Old Test 4 Questions Flashcards
True or false? To facilitate the vasodilation pathway, the direct target of viagra ( the pharmaceutical used for erectile dysfunction) is cGMP phosphodiesterase.
A) true
B) false, because viagra does not directly target cGMP phosphodiesterase
C) false, because viagra does not facilitate vasodilation
True
Which cytoskeletal elements enables locomotion in crawling cells?
A) intermediate filaments
B) microtubules
C) microfilaments
D) microvilli
E) monotopic proteins
C) microfilaments
All of the following are activated in an insulin-stimulated cell except …
A) AKT kinase
B) PI3 kinase
C) GLUT
D) glycogen phosphorylase
E) all of the above are activated in response to insulin stimulation
D) glycogen phosphorylase
True or false ? Heterotrophs must take in carbon-containing molecules in the organic form, which can be used directly as both an energy source and a carbon source . They cannot synthesize organic molecules de novo.
True
Which type of diabetes is a result of an autoimmune disorder that destroys the insulin -producing cells? Select all that apply
Type I
Type II
Type III
Gestational Diabetes
Type I
What is the highest level of protein structure found in an activated receptor tyrosine kinase protein ?
Protein
Secondary
Tertiary
Quarternary
Hexonary
Quarternary
True or False? Hydrogen bonding is possible between the R groups of lysine and asparagine.
True
False
True
After a signaling molecule binds to a GPLR, the G protein…..select all that apply
Binds to IP3
binds to Ca2+ to become activated
Dissociates into two subunits
Hydrolyze GDP
Undergoes a conformational change
Dissociates into two subunits ; Undergoes a conformational change
Which of the following properties are shared myosins, kinesins, and dyneins? Select all that apply
Bind to microtubules
Are involved in forming the cell cortex
Possess ATPase activity
Individual proteins can move back and forth along the cytoskeletal element
Can move towards the positive end of the element
Are types of proteins
Possess ATPase activity ; Are types of proteins
True or false? Adipose tissue is considered a special type of neural tissue
True
False
False
Considering the epithelial layer of the Fallopian tubes, which of the following structures is (are) involved in propelling an egg cell through the fallopian tubes from the ovary towards the uterus
A) flagella
B) cilia
C) microfilaments
D) all of the above
E) both B and C
B) cilia
True or false? An inhibitor of phospholipase C could be used to block the release Ca2+ from the smooth endoplasmic reticulum
True
True or false ? In an animal cell, microtubules,but not microfilaments , are organized by the centrosome.
True
A hydropathy analysis was done on a CADM4, cell adhesion protein localized to the plasma membrane (PM) in xenopus laevis ( the African clawed frog). The CADM4 protein has an internal start transfer sequence as it’s first signaling sequence. A positive index on the plot indicates hydrophobicity, while a negative value indicates a hydrophilic region.
True or false? When localized to the PM, the N-terminus of the CADM4 protein will extend into the cytoplasm, while the C-terminus will reside within the extracellular space
True
True or false? The post-translational import pathway would be used to properly localize a selectin protein
False
Regarding a given microtubule, if the critical concentration of the plus end is 0.2 uM and the critical concentration of the minus end is 0.5 uM, what would happen if the free subunit concentration was 0.1uM?
A) the plus end would lengthen and the minus end would shorten
B) both ends would shorten
C) both ends would grow
D) nothing would happen to either end
E) none of the above
B) both ends would shorten
Which of the following sequences is correct regarding the events involved in the locomotion of crawling cells?
A) protrusion at the cell’s leading edge, attachment of protrusion, pulling the cell forward, release and retraction of trailing edge
B) attachment of protrusion, pulling the cell forward, protrusion at the cell’s leading edge, release and retraction of trailing edge
C) release and retraction of protrusion, protrusion at the cell’s leading edge, attachment of trailing edge, pulling the cell forward
D) attachment of protrusion, protrusion at the cell’s leading edge, pulling the cell forward, release and retraction of trailing edge
E) protrusion at the leading edge, pulling the cell forward, release and retraction of protrusion, attachment of trailing edge
A) protrusion at the cell’s leading edge, attachment of protrusion, pulling the cell forward, release and retraction of trailing edge
The synthesis of ATP by oxidative phosphorylation is based on several lines of evidence. Which of the following statements regarding experimental observations does not support the oxidative phosphorylation model?
