The lifetime of NO is 5 - 10 minutes.

a. True

b. False

Answer: False.

Explanation:

Nitric oxide (NO) is a signalling molecule synthesised by NO synthase which is a a transmitter in the nervous system. Once it is produced, it diffuses out of the cell and act on nearby cells.

NO have a life time of few seconds and it is extremely unstable and highly reactive, it action is restricted.

The blood vessels uses it to signal the surrounding smooth muscle to relax.