Unit 4 Review

Which of the following would be an example of paracrine signaling in animals?

• neurotransmitter acetylcholine
• hormone epinephrine
• neurotransmitter norepinephrine
• growth factor

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

• ligand

• second messenger

• protein kinase

• receptor protein

What is a G protein?

• specific type of membrane-receptor protein

• protein on the cytoplasmic side of a membrane

• membrane-bound enzyme

• relay 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

What does a protein phosphatase do?

• removes phosphates

• transfers phosphates from ATP to proteins

• activates an enzyme with a signal molecule

Which of the following is a chemical message that usually travels through the bloodstream to target cells?

• hormone

• local regulator

• endocrine cell

What do you call it when two neurons communicate through neurotransmitters?

• Hormones
• Synapse
• Cholesterol
• Monty