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What is a receptor?
This is the protein that receives a chemical signal, such as a hormone or neurotransmitter.
What is an ion channel?
This type of receptor opens a channel that allows ions such as Na⁺, K⁺, Ca²⁺, or Cl⁻ to move across the membrane.
ANTIGENS
glycoproteins that serve as ID for the cell
What is a ligand?
A signaling molecule that binds to a receptor is called this.
What happens when a ligand binds?
The channel opens or closes
what is pinocytosis
the cell "drinks" by engulfing dissolved ions and other solutes in the liquid medium.
What is a conformational change (change in shape)?
If a ligand fits into a receptor like a key into a lock, this happens to the receptor.
Signal affects the same cell that released it
autocrine
Taking in a large particle/bacterium
phagocytosis
What are intracellular receptors? with examples
These receptors are located inside the cell and can bind signaling molecules that are small or nonpolar enough to cross the membrane. ex steriods
Which is generally faster: an ion-channel receptor or an enzyme-linked receptor?
ion-channel receptor — it can open/close almost immediately and directly change ion movement across the membrane.
Insulin vesicle fuses with membrane and releases insulin
exocytosis
Why can't most large, polar signaling molecules simply pass through the plasma membrane and bind to intracellular receptors?
Because the inside of the phospholipid bilayer is hydrophobic, so large/polar molecules cannot easily cross it.
Prevents substances from leaking between cells
tight junctions
Hormone travels through the bloodstream and binds a GPCR:
signal type?
receptor type?
endocrine and GPCR