test 2 Flashcards
In order to survive cells must…
take in nutrients from the nonliving environment outside of the cell and dispose of the wastes in the cell. These prosseses happen through the cell membrane.
What is the man function of the cell membrane?
The main function of the cell membrane is to regulate what enters and exits the cell.
The cell membrane is made up of two layers of _____ and a variety of ______ ______ are embedded throughout it.
Lipids, Protein Molecules.
What are gatekeeper proteins?
Gatekeeper proteins open and close a gate allowing proteins to move through the membrane. Also known as facility diffusion, which allows materials through more quickly then regular diffusion because it doesn’t use the cells energy.
What are hormone receptor proteins?
Receptor proteins attach to hormones on the membrane and pass the chemical message to the cell. Hormones have a special shape the fits perfectly into the receptors on the membrane.
What are Identification proteins?
Identification proteins recognize the type of nearby cell. If the cell is not recognized it may be attached by the immune system.
What are carrier proteins?
Carrier proteins receive energy and then
capture specific molecules to move either into or out of the cell.
What is passive transport?
The movement of nutrients through the membrane without using energy.
What are the three man ways of passive transport?
Diffusion, Osmosis, facilitated diffusion
What is diffusion?
Diffusion occurs when there is an unequal concentration of molecules. The molecules go from a higher concentration to a lower concentration until there is an equilibrium
What is osmosis?
is the diffusion of water through a
selectively permeable membrane. The membrane is
permeable to water, but impermeable to the larger
molecules. Water diffuses from an area of high water
concentration to an area of lower water concentration
until the equilibrium between water and solute is reached.
Isotonic
concentration of souls is equal
Hypotonic
concentration of solutes is less outside then inside
Hypertonic
concentration of solutes is more outside then inside
facilitated diffusion
faster then regular diffusion, involves a carrier protein, does not require energy.
what is an example of facilitated diffusion?
Glucose
what is active transport?
active transport is the movement of materials from an area of low concentration to high concentration using energy.
endocytosis
when the cell engulfed large particles by extending its cytoplasm.
pinocytosis
occurs when the cell engulfs liquid particles
phagocytosis
occurs when the cells engulfs large molecules or even whole cells.
exocytosis
moment of large particles exiting the cell. small vesicles break of the Golgi body and fuse to the membrane allowing them to leave
homeostasis
the internal environment of the organisms stays the same even when the external environment changes.
channel proteins
allow different shaped particles to pass through
carrier proteins
only allow specifically shipped particles to pass through.
gate proteins
particles attach to the protein which opens the gate allowing the particle to pass through
cholesterol
allows cell membranes to function in a wide range of temperatures. at low temps it keeps it rigid and high temps it keeps it flexible.
phospholipid bilayer
a two layer membrane hydrophobic tails pointing inward. hydrophilic heads pointing outward.
carbohydrate chain
provide unique fingerprints for the cell
integral protein
contains protein channels for molecules to pass through
peripheral protein
a protein found on only one side of the bilayer.