A) artificial proton gradients established by the addition of an acid can drive ATP synthesis in the absence of electron transport
B) uncoupling agents that abolish the proton gradient have no affect on ATP synthesis
C) oxidative phosphorylation requires a membrane enclosed compartment
D) the proton gradient established by electron transport has enough energy to drive ATP synthesis
E) electron transport causes acidification of the intermembrane space
B) uncoupling agents that abolish the proton gradient have no affect on ATP synthesis
True or false? An actively growing end of a microtubule is rich in GDP- association tubulin
False
True or false? A primary messenger (I.e a ligand) does NOT need to enter the cell for a signal transduction cascade to be initiated within that cell
True
Which of the following statements applies to all 3 classes of cytoskeletal elements ? Select all that apply
A) they have intrinsic structural polarity
B) they assemble from polypeptide subunits
C) their constituent proteins are tissue-specific
D) they are involved in cell motility
E) the assembled element is a multimeric protein complex
B) they assemble from polypeptide subunits
E) the assembled element is a multimeric protein complex
During endocytosis, which type of motor protein would be involved in transport of a vesicle between the plasma membrane and the Golgi ?
A) myosins
B) kinesins
C) dyneins
D) tau proteins
E) selectins
C) dyneins
True or false? The minus end of a microtubule has a lower critical concentration compared to the plus end
False
The term “dynamic instability “ describes the ability of :
A) cell adhesion proteins to activate or deactivate microtubule assembly / disassembly
B) a microtubule to switch back and forth between a positive and negative charge
C) the cell cortex to rearrange during cell crawling
D) inhibitors to prevent microtubule polymerization/depolymerization
E) microtubles to switch back and forth between polymerization and depolymerization
E) microtubles to switch back and forth between polymerization and depolymerization
Reduction in which of the following metabolic pathways would help alleviate Type II diabetes?
A) glycosylation
B) glycogenesis
C) glycogenolysis
D) glycolysis
E) none of the above
C) glycogenolysis
Assuming a metastasized cancer cell can express the same types of cell adhesion proteins as a white blood cell, which type of adhesion protein would the cancer cell need to express in order to become immobilized inside a blood vessel, just prior to it exiting the blood vessel?
A) glycoproteins
B) I-CAMs
C) integrins
D) L-selectins
E) P-selectins
F) both B and C
C) integrins
Which of the following statements correctly describes the intermediate filaments (IFs?) select all that apply
A) the main role of IFs is to help the cell to withstand mechanical stress
B) they are the only cytoskeletal elements that are NOT composed of protein
C) IFs contribute to the formation of the extracellular Mateus
D) IFs are used to form the cell cortex
E) the cytoplasmic IFs are tissue-specific
A) the main role of IFs is to help the cell to withstand mechanical stress
E) the cytoplasmic IFs are tissue-specific
Insulin signaling is an example of what type of signaling?
A) synaptic
B) endocrine
C) paracrine
D) cell-to-cell contact
E) fight -or-flight
B) endocrine
Phosphoglucomutase catalyzes the inter conversion between glucose-1-phosphate (G-1-P) and glucose-6-phosphate (G-6-P) in the cell.
True or false ? Increasing levels of G-6-P in the cytoplasm would indicate the energy needs of the cell are MET, thus initiating glycogenesis
True
CAMs, cadherins, selectins and integrins are all types of cell adhesion proteins. Such proteins share all the following characteristics EXCEPT
A) they have a cytoplasmic domain that directly or indirectly interacts with cytoskeletal elements
B) they are involved in cell adhesion
C) they have an extracellular domain involved in adhesion to neighboring cells through other adhesion molecules and/or ECM components
D) they are integral membrane proteins
E) all of the above are true
E) all of the above are true
True or false? Red blood cells will lyse when placed in pure water
True
Proper embryonic symmetry is established by the movement of embryonic fluid around the developing embryo. Which of the following cell structures are involved in generating the fluid movement ?
