Transport of Materials Flashcards
examples of passive transport
simple diffusion
facilitated diffusion
osmosis
filtration
type of passive transport where it moves a substance from an area of higher concentration down its concentration gradient
diffusion
example of substance that can easily diffuse
oxygen
carbon dioxide
steroids
vitamins (A,D,E,K)
Urea
Glycerol
Small alcohol
Ammonia
why does cholesterol and lipids can easily pass through the cell membrane?
they have the same nature as the bilayer
one of the great multitaskers of biology
cell membrane
determines what molecule can move into or out of the cell and is mainly responsible for maintaining the delicate homeostasis of each cell
phospholipid bilayer
simplest transport across a membrane, does not require the cell to expend any energy and involves a substance diffusing down its concentration gradient across a membrane
simple diffusion
region of space over which the concentration of a substance changes and substances will naturally move down their gradients, from an area of higher to an area of lower concentration
concentration gradient
type of substances that is easier to pass through the semi-permeable membrane
small, no charge
example of diffusion
gas exhange
perfume
type of facilitated diffusion
carrier-mediated
channel
integral proteins that are specific for transporting certain polar molecules or classes of molecules, such as sugars and amino acids, that are too large to pass through the membrane channels
carrier
property of the carrier that allows it to first envelop and then release the transported substance, shielding it en route from the nonpolar regions of the membrane
alterations in the shape
transmembrane proteins that transport substances, usually ions or water through aqueous channels from one size of the other c
channels
are selective due to pore size and the charges of the amino acids lining the channel
channels
always open and simply allow ions for water to move according to concentration gradients
leakage channels
controlled (opened or close) by chemical or electrical signals
gated channels
diffusion that is helped along (facilitated by) a membrane transport channel
facilitated diffusion
proteins with carbohydrates that allow molecules to pass through the membrane
glycoproteins
net movement of water across a semipermeable membrane from an area of lower solute concentration to an area of higher solute concentration
osmosis
important in many biological processes, as it often takes place at the same time that solutes diffuse or are transprted
osmosis
refers to the ability of a solution to change the shape or tone of cells by altering the cells’ internal volume
tonicity
meaning of tono
tension
more dilute than cells cells placed in this solution enlarge rapidly as water rush inside
hypotonic solution
percentage of salt and water inside the cell
0.9 NaCl
99.1 water
have the same concentration of non-penetrating solutes as those found in the cell
isotonic solution
higher concentration of non-penetrating solutes that seen in the cell, cells immersed in this solution lose water and shrink
hypertonic solution
process where red blood cell is destroyed due to immersion in a hypotonic solution
hemolysis
term to call a plant cell immersed in a hypotonic solution
turgid (normal)
term to call a plant cell immersed in a isotonic solution
flaccid
term to call a plant cell immersed in a hypertonic solution
shriveled
describes an object’s shape, especially a leaf or shell, as being round-toothed or having a scalloped edge after the exposure of a cell to a hypertonic solution1
crenation
happens when physical pressure pushes fluid through a selectively permeable membrane
filtration
drives filtration
pressure
example of biological filter
kidneys
the cell membrane permits only those substances which are soluble and could easily pass through its pores.
filtration
examples of active transport
primary AT
secondary AT
bulk transport
types of bulk transport
exocytosis
endocytosis
type of endocytosis
phagocytosis
pinocytosis
receptor-mediated endocytosis
like facilitated diffusion, requires carrier proteins that combine specifically and reversibly with the transported substances
active transport
driving force of facilitated diffusion
kinetic energy
move solutes most importantly ions “uphill” against a concentration gradient
active transporters/ solute pumps
what type of cells does not have sodium-potassium pumps
plant cells
what are the pumps in plants are releasing
Hydrogen
Calcium
what helps pumps in plants to release hydrogen and calcium
ATP
what happens to the ATP when the Na binds to the protein
ATP breaks down into ADP and a high-energy phosphate group
what part of the ATP breakdown products powers the pump protein to change its shape
phosphate group
what happens to the Na when the pump protein is powered
expelled into the ECF
kind of pump that is seen into the vacuole’s membrane
hydrogen pump
release the proton outwards the cell
hydrogen pump
what happens when the protein changes in shape after the Na is expelled into the ICF
favors the binding of K in the ECF
difference between primary and secondary transport
primary - derived from ATP breakdown, chemical energy
secondary - derived from electrochemical energy stored in the ionic concentration differences
move one type of molecule in one direction
uniporters
move several molecules in one direction through the use of kinetic energy
symporters
move different molecules in opposite directions
antiporters
another mechanism to receive nutrients going inside the cell
secondary active transport
pumps sodium and potassium in different directions
sodium-potassium pump
result of different concentrations inside and outside the cell
resting membrane potential
ratio of sodium going out and potassium going in
3:2
will move inside the cell due to the concentration gradient
high concentration
what happens to the hydrogen ion in secondary active transport
bind to the protein to be released
when a vesicle fuses with the membrane at the cell surface, its contents are deposited outside the cell and the vesicle membrane parts become part of the cell surface
vesicle transport
numerous organelles produce these that move through the cell, either remaining discrete or fuse with other organelles or vesicles
vesicles
membrane _______ prevents two compartments from fusing
dissimilarity
example of dissimilarity of membrane
nucleus = mitochondria or cholorplast
cell eating
phagocytosis
meaning of phago
to eat
meaning of pino
to drink
process in which a cell internalizes non-particulate materials such as proteins by engulfing them in an energy-dependent manner
endocytosis
extends from the cell to surround the particle to be taken into the cell by phagocytosis
pseudopods
formed after the pseudopods fuse with the particles
phagosome
waits for the liquid to enter
pinocytosis
membrane forms inward to form this
pinocytic vesicle
uptake of substances by the cell is targeted to a single type of substance that binds at the receptor on the external cell membrane
receptor-mediated endocytosis
bind to the receptor in receptor-mediated endocytosis
ligand
release larger molecules that might be used by other cells
exocytosis
membrane of the secretory vesicles fuses with that of the plasma membrane and secretory product is released into the exterior of the cell
exocytosis
