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60 Cards in this Set
- Front
- Back
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Nuclear pores:
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A. Regulate entry and exit from the nucleus
B. Provide passage through only the outer nuclear membrane C. Are covered over by the nuclear lamina D. Are covered over by heterochromatin |
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Heterochromatin:
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A. Is composed of densely packed RNA and protein
B. Contains most of the actively transcribed genes C. Can be very prominent in cells that secrete a lot of protein D. Is absent from the nuclei of the majority of cells |
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Which of the following pairs is MISMATCHED?
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A. rER -- vectorial translation of proteins into the cisterna
B. golgi -- further modifications of carbohydrate portion of glycoproteins C. rER -- initial addition of carbohydrate onto a glycoprotein D. sER -- accumulation of Ca+2 from the cytosol E. lysosomes -- bud off directly from the rER |
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Which of the following pairs is MISMATCHED?
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A. microfilaments -- tubulin
B. intermediate filaments -- desmin C. microtubules -- 24 nm diameter D. microfilaments -- 5-7 nm diameter E. intermediate filaments -- 10 nm diameter |
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Which method of viewing would be most appropriate to visualize the membranes of the golgi apparatus?
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A. light microscopy of an H&E stained paraffin section
B. TEM C. SEM D. none of the above since these membranes cannot be visualized |
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In which cell type would one expect to find mitochondria with tubular or vesicular cristae?
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A. a cell that secretes steroid hormones
B. a cell that secretes digestive enzymes C. a stratified squamous epithelial cell D. an osteoblast E. a goblet cell |
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Freeze fracture of membranes has provided information on the intramembranous distribution of
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A. phospholipids
B. glycogen C. carbohydrates D. proteins E. ribosomes |
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Which of the following is/are located within the cytosol?
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A. ribosomes
B. microtubules C. IFs D. microfilaments E. all of the above |
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Polymerization of actin filaments from actin monomers requires:
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A. ADP
B. ATP C. GDP D. GTP E. No energy |
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Most mitochondrial proteins are synthesized:
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A. In the intermembranous space of the mitochondria
B. In the mitochondrial matrix C. In the nucleus D. On free polysomes in the cytoplasm E. On the rough endoplasmic reticulum (RER) |
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Before a protein can be secreted from a cell via a regulated secretory pathway, which of the following must occur:
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A. The fully synthesized protein is released from the rough endoplasmic
reticulum into the cytosol B. Mannose-6-phosphate is added to the carbohydrate side chains of the protein C. The cell receives an extracellular signal that initiates secretion of the protein D. The fully synthesized protein undergoes covalent modification in the nucleus E. The protein is transported in clathrin-coated vesicles from the rough endoplasmic reticulum to the Golgi |
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Which of the following conclusions would you most be justified in making about a cell if you observed that it had a large amount of heterochromatin?
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A. The cell is about to extrude its nucleus
B. The cell is dying C. The cell is making large amounts of protein for its own internal use rather than for secretion D. The cell is metabolically very inactive E. The cell is using a small percentage of its genome |
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The structure of biologic membranes can best be described as:
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A. a phospholipid bilayer interspersed with membrane proteins and all held together by covalent bonds
B. a fluid-mosaic of proteins interspersed in a phospholipid bilayer C. a phospholipid bilayer with the hydrocarbon tails of the phospholipids oriented toward the cytoplasm D. an internal layer of protein covered on either side by a layer of phospholipid |
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Which of the following statements regarding primary lysosomes is correct?
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A. They reproduce by division
B. They contain lysosomal DNA C. They are identifiable only after specific histochemical staining D. They contain enzymes synthesized on free ribosomes E. They are the site of β-oxidation of fatty acids |
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Which of the following statements correctly describes the nucleolus?
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A. It is a membrane-bounded intranuclear organelle
B. It is the site of synthesis of ribosomal proteins C. It is not visible in the interphase nucleus D. It is the site of assembly of ribosomal subunits |
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Glycoproteins are asymmetrically distributed in the plasma membrane with their carbohydrate moiety oriented toward the extracellular environment. In what organelle is this asymmetry established?
