Module 10 Flashcards
Membrane Transport
What part of the bilayer is hydrophobic
interior
Hydrophilic part of bilayer
exterior
Cholersterol
Lipid
Thicker and impenetrable, but softer
What makes the membrane semipermeable
structure and mic of proteins and lipids included
How is membrane fluidity influenced
Types of lipids
Why is membrane fluidity important
for what system?
Allows membranes to break and reform for the movement of substance through the endomembrane system
What is the cell membrane a selective barrier to what
, polar, charged, and large molecules
Why can them membrane act as selective
combo of lipids and protiens
Interior of the bilayer prevents what from entering the cell
hydrophobic nonpolar
Charged ions and polar molecules
Large molecules
polysaccharides, proteins
Small gasses
o2, co2, n2
Transport proteins can facilitate movement of
water, ions, and nutrients
How do chemical reactions occur
as a result of interactions between molecules and cannot occur unless they bump into eachother
Concentration gradient
There are areas of higher and lower concentration
Diffusion’s net movement
area of high to low concentration
diffusion is a result of
random movement of molecules
Dynamic equalibrium
movement of molecules in both directions continues
Passive transport
Molecules move across the membrane by diffusion, as a result of concentration difference between the inside and outside the cell
What hydrophobic molecules can diffuse into the cell
why
steroids, lipids
the lippid bilayer is also hydrophobic
Transport protien
Transmembrane protein that spans the cell membrane and provides a route for substance to enter and exit the cell
Facilitated Diffusion
diffusion across a cell through a transport protein
high to low concentration
Channel protein
Type of transport protein
Provides opening between the inside and outside of the cell where certain molecules can pass, depending on shape and charge
Gated channel protiens
open in response to some sort of signal; chemical or electrical
Carrier Protein
Binds to and then transports specific molecules across the cell membrane
When binding happens, shape changes to allow molecule to move across the bilayer