cell membrane & transport

Created by

adri

Cards (33)

what is a cell membrane?
they are like the cells gatekeepers, they handle movement coming in and out and keeps the cells gate in shape
is cholesterol a normal component in our cell membranes?
yes
what is a plasma membrane?
it controls what goes in and out for balance
what happens if the internal part of a cell isnt balanced ? (if the plasma membrane doesnt do its job of balancing the cell)
it can lead to dysfunction or cell death
the plasma membrane has a selective permeability barrier that ensures that...
the inside of the cell is different from the outside
why must cells use a lot energy?
to maintain the chemical balance of the right mix of stuff, inside and wrong stuff, out
what are transport proteins?
Proteins that transport molecules across cell membranes.
what is passive transport?
movement of molecules across a cell membrane without the use of energy
what is active transport?
Movement of molecules across a cell membrane that requires energy
what is diffusion?
The movement of particles from an area of high concentration to an area of low concentration
what is an equilibrium?
it is when things are evenly spread, like mixing sugar in water until it stops dissolving
what can increase the rate of diffusion?
heat
do small substances diffuse faster than larger substances?
yes
what is osmosis?
water moving through a barrier to balance out the concentration levels
what is a hypotonic solution?
it is when there is a less of a concentration outside the cell, so water rushes in making it swell
what is a hypertonic solution? 
it is when there is more stuff outside of the cell, so water leaves making it shrink
what is an isotonic solution?
it is when the stuff inside and outside of the cell is balanced and equal
what are ways in which substances can move across membranes?
by passive(without) or active transport(with energy) and/or simple(without) or facilitated diffusion (with proteins)
what can easily pass through cell membranes without assistance?
O2 and CO2 through simple diffusion (without transport protein)
what is facilitated diffusion?
the passive transport of molecules across a cell membrane with the help of transport proteins.
what are the two transport proteins that makes up facilitated diffusion?
channel proteins and carrier proteins.
what are channel proteins?
they help substances move through the membrane without needing energy
what are carrier proteins?
they carry specific molecules across the membrane based on their shape
what are two types of carrier proteins?
passive and active carrier proteins
what is exocytosis?
it is when substances from a cell is sent out by merging transport vesicles with the membrane
what is endocytosis?
it is when the cell brings stuff in by wrapping it in a membrane section
what are the 3 main cell junctions in animal cells?
tight, anchoring and gap junctions
what is a tight junction?
tight belts of proteins that make leak-proof sheets in the body
what is an anchoring junction?
like protein patches that connect cells under a lot of stress
what are gap junctions?
like tunnels between cells made of proteins for direct connections
what is plasmodesmata?
like tunnels connecting cells through the cell wall for communication
what is a target cell?
it gets a signal through a receptor protein on the surface or inside of a cell
what is signal transduction?
signals at the cell surface that need a pathway to be relayed inside