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A. Plasma membrane
B. Trans-Golgi network C. Rough endoplasmic reticulum (rER) D. Smooth endoplasmic reticulum (sER) |
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A nucleosome is a unit of structure of which of the following nuclear components?
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A. Nuclear matrix
B. Nuclear lamina C. Nuclear pore D. Nuclear chromatin E. Nuclear envelope |
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An epidermal germinative cell has recently replicated its DNA in anticipation of mitosis but a mitotic spindle has not yet formed. In which of the following phases of the cell cycle is this cell?
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A. Go phase
B. G1 phase C. S phase D. G2 phase E. M phase |
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Which of the following events is required to stimulate secretion of stored proteins?
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A. Influx of Na+ into the cytoplasm
B. Increase in cytoplasmic Ca+2 concentration C. Release of stored ATP from mitochondria D. Cleavage of a signal peptide from the stored protein E. Release of elementary particles stored in mitochondria |
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Colchicine inhibits cell division by which of the following processes?
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A. Inhibiting DNA synthesis in mitochondria
B. Preventing assembly of the mitotic apparatus C. Stabilizing microtubules into a rigid structure D. Preventing cytokinesis by inhibiting membrane flow E. Inhibiting the ATPase activity of G-actin |
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Tubulin polymerizes into microtubulesthat constitute which of the following cellular elements?
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A. Cores of microvilli
B. Spectrin filaments in erythrocytes C. Mitotic spindles of dividing cells D. Glial filaments in astrocytes E. Neurofilaments of axons and dendrites |
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Release of proenzymes from the pancreatic acinar cell is accomplished by which of the following processes?
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A. Exocytosis
B. Transcytosis C. Apoptosis D. Endocytosis E. Phagocytosis |
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The beating of cilia and flagella is dependent upon which of the following processes?
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A. Polymerization and depolymerization of microtubules at the tip of the cilium
B. Attachment of actin microfilaments to the membrane of the cilium C. Attachment and release of dynein side arms between adjacent microtubules of each doublets D. Attachment and release of doublet microtubules from the central pair of singlet microtubules E. Attachment and release of microtubule-associated proteins (MAPs) by doublet microtubules |
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In meiosis, synapsis is characterized by which of the following activities?
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A. Exchange of neurotransmitters between daughter cells
B. Pairing of homologous chromosomes during prophase I C. Formation of a narrow cleft between daughter cells D. Arrival of chromosomes at their respective poles |
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Nuclear lamins are intermediate filaments that
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A. bind to the nuclear envelope and prevent disassembly during mitosis
B. form the channel of the nuclear pore complex C. form the membrane of the nucleolus D. line the inner aspect of the nuclear envelope |
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Which of the following statements regarding the cell cycle is correct?
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A. It takes place once during the life of a cell (i.e., from origin to death)
B. It is an ordered sequence of events during which the cell duplicates its chromosomes and divides into two cells C. It is divided into four phases: prophase, metaphase, anaphase, and telophase D. It is divided into karyokinesis and cytokinesis, which produce two identical cells from a single parent cell E. Its divisions represent diurnal variations in the protein synthetic activity of a cell |
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Synthetic processes that occur in membrane-bounded cytoplasmic organelles include all of the following EXCEPT
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A. hydroxylation of proline and lysine in collagen synthesis
B. glycosylation of proteins C. β-oxidation of fatty acids D. polymerization of G-actin to F-actin |
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Rough endoplasmic reticulum (rER) functions in the synthesis of all of the following molecules EXCEPT
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A. collagen triple helix
B. lysosomal enzymes C. adenosine triphosphate (ATP) D. trypsinogen and pepsinogen E. N-linked glycoproteins |
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All of the following statements concerning protein secretion are correct EXCEPT
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A. zymogen granules contain stored proenzymes
B. storage granules form at the cis face of the Golgi apparatus C. post-translational modification of proteins occurs in the rough endoplasmic reticulum (rER) and Golgi apparatus D. acid hydrolases are synthesized in the rER and targeted to lysosomes E. constitutive secretion is a continuous function of all cells |
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All of the following statements concerning the nuclear envelope are correct EXCEPT:
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A. it is continuous with the membranes of the rough endoplasmic reticulum (rER)
B. it serves as the boundary between the cytoplasmic and nuclear compartments C. it contains pores that regulate passage of materials in both directions between nucleus and cytoplasm D. it is the site of synthesis of proteins that will form elements of the nuclear matrix E. it is stabilized on its inner aspect by filaments of the nuclear lamina |
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Which is FALSE? Gap junctions:
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A. provide for electrical communication between cells
B. are a part of an intercalated disc C. connect adjacent osteocytic processes within canaliculi D. are attached to actin filaments at zonulae adherentes E. permit cAMP to move between connected cells |
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Which of the following is MISMATCHED?
