from imeng Flashcards
Term Explanation
Tight Junction
Tj are the closely associated areas of two cells whose membranes join together forming a virtually impermeable barrier to fluid. It is a type of junctional complex present only in vertebrates.
What is cell coat made of?
Glycoproteins and Glycolipids
Which glycoprotein constitutes more than 25 percent of all protein in human body?
Collagen
Which type of collagen doesn’t form fibril?
Type IV
Which ECM molecule consists of a core protein to which chains of glycosaminoglycans are covalently attached?
Proteoglycan
Which ECM molecule consists of two similar, but nonidentical polypeptides joined by a pair of disulfide bonds located near the C-termini?
Fibronectin
The degradation of extracellular materials, along with cell-surface proteins, is accomplished by a family of zinc-containing enzymes called ()
Matrix metalloproteinases (MMPs)
Which molecule is the most important family of receptors that attach cells to their extracellular microenvironment?
Integrins
Gap junctions are composed of entirely of an integral membrane protein called ()
Conexon
L-selectin means the selectins present on ()
Leukocyte
Cadherins are a large family of glycoproteins that mediate () -dependent cell-cell adhesion and transmit signals from the ECM to the cytoplasm
Ca2+-dependent
Which of the following organelle contains ribosomes ()
RER (The rough endoplasmic reticulum)
The () is thought to function as sorting station that distinguishes between proteins to be shipped back to the ER and those that are allowed to proceed to the next golgi station
The cis Golgi network (CGN)
The most common protein modification mode occurs in Golgi complex is ()
Glycosylation
Which vesicle moves materials from ER to golgi complex ()
COP II
Lysosomal proteins synthesized on rER carry a signal called ()
Mannose-6-Phosphate
For lysosomes the high internal proton concentration is maintained by a _ present in the organelle’s membrane
Proton pump
() provides a means for selective and efficient uptake to macromolecules that may be present at low concentrations in extracellular fluid, like hormones, enzymes, protein-bound nutrients
Receptor-mediated endocytosis (RME)
In general, nerve cells release neurotransmitters via () pathway
Regulated pathway
Microfilaments are composed of the protein ()
Actin
Which of the cytoskeleton molecule does not have polarity?
Intermediate filament
For the microtubules, the plus end is usually terminated by a row of ()
β-Tubulin subunits
Which protein may increase the stability of microtubules and promote their assembly?
MAP II
Motor protein () moves along microfilament
Myosin
Motor protein kinesins move along ()
Microtubules
The centrosome is a type of ()
MTOCs (Microtubule-organizing centers)
Which is not correct description about sliding-filament model of muscle contraction _
D. During contraction, the shortening of sarcomere resulted from the shortening of the filaments
What are the two main types of cell-cell adhesive junctions ()
A. Adherens junctions and desmosomes
Which type of vesicles move materials in a retrograde direction from the ERGIC and Golgi stack backward toward the ER ()
COP I
Which organelle is important for the regulated destruction of the cell’s own organelles and their replacement ()
Lysosome
Which of the following tubulin is very rare in the cell but plays a key role in nucleation of microtubules ()
γ-Tubulin
What are the four distinct families of integral membrane proteins play a major role in mediating cell-cell adhesion?
Selectins, Immunoglobulin superfamily, the Integrin family, Cadherins
Please list the organelles that form endomembrane system, and briefly describe their functions
nuclear membrane, the endoplasmic reticulum, the Golgi apparatus, lysosomes, vesicles, endosomes and the cell membrane
ECM
an organized network of ec material presented beyond plasma membrane
structute support integrity
MTOC
a variety of specialized structures that, because of their role in initiating microtubule formation, are called MTOC.