A) intermediate filaments
B) myosins
C) microfilaments
D) nodal cilia
E) embryonic flagella
F) more than one above is possible
D) nodal cilia
Skipping a meal and not eating for a while will stimulate the secretion of which molecule into the blood?
A) glycogen synthase
B) insulin
C) Ca+2
D) glycogen
E) glucagon
E) glucagon
Kinesin is a motor molecule that is characterized by
A) motion toward the “plus” end of the microtubule
B) motion along actin filaments
C) sliding along actin in cilia
D) motion of axon email structures
E) both A and D
A) motion toward the “plus” end of the microtubule
During odor detection, ac signal transduction cascade is initiated that results in the opening of s channel protein localized to the plasma-membrane . This channel is involved in the transport of Ca2+. By which mechanism will Ca2+ move through the channel protein when the channel protein is open?
A) into the cell by osmosis
B) out of the cell by active transport
C) into the cell by active transport
D)into the cell by facilitated diffusion
E) out of the cell by facilitated diffusion
D)into the cell by facilitated diffusion
When trying to identify the cellular origins of a metastasized tumor, which protein would be a useful indicator to distinguish between different cell types?
A) actin
B) cytokeratins
C) nuclear lamin A
D) tubulin
E) any of the above
B) cytokeratins
True or false? When blood glucose levels are low, insulin is secreted by pancreatic beta cells
True
False, beta cell do not secret insulin
False, beta cells do not secret insulin when blood glucose levels are low
False, beta cells do not secret insulin when blood glucose levels are low
Which of the following is(are) True of the Cori cycle? Select all that apply
Muscle cells are under anaerobic conditions when the Cori cycle occurs
Glycogenolysis in the liver occurs to release free glucose
Lactate is converted into glucose in the liver
ATP is produced in the liver for use in muscle cells
Gluconeogenesis
Muscle cells are under anaerobic conditions when the Cori cycle occurs; Lactate is converted into glucose in the liver
True or false ? Cilia are constructed from microfilaments. Flagella are contracted from microtubles
True
False, because cilia are constructed from microtubles, while flagella are constructed from microfilaments
False because both are constructed to from microfilaments
False because both are constructed from microtubles
False because both are constructed from microtubles
Shown below is a GCPR. A GCPR is a type of …..membrane protein
Peripheral
Multi-subunit integral
Monotopic integral
Mutipass integral
Single pass integral
Mutipass integral
Regarding the GCPR shown below, to generate the observed topology across the plasma membrane, the first signal sequence encountered within the primary structure of the GCPR protein had to be an…. transfer sequence
A) N-terminal stop
B) N-terminal start
C) internal stop
D) internal start
E) C-terminal start
B) N-terminal start
What will happen as a result of insulin binding to an insulin receptor on the plasma membrane of a given cell? (GLUT = glucose transporter)
A) glycogenesis is negatively regulated; GLUT is inserted in the PM to facilitate the uptake of glucose into the cell
B) glycogenesis is negatively regulated; GLUT is removed from the PM to prevent uptake of glucose into the cell
C) glycogenesis is positively regulated ; GLUT is removed from the PM to prevent uptake of glucose into their cell
D) glycogenesis is positively active regulated; GLUT is inserted in the PM to facilitate the uptake glucose into the cell
E) glycogenesis is positively regulated; GLUT is inserted in the PM to facilitate the removal of glucose from the cell
D) glycogenesis is positively active regulated; GLUT is inserted in the PM to facilitate the uptake glucose into the cell
True or false ? Even if a cell lacked the ability to synthesize GTP, it would still be able to respond to epinephrine
False
The microtubule organizing center (MTOC) is responsible for determining the location of which neural process during cell differentiation in a neuron?
