|
Author Question: Replication of previous research must include ________ variables. a) operationally define b) ... (Read 39 times) |
To prove that stomach ulcers were caused by bacteria and not by stress, a researcher consumed an entire laboratory beaker full of bacterial culture. After this, he did indeed develop stomach ulcers, and won the Nobel Prize for his discovery.
Not getting enough sleep can greatly weaken the immune system. Lack of sleep makes you more likely to catch a cold, or more difficult to fight off an infection.
In 1885, the Lloyd Manufacturing Company of Albany, New York, promoted and sold "Cocaine Toothache Drops" at 15 cents per bottle! In 1914, the Harrison Narcotic Act brought the sale and distribution of this drug under federal control.
Prostaglandins were first isolated from human semen in Sweden in the 1930s. They were so named because the researcher thought that they came from the prostate gland. In fact, prostaglandins exist and are synthesized in almost every cell of the body.
Between 1999 and 2012, American adults with high total cholesterol decreased from 18.3% to 12.9%