Cell Signaling

A signal molecule that binds to a plasma-membrane protein is a

• ligand
• second messenger
• protein kinase
• receptor protein

What do second messengers do?

• transport a signal through the lipid bilayer
• relay a signal from the outside to the inside of the cell
• relay message from the inside of the mebrane throughout the cytoplasm
• dampen the message

What determines whether a cell is a target cell for a particular signal molecule?

• phosphorylation cascade
• cAMP
• signal receptors
• phosphatase

In cell signaling, how is the flow of specific ions

regulated?

• Opening and closing of ligand-gated channels

• Transduction

• Cytoskeleton rearrangement

• Endocytosis

What is a G protein?

• A protein on the cytoplasmic side of the a membrane that becomes activated by a receptor protein

• A specific type of membrane receptor protein

• A membrane bound enzyme that converts ATP to cAMP

• A tyrosine kinase relay protein

Many signal transduction pathways use second messengers to:

• transport a signal through the lipid bilayer portion of the plasma membrane.

• relay a signal from the outside to the inside of the cell.

• relay the message from the inside of the membrane throughout the cytoplasm.

• amplify the message by phosphorylating proteins.

The 3 steps of signal transduction in order are

• reception, transduction, response
• response, transduction, reception
• reception, response, transduction
• transduction, reception, response

Which type of membrane protein would help intake a message from outside of the cell to inside of the cell?

• Receptor Protein

• Enzymatic Protein

• Channel Protein

• Junction Protein

• ATP Synthase

Ligands are signaling molecules that bind to receptors. Which of the following statements is true of ligands?

• All ligands are proteins.

• Each ligand is only able to bind to one specific receptor

• Ligands can bind to cell-surface receptors, but they cannot enter the cell

• Ligands bond to receptor proteins and cause the protein to relay a message to intracellular proteins.

Which letter represents the ligand?

• A

• B

• C

• D

• E