Cell Bio exam 2
If you were looking within a cell for organized clathrin structures, you would find them associated with which of the following structures? a. lysomes b. trans Golgi complex c. endoplasmic reticulum d. inner membrane of mitochondria e. extracellular matrix
Answer b. trans Golgi complex
True or False: Alcohol is a by product of fermentation by yeast?
Answer: True
True or False: Once vesicle budding occurs , clathrin molecules are released from the vesicle ?
Answer: True
During receptor mediated endocytosis, the ultimate fate of the vesicle and /or its contents include(s): a. transcytosis b. transport endosome for digestion c. recycling of receptors d. only choices B and C E. choices A,B, and C
Answer E. choices A,B, and C
The endoplasmic reticulum is a site for a. N-linked glycosylation of polypeptides b. drug detoxification by catalase c. potassium storage in muscle cells d. addition of lipid residues e. both choices B and C
Answer a. N-linked glycosylation of polypeptides
Which of the following occur in the ER lumen regarding proteins? a. fold b. form disulfide bonds c. are "decorated" with oligosaccharide chains d. all of them
Answer d. all of them
Which of the following organelles is associated with the ability to catabolize alkanes found in oil and petroleum products? a. Golgi b. endoplasmic reticulum c. lysosomes d. peroxisomes. e. all of the above
Answer d. peroxisomes
Bacterial proteins were radioactively labeled and fed to phagocytosis cells. The protein that will ultimately be secreted from a the cell. If all is functioning well, in which order (from first to last) do you expect to the find the protein in the cell until it is secreted? a. rER=>secretory vesicle=>Golgi=>environment b. rER=>Golgi=>sER=>nucleus=>environment c. nucleus=> rER=>Golgi=>secretory vessicle=> environment d. sER=>Golgi=>secretory vesicle=> environment e. rER=>Golgi=>secretory vesicle=> environment
Answer e. rER=>Golgi=>secretory vesicle=> environment
Which of the following statements about secretion is true? (a)The membrane of a secretory vesicle will fuse with plasma mbr when it discharges its contents to the cell's exterior. (b) Vesicles for regulated exocytosis will not bud off the trans Golgi network until the appropriate signal has been received from the cell. (c) The signal sequences of proteins destined for constitutive exocytosis ensure their packaging into the correct vesicles. (d) Proteins destined for constitutive exocytosis aggregate as a result of the acidic pH of the trans Golgi network.
Answer (a)The membrane of a secretory vesicle will fuse with plasma mbr when it discharges its contents to the cell's exterior.
True or False: Electrons gain energy as they move through the electron transport chain?
Answer : False: b/c they actually lose energy going through ETC
Which of the following molecules stabilizes the cell membrane during coated pit formation? A) mannose-6-phosphate B) KDEL signals C) clatherin D) botulinum toxin E) stabilin
Answer: A) mannose-6-phosphate
Which of the following is associated with extracellular digestion via release of the contents of lysosomes directly to the environment? A) fertilization of animal eggs B) rheumatoid arthritis C) autophagy D) only choices A and B E) choices A, B, and C
Answer: D) only choices A and B
Most proteins destined to enter the endoplasmic reticulum (a)are transported across the membrane after their synthesis is complete. (b)are synthesized on free ribosomes in the cytosol. (c)begin to cross the membrane while still being synthesized (d)remain within the endoplasmic reticulum.
Answer: (c)begin to cross the membrane while still being synthesized
A protein that is N-glycosylated is expected to A) be secreted from the cell. B) be localized in the endoplasmic reticulum. C) be localized in the Golgi body. D) eventually become an endosome
Answer: A) be secreted from the cell.
The organelle of plant cells that is analogous to the lysosome in animal cells is the A) vacuole. B) triskelion. C) microsome. D) endosome. E) lysosome.
Answer: A) vacuole.
All of the following are part of the core oligosaccharide side chain in the ER, except A) N-acetyl glucosamine. B) erythrose. C) mannose. D) glucose. E) both choices A and C
Answer: B) erythrose
Oxidation of very long fatty acids occurs in the A) mitochondria. B) peroxisomes. C) lysosomes. D) smooth endoplasmic reticulum.
Answer: B) peroxisomes.
A protein is destined to be secreted from a cell, in which of the following organelle would you expect to find the protein first? A. Endosome b. Golgi apparatus c. Lysosome d. Secretory vesicle
Answer: B. Golgi apparatus
The continuous released of mucus by the epithelial cells lining the respiratory tract is an example of A) regulated secretion. B) constitutive secretion. C) the mucus response. D) the formation of clathrin-coated pits.
Answer: B. constitutive secretion.
