What causes the acidic environment of the vagina?

During penile erection, the chemicals __ and ___ are released from motor neurons to cause smooth muscle in arterioles to relax and increase blood flow to the penis.  Abbreviations are not accepted.

The final three questions show graphs depicting results of hypothetical factorial designs. For each one, identify the effects that look like they would (probably) be statistically significant.

Based on the description above, it sounds like the scale of measurement for task performance is:

Which of the following effects appear to be present based on this graph? [Select all that apply.]

Provide THREE typical symptoms that are observed with BPH (benign prostatic hyperplasia).

What happens during the menstrual phase and why?

The gallbladder stores ______ and concentrates it by _____ absorption when the _____ is closed.

(Note: this is a posterior view) Identify the labeled structure A. Identify the labeled structure B.    

Some lipid digestion products can be directly absorbed into villi blood capillaries and include and .