is an enzyme that is known to release certain membrane proteins from a membrane. This property of phospholipase makes it instrumental in the discovery of GPI-anchored proteins, as it can cleave the glycosylphosphatidylinositol (GPI) anchor that attaches these proteins to the membrane. Therefore, phospholipase plays a crucial role in the identification and study of GPI-anchored proteins.Rate this question:
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- 35.
What directly or indirectly determines the transitiontemperature?
- A.
The ability of lipid molecules to be packed together
- B.
Whether the fatty acid chains of the lipids are saturated or unsaturated
- C.
The extent to which the fatty acid chains of the lipids contain double bonds
- D.
The length of the fatty acid chains
- E.
All of the above
Correct Answer
E. All of the aboveExplanation
All of the factors mentioned in the options directly or indirectly determine the transition temperature. The ability of lipid molecules to be packed together affects the fluidity and stability of the lipid bilayer, which in turn affects the transition temperature. The saturation or unsaturation of the fatty acid chains determines the presence of double bonds, which affects the fluidity and flexibility of the lipid bilayer. The length of the fatty acid chains also influences the packing and organization of lipids, thereby impacting the transition temperature. Therefore, all of these factors collectively determine the transition temperature.Rate this question:
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- 36.
Which proteins move the farthest during SDSpolyacrylamidegel electrophoresis?
- A.
The biggest
- B.
The smallest
- C.
The more negative
- D.
The more positive
- E.
A and c
Correct Answer
B. The smallestExplanation
During SDS polyacrylamide gel electrophoresis, proteins are separated based on their size. Smaller proteins have less mass and are able to move through the gel matrix more easily, resulting in them traveling the farthest. Therefore, the smallest proteins move the farthest during SDS polyacrylamide gel electrophoresis.Rate this question:
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