You want to engineer a yeast cell to manufacture and secrete a bacterial protein product. To do this properly, you need to make certain that a. plenty of clathrin- coated pits may be formed b. the appropriate signal sequence is present c. the yeast cell is capable of phagocytosis d. mannose-6-phosphate is added to the protein e. all of the above
Answer: B. the appropriate signal sequence is present
Regulatory secretion of hormones would be associated with ________ at the transface of the Golgi. A) endosomes B) lysosomes C) clathrin-coated vesicles D) non-clathrin vesicles E) microsomes
Answer: C) clathrin-coated vesicles
When bacterial proteins radioactively labeled are fed to phagocytic cells. The proteins within the phagocytic cell became increasingly more radioactive over time. This observation is the result of the activity of A) mitochondria. B) chloroplasts. C) lysosomes. D) peroxisomes. E) the Golgi apparatus.
Answer: C) lysosomes
Which organelle will use up oxygen and give off carbon dioxide and water? A.lysosomes B.Golgi C.mitochondria D.chloroplasts E.ER
Answer: C. mitochondria
In plants, chloroplasts are necessary for: A.respiration. B.secretion. C.photosynthesis. D.storage. E.movement
Answer: C. photosynthesis
Mitochondria are/synthezised: a. structures involved in the breakdown of ATP b. organelles involved in the synthesis of proteins C) synthesize proteins for use outside the cell D) involved in producing ATP for cellular energy
Answer: D) involved in producing ATP for cellular energy
The "powerhouse" of the cell is the: A.chloroplast. B.Golgi apparatus. C.ribosome. D.mitochondria.
Answer: D. mitochondria
The endosymbiotic hypothesis argues that prokaryotes became some of the organelles of early eukaryotic cells. This would be supported by what evidence? A. vacuoles can "come and go" across the plasma membrane. B.mitochondria and chloroplasts have their own DNA. C.Mitochondria and chloroplasts are nearly identical to some free living prokaryotes. D.mitochondria and chloroplasts have their own DNA AND are nearly identical to some free living prokaryotes.
Answer: D.mitochondria and chloroplasts have their own DNA AND are nearly identical to some free living prokaryotes.
Both plant and animal cells have mitochondria because they both: A.have photosynthesis B.have a large vacuole. C.have ER D.need ATP for energy
Answer: D.need ATP for energy
Lysosomal storage diseases are the result of deficiencies in lysosomal proteins. An example of one such disorder A) adult-onset diabetes. B) tuberculosis. C) Huntington's disease. D) chronic fatigue syndrome. E) Tay-Sachs disease.
Answer: E) Tay-Sachs disease.
Which of these is best associated with plant cells? A.cilia/flagella B.chloroplasts/centrioles C.round shape D.small vesicles E.chloroplast/cell wall
Answer: E.chloroplast/cell wall
Which organelle will give off oxygen and use up carbon dioxide? A.Golgi B.rough ER C.lysosomes D.mitochondria E.chloroplasts
Answer: E.chloroplasts
True or False: Proteins to be delivered to the ER lumen are synthesized on smooth ER?
Answer: False
True or False: In a typical cell, the area of the endoplasmic reticulum membrane far exceeds the area of the plasma membrane?
Answer: True
True or False: Mitochondria are bounded by a double membrane?
Answer: True
True or False: Most proteins destined to enter the endoplasmic reticulum begin to cross the membrane while still being synthesized ?
Answer: True
True or False: The RNA from the rough endoplasmic reticulum would probably encode soluble secreted proteins and plasma membrane proteins?
Answer: True
True or False: oxidative phosphorylation includes an electron transport chain?
Answer: True
True or False: Cellular respiration is essentially the opposite of photosynthesis?
Answer: True
The process that produces ATP from sugars and fats begins with a. glycolysis b. photosynthesis c. the electron transport chain d. the Krebs cycle
Answer: a. Glycolysis
Disulfide bond formation in the ER lumen a. do form in Golgi as well as in ER b. occurs by the oxidation of pairs of cysteine side chains c. stabilizes the structure of RNA d. Disulfide bonds form spontaneously in the cytoplasm
Answer: b. occurs by the oxidation of pairs of cysteine side chains
Cells of the pancreas produce and realize enzymes to the digestive system, this secretion is: a. transport secretion b. regulated secretion c. constitutive secretion d. intracellular secretion
Answer: b. regulated secretion
An individual transport vesicle: a. contains only one type of protein in its lumen b. will fuse with only one type of membrane c. is endocytic if it is going to the plasma membrane d. is enclosed by a triple membrane
Answer: b. will fuse with only one type of membrane
What is the role of the nuclear localization sequence in a nuclear protein? a. It prevents the protein from diffusing out of the nucleus through nuclear pores b. It is a hydrophobic sequence that enables the protein to enter the nuclear pore c. It is bound by cytoplasmic proteins that direct the nuclear protein to the nuclear pore d. It aids in protein unfolding so that the protein can thread though nuclear pores.