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A. simple squamous epithelium -- mesothelium
B. simple squamous epithelium -- endothelium C. stratified squamous, keratinized --skin surface D. stratified squamous, moist -- vagina E. transitional -- gut lining |
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What is respiratory epithelium?
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A. transitional
B. simple squamous C. pseudostratified ciliated columnar with goblet cells D. stratified columnar |
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Which of the following is NOT a characteristic feature of an epithelium?
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A. shows polarity
B. cover surfaces C. have considerable ECM D. highly cellular E. forms barriers and compartments |
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Which of the following pairs is MISMATCHED?
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A. cytokeratins -- zonula adherens
B. intermediate filaments -- vimentin C. hemidesmosome -- attachment to the basal lamina D. zonula occludens -- epithelial cell polarity |
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Each of the following is true of basement membranes EXCEPT:
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A. reticular fibers are in the fibroreticular lamina
B. collagen IV is in the lamina densa C. laminin and fibronectin are glycoproteins in the basal lamina D. functions as a place for attachment of desmosomes E. basal lamina often has both lamina rara and lamina densa |
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Which of the following distinguishes an exocrine gland from an endocrine gland?
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A. one demonstrates regulated secretion and the other demonstrates constitutive secretion
B. one secretes onto a surface or into a gland lumen that connects to a surface via a duct and the other secretes into connective tissues for distribution via the blood C. an accumulation of secretory vacuoles in an acinar structure characterizes an endocrine gland while exocrine glands are simple or compound tubular structures D. one secretes mucus and the other secretes protein-rich material E. nothing that is evident in histologic sections |
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Cadherens are transmembrane proteins involved with which of the following cell junctions?
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A. hemidesmosomes
B. focal contacts C. tight junctions D. zonula adherens E. gap junctions |
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Endothelium is a term used to describe the epithelium of:
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A. Blood vessels
B. Exocrine glands C. Lining of body cavities D. Skin |
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Endocrine glands release their product directly into/onto:
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A. Body cavities such as the pleural cavity
B. Connective tissue, with subsequent uptake by the circulation C. Ducts D. The free surface of the epidermis |
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Which one of the following cellular junctions prevents free diffusion of solutes and water through the transepithelial paracellular space?
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A. Gap junction
B. Hemidesmosome C. Adhesion belt D. Tight junction E. Macula adherens |
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The defining characteristic of exocrine glands is the presence of
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A. both serous and mucous acini in the secretory portion of the gland
B. myoepithelial cells between the secretory cells and the basal lamina C. stored zymogen droplets in the apical portion of the secretory cell D. ducts that convey the secretory product from the secretory cells to a body surface E. columnar cells in the duct system that transport sodium and water to concentrate the secretion |
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Fluorescently labeled molecules are microinjected into an epithelial cell. Ten minutes later, the presence of the probe molecules is detected in adjacent, uninjected cells. This is evidence that the cells are joined by
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A. desmosomes
B. adhesion belts C. gap junctions D. tight junctions E. junctional complexes |
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The mammary gland is classified as an exocrine gland because of which one of the following characteristics?