A) axon
B) cell body
C) dendrite
D) neurofibrillary tangle
E) tau
A) axon
Each of the following is an intracellular messenger involved in propagating a signal except
A) cAMP
B) Ca2+
C) insulin
D) IP3
E) all of the above are intracellular messengers
C) insulin
Using radioactive XFF, you reset to see if the properties of the receptor are more similar to the receptor for epinephrine or estrogen. If the receptor is more similar to the epinephrine receptor, you would expect to find the radioactivity
A) within the cytoplasm of the cell
B) on the surface of the cell
C) within the nucleus of the cell
D) could be A or B
B) on the surface of the cell
Which adhesion molecules will be expressed by the leukocyte to allow the leukocyte to roll along the endothelial cell layer. Select all that apply
A) cohesions
B) glycolipids
C) ICAMs
D) integrins
C) selectins
C) selectins
Which of the following pertain to cAMP? Select all that apply
A) is inhibited by cAMP phosphodiesterase
B) is produced by protein kinase A
C) is part of the signal transduction cascade resulting in vasodilation
D) is a type of secondary messenger
E) is part of the flight or fight signal transduction cascade
A) is inhibited by cAMP phosphodiesterase
D) is a type of secondary messenger
E) is part of the flight or fight signal transduction cascade
PKA targeTs phosphorylase kinase. The action of PKA on phosphorylase kinase then leads to the ….of the ….pathway
A) deactivation ; glycogenesis
B) deactivation ; glycogenolysis
C) activation; glycogenesis
D) activation ; glycogenolysis
E) both A and D
D) activation ; glycogenolysis
Which of the following statements describes NADH? Select all that apply
A) it can accept electrons for use in oxidative phosphorylation
B) it has more chemical energy that NAD+
C) it is the oxidized form of NAD+
D) it accepts electrons from pyruvate during fermentation
E) it is less electronegative compared to oxygen
B) it has more chemical energy that NAD+
E) it is less electronegative compared to oxygen
Which of the following is a main function of microfilaments?
A) to provide tracks for guiding intracellular transport
B) to enable cells to undergo locomotion
C) to enable cells to withstand the mechanical stress that occurs when cells are stretched
D) to organize cytoplasmic contents
E) to increase surface area through the formation of microvilli
B) to enable cells to undergo locomotion
True or false? To facilitate the vasodilation pathway the direct target of viagra is nitric oxidize synthase
True
False because viagra does not directly target nitric oxide synthase
False because viagra does not facilitate vasodilation
False because viagra does not directly target nitric oxide synthase
True or false? The highest level of protein structure found in an activated receptor tyrosine kinase protein is tertiary structure
False
After a signaling molecule binds to a GPCR, the associated G protein… select all the apply
A) cleaves PIP2 into DAG and IP3
B) binds to Ca2+ to become activated
C) dissociates into 3 subunits
D) replaces GDP with GTP
E) undergoes a conformational change
D) replaces GDP with GTP
E) undergoes a conformational change
True or false ? Adipose tissue is considered a special type of muscle tissue
False
True or false ? The cotranslational import pathway would be used to properly localize a selectin protein
True
Considering the epithelial layers of the trachea, which of the following structures are involved in propelling mucus across the epithelial layer to prevent debris and microorganisms from entering the lungs. Select all that apply
A) flagella
B) cilia
C) microtubles
D) myosins
D) intermediate filaments
B) cilia
C) microtubles
True or false? An inhibitor from phospholipase C could be used to block the release of cAMP from the smooth endoplasmic reticulum
False
True or false ? In animal cell, both microtubles and microfilaments are organized by the centrosome
False
True or false ? An actively growing end of a microtubule is rich in GTP - associated tubulin
True
ATP is produced in the mitochondria by a process called oxidative phosphorylation. A similar process, called photophosphorylation, occurs in the chloroplast. Which statement regarding ATP production is CORRECT ?
A) During BOTH oxidative phosphorylation and photophosphorylation, electrons are transferred from the electron transport chain to ATP synthase to drive ATP production
B) during oxidative phosphorylation, but NOT photophosphorylation, electrons are transferred from the electron transport chain to ATP synthase to drive ATP production in the mitochondria
C) during photophosphorylation, but not oxidative phosphorylation, electrons dare transferred from the electron transport chain to ATP synthase to drive ATP production in the chloroplast
D) electrons are NOT transported to ATP synthase in either oxidative phosphorylation or photophosphorylation
D) electrons are NOT transported to ATP synthase in either oxidative phosphorylation or photophosphorylation
Disulfide bonds stabilize the…structure of a protein and can be broken by …conditions
A) secondary; reducing
B) tertiary ; oxidizing
C) tertiary; reducing
D) secondary; oxidizing
E) primary ; reducing
C) tertiary; reducing
Which of the following is not classified as a type of connective tissue ?
