True or false. vigorous exercise should privide a significant challenge to your cardiovascular system?

At what age does trust usually begin to develop? a. 25 weeks b. 20 weeks c. 15 weeks d. 10 weeks

How does the endocrine system affect the body's functions? o o o o it secretes enzymes directly into the bloodstream. it secretes hormones directly into the bloodstream. it secretes enzymes through ducts to the surface of organs. it secretes hormones through ducts to the surface of organs.

You should never drive a car if you are a.taking cold medication b. suffering from the flu c. drinking alcohol d. all the above