ch. 5 bulk transport by endocytosis and exocytosis Flashcards
the substances cells required for growth are mostly large, polar molecules that cannot cross the hydrophobic barrier a lipid bilayer creates. two processes are involved in this bulk transport:
endocytosis and exocystosis
endocytosis and the three major types of endocytosis cells use:
-the plasma membrane envelops food particles and fluids
-like active transport, these processes also require energy expenditure.
1. phagocytosis
2. pinocytosis
3. receptor-mediated endocytosis
if the material the cell takes in is particulate (made up of discrete particles), the process is called
phagocytosis
If the material the cell tales in is liquid, the process is called
pinocytosis (pino=vino=wine=liquid)
-common among animal cells
molecules are often transported into eukaryotic cells through ______ - ________ _________. These molecules first bind to specific receptors in the plasma membrane.
receptor-mediated endocytosis
the portion of the receptor molecule that lies inside the membrane is trapped in an indented pit coted on the cytoplasmic side with the protein
clathrin
endocytosis in itself brings substances directly into the cytoplasm of a cell. true or false? and why?
false, the material taken in is still separated from the cytoplasm by the membrane of the vesicle.
the reverse of endocytosis is ______, the discharge of material from vesicles at the cell surface.
exocytosis
-in plant cells, exocytosis is an important means of exporting the materials needed to construct the cell wall through the plasma membrane.