Cell Communication

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

• ligand
• second messenger
• protein kinase
• receptor protein

Which of the following can activate a protein by transferring a phosphate group to it?

• cAMP
• G Protein
• protein kinase
• protein phosphatase

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

Signal amplification is most often achieved by

• an enzyme cascade
• binding of multiple signals
• branching pathways
• action of adenylyl cyclase

What does a protein kinase do?

• removes phosphates
• transfers phosphates from ATP to proteins
• activates an enzyme

Hormones are used in ____ signaling.

• endocrine
• juxtacrine
• autocrine
• paracrine

How do bacteria sense local population density?

• quorum sensing

• bacteria sensing

• signal sensing

• population sensing

Local signaling in animals is called what?

• paracrine

• endocrine

• hormone

• gap junctions

Long distance signaling in animals is called what?

• paracrine

• endocrine

• hormone

• gap junctions

An example of LOCAL cell communication is:

• White blood cells bumping into each other sharing antigen info

• Neurons communicating across a synapse

• Hormones traveling through the blood stream to target tissues