What functional groups do the acidic side chains share in common? What functional groups do the basic side chains share in common?

What is thought to have caused the mass extinction at the end of the cretaceous period?

1. which of the following is correct regarding opiates/opioids: a. they all have a natural component as a starting pointb. they have low addiction possibilitiesc. methadone binds to some of the same receptorsd. a and care correcte. all are correct

Which of the following are the functions of the integumentary system? yadda-yadda, the 1st answer is the brainliest. : )