Question

In heart cells, which one serves as a second messenger, speeding up muscle cell contraction in response to adrenaline _____________.

• A. cAMP
• B. cGMP
• C. GTP
• D. ATP
• E. AMP

Answer 1

The correct option is A cAMP

A. cAMP
EXPLANATION: It is a second messenger. The full form of cAMP is cyclic adenosine monophosphate. It is used for intracellular signal transduction, like transferring the effects of hormones like adrenaline, glucagon into the cells. It also helps in the activation of protein kinases. cAMP controls beating frequency, force of contraction and relaxation of heart and helps in speeding up muscle cell contraction in the response to adrenaline hormone.