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A. Connective tissue capsule
B. Extraepithelial location C. Association with myoepithelial cells D. System of drainage ducts E. Tubuloacinar secretory units |
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The terminal web of an epithelial cell is anchored peripherally to
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A. adhesion belts
B. gap junctions C. desmosomes D. basal laminae E. tight junctions |
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Which one of the following describes the secretory mechanism by which sebum is produced?
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A. Apocrine
B. Cytocrine C. Eccrine D. Holocrine E. Paracrine |
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A connexon is a structural component of the
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A. adhesion belt
B. macula adherens C. gap junction D. tight junction E. desmosome |
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Consider the desmosome. Which of the following statements is TRUE?
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A. Sometimes it is called a nexus.
B. Provides for the passage of large proteins from one cell to an adjacent cell. C. Has a plaque formed of many connexons. D. Facilitates metabolic coupling between adjacent cells. E. A disc-shaped adhesion site between epithelial cells. |
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A 24-year-old graduate student who has chronic lower respiratory tract infections seeks advice from an ear, nose and throat specialist. A biopsy of the student's respiratory epithelium was examined via electron microscopy and found to have abnormal:
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A. microvilli
B. desmosomes C. cilia D. hemidesmosomes E. basal plasmalemma infoldings |
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Consider the characteristics of an epithelium. Which of the following is TRUE?
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A. polarized
B. vascular C. encased within a basal lamina D. contain wide intercellular spaces E. The only basic tissue that does not contribute to the wall of a blood vessel. |
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Synthesis of hyaluronin occurs in/on which of the following cell structures?
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A. Golgi
B. Lysosomes C. Late endosomes D. Rough endoplasmic reticulum (rER) E. Cell surface (plasma membrane) |
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Concerning collagen:
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A. type IV is present in the lamina densa of basal laminae
B. type III of reticular fibers isstainable with silver C. it is the most abundant protein of the body D. all collagens exist as fibers E. only "A", "B" and "C" are correct |
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A histologic section of connective tissue shows numerous cells containing large numbers of uniformly sized basophilic granules. The cells are ovoid, with a centrally located nucleus, and are aligned along blood vessels. The cells are most likely
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A. plasma cells
B. macrophages C. eosinophils D. mast cells E. fibroblasts |
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Which is NOT a cross-banded collagen?
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A. collagen I
B. collagen II C. collagen III D. collagen IV E. all of the above are cross-banded collagens |
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Which of the following pairs is MISMATCHED?
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A. macrophages -- phagocytic cells that present antigens to T lymphocytes
B. multilocular adipocytes-- function to generate heat C. neutrophil -- bilobed nucleus, specific cytoplasmic granules with antiparasitic proteins D. mesenchymal cell --stellate cell of embryonic mesoderm; precursor of most of fixed cells of connective tissues E. basophil or mast cell -- heparin and histamine |
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Which of the following does NOT synthesize collagen?
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A. fibroblast
B. chondrocyte C. osteoblast D. macrophage E. Schwann cell |
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Sulfation of sugars in proteoglycans occurs in which of the following cell structures?
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A. Golgi
B. Peroxisomes C. Late endosomes D. Rough endoplasmic reticulum (rER) E. Smooth endoplasmic reticulum (sER) |
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Which of the following statements accurately describes tropocollagen?
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A. It is an aggregate of collagen fibrils forming large banded fibers
B. It is the basic molecule from which collagen fibrils self assemble C. It is the precursor polypeptide of procollagen D. It can be recognized in electron micrographs by its 64 - 68 nm axial periodicity E. It is polymerized into collagen fibrils in the Golgi apparatus |
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Which cells are primarily responsible for the synthesis of extracellular matrix components in adult loose connective tissue?
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A. Adipocytes
B. Fibroblasts C. Macrophages D. Mesenchymal cells E. Myofibroblasts |
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USE THE DIAGRAM BELOW FOR QUESTION #60
The banded structure shown in the diagram above represents one: |
A. Collagen type I fibril
B. Collagen type II fiber C. Collagen type IV fibril D. Tonofilament E. Tropocollagen molecule |
