From which of the following does the basic structure of hair and nails form?
a. sweat
c. collagen
b. melanin
d. keratin

What is the term for all traits passed biologically from parent to child.

Mario was conducting research regarding the treatment of aids victims using stem cells. he found a source that was written recently and the author was known. unfortunately, he could not determine if it had been peer reviewed.

In which way does nicotine cause addiction? by stimulating the brain’s pleasure center by increasing blood-sugar levels by decreasing dopamine levels by reducing depression and anxiety