The best answer for the blood vessels' valves would be these are veins that would then help in preventing the back flow of blood because the walls have small muscle to pump the blood back to the heart.Hope this is the answer.
Answer
Cortisol
Explanation:
Cortisol or stress hormone is a steroid hormone produced in the adrenal gland( Cortex) .A spike in the levels of this hormone suppresses Serotonin levels in the blood. Serotonin is a neuro- transmitter in the brain for mood regulation and balance of memory., good sleep sexual function.
A spike in the levels in the cortisol level in the blood brings a corresponding decrease in the levels of Serotonin,which therefore leads to mood swings depression and insomnia,anxiety by reducing the receptors for serotonin,and therefore disrupting Endorphins levels in the brain.
Exercises decreases the levels of cortisol in the blood,and boost the levels of serotonin therefore boosting the amount of serotonin in the blood ,thus promoting good mood, reduce depression etc
There are a wide range of database components including tables for the data, a query language that retrieves specific data elements, and forms for entering or displaying data. There are also reporting tools and customized page views of data.
A. Build stamina. It is doing a low intensity high duration exercise.
