Cell Signaling

The three stages of cell signalling are

• paracrine, local, and synaptic
• reception, transduction, and response
• transcription, translation, and folding
• alpha, beta, and gamma

1.  Each of the following numbered processes are involved in signal transduction pathways:  
 I.  Response  
II.  Amplification  
 III.  Reception  
IV.  Transduction
Which of the following represents the sequence of events in a typical signal transduction pathway?

• I, II, III, IV
• III, I, IV, II
• II, IV, I, III
• III, IV, II, I

What type of transmembrane receptor is being shown?

• G-protein receptor
• tyrosine kinase receptor
• gated ion channel

Protein kinases activate other relay proteins by adding a(n) ____ to them.

• phosphate
• ATP molecule
• cAMP
• GTP

What type of transmembrane receptor is being shown?

• gated ion channel
• G-protein receptor
• tyrosine kinase receptor

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 is being depicted in the image?

• Amplification of the signal molecule

• Enzymatic proteins inhibiting process of the signal transduction pathway

• Kinase groups adding dimer groups to other enzymes

• Diffusion of molecules within the cell due to the signaling molecule

The general name for an enzyme that transfers phosphate groups from ATP to a protein is __________.

• protein dehydrogenase

• protein kinase

• protein phosphatase

• peptidase

• protein cyclase

The source of phosphate for a phosphorylation cascade is __________.

• cAMP

• protein kinase

• GTP

• ATP

• protein phosphatase

A cell is known to respond to a particular signaling molecule. Which of the following must be true of this cell?

• It is in the heart muscle
• it is also the site of production for the signaling molecule
• It contains the receptor for the signaling molecule
• It is incapable of signal transduction