2.6 & 2.7 Transport Mechanisms and Facilitated DIffusion Flashcards
What are the 2 key differences that differentiates passive transport from active transport?
no cell energy needed
substances move from high concentrations to low concentrations
what are the 3 types of passive transport?
osmosis
simple diffusion
facilitated diffusion
Describe osmosis
water moving directly through PM; no channel
- water small; coming slowly
aquaporins also osmosis- passive channels
Describe simple diffusion
Diffusing substances that are small and non-polar
ex. O2, CO2, N2, non polar amino acids
Describe facilitated diffusion
substances that need protein helpers- large polar molecules
What are the two types of facilitated diffusion?
protein channels and protein carriers
What differentiates active transport from passive transport?
requires energy
substances move from low to high concentrations
WHat are the 3 types of active transport?
Endocytosis
Exocytosis
Protein pump
what are the 3 types of endocytosis?
pinocytosis: liquid
phagocytosis: solid
receptor-mediated endocytosis: receptor proteins on the cell membrane are used to capture specific target molecules
What are some examples of things can go through protein carriers?
polar amino acids; polar glucose
Which factor is more important when deciding the type of transport?
Polarity> size
Define tonicity
solute concentration on one side of the membrane compared to the other side
Solute define
substances that gets dissolved
define solvent
substances that does the dissolving
Hypertonic solution define
the side with the more solute concentration
Hypotonic solution define
the side with more solvent concentration
isotonic soluion define
solute concentration is equal on both sides
crenation define
only in animal cells- cell has shrunk and cytoplasm shrins
plasmolysis define
only in plant cells- cell membrane pulls away from cell wall and central vacuole shrins
What types of tonicity is ideal for animal cells?
Isotonic
What type of tonicity is ideal for plant cells?
hypotonic- the cell is a turgid cell
the more water in a plant means the more pressure so there would be more stiffness in the cell wall
Flaccid cell define in plants
Occurs in isotonic solutions; cell lacing turgidity
Define phosphorylation
addition of phosphate
define conformational change
shape changes of a protein
What are the 2 sources of energy for active transport ?
ATP- primary AT
Separation of charge across membranes- secondary AT
Na/Glucose Symporter
carrier protein that transports 2 substances in the same direction
SGLT) on apical side of epithelial cells lining small intestine
Secondary AT define
a 2nd molecule piggy bacs with a first molecule to move actively using the indirect source of energy from the membrane potential
Na/ K Pump
three sodium’s pump out of the cell
2 K+ into the cell
Phosphate is used
Define co-transport
secondary active transport that use the energy from an electrochemical gradient to transport 2 different ions across the membrane through a membrane
Define Uniport:
membrane transports a single ion in and out of the cell
Define symport
2 different ions are transported in the same direction
define anitport
2 different ions are transported in the opposite direction
Define electrochemical gradient
type of concentrtaion gradient
membrane potential- electrical potential different (voltage) across a membrane
membranes can be polarized by movement by ions across membranes-
what is glut
glucose transporter on basolateral side of epithelial cells lining small intestine delivering glucose to blood capillaries