A) blood
B) bone
C) tendons
D) nervous
E) fat
D) nervous
If liver cells are homogeneated, then the membrane components are separated from the cytoplasmic fraction, adding epinephrine to the isolated cytoplasmic fraction will cause…
A) cAMP to be produced
B) calcium ions to be released
C) G-proteins to be activated
D) All of the above
E) none of the above as the epinephrine receptors are localized in the PM
E) none of the above as the epinephrine receptors are localized in the PM
True or false? If a cell produced an analog of GTP that could not be hydrolyzed to GDP, the microtubules inside this cell would undergo depolymerization
True
As electrons move through the electron transport chain, protons are pumped into the …resulting in an…. In the pH of the matrix
A) inter membrane space; decrease
B) matrix, decrease
C) matrix; increase
D) inter membrane space; increase
E) none of the above
D) inter membrane space; increase
Which of the following are involved in propelling substances across cell surfaces ?
A) flagella
B) cilia
C) myosins
D) microfilaments
E) more than one of the above
B) cilia
Which of the following is the most heterogeneous type of cytoskeletal element in terms of their molecular composition?
A) microtubles
B) microfilaments
C) myosins
D) cytoplasmic intermediate filaments
E) nuclear intermediate filaments
D) cytoplasmic intermediate filaments
An inhibitor of which of the following could be use to block the release of a Ca+2 from the smooth endoplasmic reticulum ?
A) adenylyl Cyclase
B) phospholipase C
C) calmodulin
D) phosphodiesterase
E) none of the above, Ca2+ is not released from the smooth ER
B) phospholipase C
True or false? If a cell lacked the ability to synthesize GTP, it would not be able to respond to epinephrine
True
All of the following are secondary messengers involved in relaying a signal transduction event EXCEPT
A) epinephrine
B) inositol triphosphate
C) Ca 2+
D) cAMP
E) all of the above are secondary messengers
A) epinephrine
Pastoris is species of yeast which uses methanol as both a carbon and energy source and be therefore classified as
A) chemoautotrophs
B) chemheterotrophs
C) photoautotrophs
D) photo heterotrophs
B) chemheterotrophs
One of the major categories of receptors in the plasma membrane reacts by forming dimers, adding phosphate groups, and then activating relay proteins. Which type does this ?
A) G proteins
B) steroid receptors
C) G protein linked receptors (GPLR)
D) IP3 receptors
E) receptor of tyrosine kinases
E) receptor of tyrosine kinases
Hydrolysis of GTP to GDP on microtubles
A) provides energy meant of axoneme
B) drives the movement of MT associated motor proteins
C) leads to MT depolymerization if the rate of hydrolysis outpaces the rate of polymerization
D) is necessary for polymerization of MT subunits
E) more than one above
C) leads to MT depolymerization if the rate of hydrolysis outpaces the rate of polymerization
Signal transduction involved three basic steps….
Reception,transduction, cellular response
G proteins
A) are active when GTP is bound
B) can activate themselves by cleaving GTP to form GDP
C) are active in their trimeric forms
D) are a type of receptor protein involved in signal transduction
E) enzymatically catalyze the formation of cAMP
A) are active when GTP is bound
Regarding GLUT and glycogen synthase, how would a liver cell respond as a result of insulin binding to an insulin receptor on the plasma membrane ?
A) GLUT is removed from the PM to prevent uptake of glucose into the cell; GS is activated
B) GLUT is inserted in the PM to facilitate the uptake of glucose into the cell; GS is deactivated
C) GLUT is removed from the PM to prevent uptake of glucose into the cell; GS is deactivated
D) GLUT is inserted in the PM to facilitate the uptake of glucose into the cell; GS is activated
D) GLUT is inserted in the PM to facilitate the uptake of glucose into the cell; GS is activated
