Exercise reduces stress by _?
a. increasing endorphins and reducing levels of stress hormones.
b. providing a therapeutic way to reduce or eliminate pain.
c. expanding aerobic capacity.
d. suppressing endocrine function.

The skin includes multiples layers. which of the following is not one of the layers of the skin?

The following statement about pathogens are true except for one, which statement is not true? a. pathogens belong in the human body b. pathogens can cause infectious diseases c. some pathogens can be classified as animals d. pathogens can multiply inside a host organism

Why do rna viruses appear to have higher rates of mutation? a) rna nucleotides are more unstable than dna nucleotides.b) replication of their genomes does not involve proofreading.c) rna viruses can incorporate a variety of nonstandard bases.d) rna viruses are more sensitive to mutagens.