Membrane Transport Flashcards
refers tothe movement of particles (solute) across or through a membranous barrier
membrane transport
Type of Membrane Transport
Passive
Active
type of membrane transport that does not require energy to move substances across cell membranes.
passive transport
Types of Passive Transport
Diffusion
Facillitated Diffusion
Osmosis
the movement of molecules or ions across a cell membrane from a region of lower concentration to a region of higher concentration—against the concentration gradient.
Requires cellular energy to achieve this movement
Active Transport
Types of Active Transport
Primary & Secondary Active Transport
Endocytosis & Exocytosis
The outermost component of cell and forms the boundary between material inside and outside material
Cell membrane
Acting as a barrier that determined what moves into and out of the cell
Cell membrane
Cell membrane consist of
Extracellular substances
Intracellular substances
It is which a cell membrane have that allows only certain substances to pass in and out of the cell
Selective Permeability
Some materials can pass through while others are excluded
Selectively Permeable Barrier
High Concentration Inside the Cell
Enzymes
Glycogen
Potassium
High Concentration Outside the Cell
Sodium
Calcium
Chloride
involved in the movement of substance both entry and exit in the cell. They transport substances without binding to them and without spending energy
Transmembrane Protein Channel
It is substance that can pass directly through the cell membrane’s phospholipid bilayer
O2
CO2
In cell membrane some substances must pass through? Like?
Transmembrane protein channel
Na+
Route of transport through the membrane depends on
Size
Shape
Charge of substance
What do glucose required to be transported across the cell membrane
Carrier molecules
Some substances also require ____ across the membrane
Vesicular Transport
It must fuse with the cell membrane for transport
Vesicle
Membrane Characteristics
Selectively Permeable
Asymmetric
Amphiphilic
2 Basic Methods of Movement Through Cell Membrane
Passive Transport
Active Transport
Homogeneous mixture of two or more components
Solution
Example of Solution
Air
Fluid of Plasma Membrane
Seawater
Rubbing alcohol
Disolving medium
Typically water in the body
Solvent
Components in smaller quantities within a solution
Solute
The difference in the concentration of a solute in a solvent between two points divided by the distance between the two points
Concentration Gradient
Passive movement of molecules from an area of high concentration to an area of low concentration
Diffusion
3 Condition that molecules will move by diffusion
- Molecules are small enough to pass through the membrane’s pores (channels formed by membrane proteins) (FD)
- The molecules are lipid-soluble (D)
- The molecules are assisted by a membrane carrier (FD)
Types of Cell Membrane Channel
Leak Channels
Gated Channels
Constantly allow ions to pass through
Leak channels
Limit the movement of ions across the membrane by opening and closing
Gated channels
Diffusion of water across selectively permeable membrane, such as the cell membrane, from a region of higher water concentration to one of lower water concentration
Osmosis
Pressure created by water moving across the membrane due to osmosis
Osmotic Pressure
The more water moving across the membrane, the?
Higher the osmostic pressure
Diff. Solution
Hypotonic Solution
Hypertonic Solution
Isotonic Solution
where the water moves
Hypertonic areas
Lower solute concentration compared to the intracellular solute concentration
lower concentration of solute than another solution, meaning water will flow out of it
Swell
Hypotonic Solution
higher concentration of solute than another solution, meaning water will flow into it
Hypertonic solution
same solute concentration and water concentration compared to body fluids
Isotonic solution
Cell Swell
Hypotonic
Cell Shrink
Hypertonic
Cell neither shrink nor swell
Isotonic
Proteins within the cell membrane
Carrier molecules
Carrier molecules are involved in this mechanism which move large, water-soluble molecules or electrically charged ions across the cell membrane
Carrier-Mediated Transport Mechanism
It is where molecule to be transported bind on one side of the molecule
Specific Carrier Molecule
Carrier Mediated Trasport Mechanism Include:
Facilitated Diffusion and Active Transport
Exhibit specificity which means only specific molecules are transported by the carriers
Carrier Mediated Transport Mechanism
Does not require ATP for energy
Facilitated Diffusion
Does require ATP for transport
Active Transport
Carrier-mediated
transport process that
moves substances from an
area of high concentration
to an area of low
concentration with the help
of a transport molecule
Facilitated Diffusion
Carrier-mediated process
that moves substances
across the cell membrane
from regions of lower
concentration to those of
higher concentration
against a concentration
gradient
Active Transport
Primary Active Transport
NaK Pump
Moves Na+ out of cells and K+ into cell
Sodium-Potassium Pump
Sodium Potassium Pump is necessary for
Nerve Impulses
Result of Sodium-Potassium Pump
Higher Concentration of Sodium/Na+ outside cell
Higher Concentration of Potassium/K+ inside cell
Secondary Active Transport
Cotransport
Countertransport
The diffusing substance moves in the same direction as the transported substance
Cotransport
The diffusing substance moves in the direction opposite to that of the transported substance
Countertransport
Large water-soluble
molecules, small pieces of
matter, and even whole
cells can be transported
across cell membranes in
membrane-bound sacs
called
Vesicle
Uptake of material through the cell membrane by the formation of a vesicle
Endocytosis
Endocytosis
Receptor-Mediated
Phagocytosis
Pinocytosis
occurs when a specific
substance binds to
the receptor molecule
and is transported
into the cell
Receptor-Mediated Endocytosis
Used for endocytosis
when solid particles are
ingested
Engulf large particles
Protective mechanism,
not a means of getting
nutrients
Phagocytosis
Cell-Eating
Phagocytosis
Smaller vesicles are formed,
they contain liquid rather than
solid particles
Plasma membrane forms a pit,
and edges fuse around droplet
of fluid
Cell “gulps” droplets of extracellular fluid cobtaining dissolved protein or fats
Pinocytosis
Cell-Drinking
Pinocytosis
Process when secretory vesicles move to the cell membrane, where the membrane of the vesicle fuses with the cell membrane and the material in the vesicle is eliminated from the cell
Exocytosis
