Transport Mechanism Flashcards
Regulates passage of molecules into and out of the cell
Provides mechanical shape and strength
Maintains cellular homeostasis
Cell membrane
TRANSPORT OF MATERIALS ACROSS THE CELL MEMBRANE
Passive and active transport
It moves molecules and ions from a higher concentration to lower concentration without any energy
Passive transport
It moves molecules and ions from lower concentration to higher concentration with the help of energy in the form of ATP
Active transport
Types of passive transport
Diffusion
Facilitated diffusion
Osmosis
It is the net movement of molecules from an area of greater concentration to an area of low concentration.
Diffusion
It is the movement of molecules through the plasma membrane with the help of carrier proteins or permeases which changes its shape when a molecule attaches to it.
Facilitated diffusion
It is the diffusion of water down its concentration gradient through the cell membrane.
Osmosis
For water to travel at a fast rate across the membrane, it passes through channel proteins
Aquaporin
Types of cell environment
Isotonic
Hypotonic
Hypertonic
A cell and its surrounding have equal solute concentrations.
Isotonic
Cell outside environment has less solute than the interior of the cell
Water moves from outside to inside of the cell, resulting in bursting in animal cell. and turgidity in plant cells.
Hypotonic
Cell outside environment has greater solute concentration than its inside environment.
Water moves out of the cell, which may shrink cells
Hypertonic
bursting of the cell due to a hypotonic environment
Cytolysis
shrinking of cells due to a hypertonic environment
Plasmolysis
Involves the movement of large and polar molecules into and out of the cell membrane. It involves the formation of membrane-bound sacs or vesicles that pinch off from the cell membrane
Bulk transport
The cell engulfs particles into a pouch formed by the infolding of the cell membrane.
Endocytosis
3 types of endocytosis
Phagocytosis
Pinocytosis
Receptor mediated endocytosis
“Cell Eating” the cell engulfs solid particles into much larger vesicles.
Phagocytosis
“Cell Drinking” the cell engulfs droplets of fluid.
Pinocytosis
the cell membrane fold inward forming a pit lined with receptor proteins which bind to specific type of molecules.
The coated pit then moves into the cytoplasm.
Receptor mediated endocytosis
