Endocrine signals are transmitted more slowly than paracrine signals because
A. the ligands are transported through the bloodstream and travel greater distances.
B. the target and signaling cells are close together.
C. the ligands are degraded rapidly.
D. the ligands don't bind to carrier proteins during transport.
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What is the advantage of a signal transduction cascade?
A. The receptor/ligand becomes the transcription factor and affects gene expression directly.
B. Activation of molecules by phosphorylation allow for amplification of the signal as well as multiple responses to the signal.
C. It allows the signal to be active for a very long time.
D. It utilizes only tyrosine kinase receptors.
Which of the following occurs during transduction?
A. The ligand binds to receptor proteins.
B. The final protein activated affects gene expression.
C. A phosphorylation cascade utilizes kinase proteins to pass on the message.
D. The receptor molecule undergoes a conformational change releasing a second messenger.
G-linked proteins
A. activate a second messenger.
B. activate for a long term signal.
C. can be activated by any ligand.
D. form GTP as a product.
Which are the stages of cell signaling in the correct order?
A. reception > transduction > response
B. transduction > response > signal
C. differentiation > expression > transduction
D. reception > expression > phosphorylation
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