Answer: c. It is bound by cytoplasmic proteins that direct the nuclear protein to the nuclear pore
Which cellular location would you expect to find ribosomes translating mRNAs that encode ribosomal proteins? a. the nucleus b. on the rough ER c. in the cytosol d. in the lumen of the ER
Answer: c. in the cytosol
Which of the following organelles are NOT part of the endomembrane system? a. Golgi apparatus b. the nucleus c. mitochondria d. lysosomes
Answer: c. mitochondria
During exercise, the increase in respiration rate and heartbeat speed are driven by the need for a. oxygen in fermentation b. carbon dioxide in human lungs c. oxygen in muscle cell mitochondria d. oxygen in dark reactions
Answer: c. oxygen in muscle cell mitochondria
Examining the effects of mutations on nuclear pore, in which cases will nuclear proteins still be able to enter the nucleus (include those where function will be impaired, but still able to occur): a. the nuclear localization signal is mutated on a nuclear protein b. the nuclear transport receptor cannot bind to the nuclear protein c. nuclear transport proteins are mutated and the receptor d. A limited amount of kinase is available in the cell to hydrolyze the GTP
Answer: d. A limited amount of kinase is available in the cell to hydrolyze the GTP
Which reflects the appropriate order through which a protein destined for the plasma membrane travels? a. lysosome=>endosome=>plasma membrane b. ER=>lysosome=>plasma membrane c. Golgi=>lysosome=>plasma membrane d. ER=>Golgi=> plasma membrane
Answer: d. ER=>Golgi=>plasma membrane
In the early atmosphere of earth without oxygen, which cellular component would not have been useful? a. chloroplast b. nucleus c. plasma membrane d. mitochondria
Answer: d. Mitochondria
Which of the following protein families are NOT involved in directing transport vesicles to the target membrane ? a. SNAREs b. Rabs c. tethering process d. adaptins
Answer: d. adaptins
The nuclear envelope= a. formed from two cocentric membranes which are able to act as biding sites for chromomes b. contains a nuclear lamina involved in structural support c. contains an outer membrane continuous with the ER d. contains nuclear pores that allow import and export to the nucleus
Answer: d. contains nuclear pores that allow import and export to the nucleus
The ER signal sequence is guided to the ER membrane with the aid of a: a. translocation channel b. SRP receptor c. Membrane bound ribsome d. signal recognition particle (SRP)
Answer: d. signal recognition particle (SRP)
N-linked oligosaccharides on secreted glycoproteins are attached to a. nitrogen atoms in the polypeptide backbone b. serine or threonine in the sequence Asn-X-Ser/Thr c. the N-terminus of the protein d. the asparagine in the sequence Asn-X-Ser/Thr
Answer: d. the asparagine in the sequence Asn-X-ser/Thr
In a longitudinal section of a nerve cell, at the presynaptic site you note a variety of vesicles that are anchored to the plasma membrane. The vesicles must be specialized for a. constitutive secretion b. regulated secretion c. action potential d. NPC e. polarized secretion
Answer: e. polarized secretion
A radioactive labeled protein is made by cells and folled through the various organelles in the sector pathway. After six hours, all of the radioactivity is still primarily in the Golgi apparatus. This suggests that the a. protein was not translated by the ribosomes b. protein does not possess a signal peptide for localization within the lumen of the rough endoplasmic reticulum c. protein is in the nucleus d.protein was degraded e. protein possess a signal for localization within the Golgi apparatus.
Answer: e. protein possess a signal for localization within the Golgi apparatus.
Bonus Questions: Matching column 1 with column 2 Column 1 21. Peroxisomes 22.Mitochondira 23.smooth endoplasmic reticulum 24. lysosome 25.Golgi apparatus 26.secretory vesicle 27.tethering protein 28.mannose 6-phosphate Column 2 a. mediates transfer of lysosomal enzymes into lysosome b. binds vesicle to target membrane c. transport from Golgi to plasma membrane d. sorting proteins for export or to specific organelles e. presence of acid hydrolases f. biosynthesis of steroid hormones g. test for krebs cycle enzymes h. B oxidation of fatty acids
Column 1 21 peroxisomes: H 22.Mitochondira: G 23.smooth endoplasmic reticulum:F 24. lysosome: E 25.Golgi apparatus: D 26.secretory vesicle: C 27.tethering protein: B 28.mannose 6-phosphate: A
