FINAL EXAM COMPLETE SOLUTIONS AND
CORRECT ANSWERS GRADED A+
⩥ Plasmodesmata. Answer: Channels through cell walls that connect the
cytoplasms of adjacent cells
⩥ Integrins. Answer: transmembrane protein attaches the extracellular
matrix and the cytoskeleton
⩥ Tight Junctions. Answer: Membranes of neighboring cells are pressed
together, preventing leakage of extracellular fluid, like grandmas
knitting.
⩥ Desmosomes. Answer: Anchoring junctions that prevent cells from
being pulled apart.
⩥ Gap Junctions. Answer: Allow molecules to pass directly from cell to
cell.
⩥ Endomembrane system. Answer: Series of interacting organelles
between nucleus and plasma membrane that regulates protein traffic and
performs metabolic functions in the cell
,⩥ DNA in Eukaryotic Cells. Answer: DNA located in Nucleus,
Mitocondria and Chloroplast.
⩥ Cholesterol. Answer: Is a lipid that gives the cell membrane more
structure making it less fluid. Fits in between all the lipids in the cell
membrane.
⩥ Glycoproteins. Answer: Forms hydrogen bonds with the water
molecules surrounding the cell and thus help to stabilize membrane
structure
⩥ Glycolipid. Answer: The main function of glycolipids in the body is to
serve as recognition sites for cell-cell interactions. The saccharide of the
glycolipid will bind to a specific complementary carbohydrate or to a
lectin (carbohydrate-binding protein), of a neighboring cell.
⩥ Phospholipids. Answer: form the basic structure of a cell membrane,
called the lipid bilayer.
⩥ Peripheral Proteins. Answer: found on the surface of the membrane,
some of their functions are; some act as receptors, some as enzymes,
catalyzing the reaction and since many are cytoskeletons, they give a
cell its shape, offers support, and facilitates movement through three
main components: micro filaments, intermediate filaments, and micro
tubules
, ⩥ Integral Proteins. Answer: proteins which penetrate the hydrophobic
core of the lipid bilayer include transporters, linkers, channels, receptors,
enzymes, structural membrane-anchoring domains,
⩥ Extracellular Matrix. Answer: The substance in which animal tissue
cells are embedded, consisting of protein and polysaccharides. such as
providing support, segregating tissues from one another, and regulating
intercellular communication
⩥ Cytoskeleton. Answer: A network of long protein strands in the
cytosol that helps support the cell
⩥ Lipid Rafts. Answer: rigid region of membrane involved in signaling
and interacting with messenger molecules
⩥ Fluid Mosaic Model. Answer: A model that refers to how the lipid
bilayer tends to act more like a liquid than a solid.
⩥ Molecular Movement Across Membrane. Answer: Due to Osmosis,
passive transport or active transport uses energy to go against the
gradient.
⩥ Aquaporins. Answer: Channel proteins that facilitate the passage of
water