|
|
Many medications that are used to treat infertility are injected subcutaneously. This is easy to do using the anterior abdomen as the site of injection but avoiding the area directly around the belly button.
Sperm cells are so tiny that 400 to 500 million (400,000,000–500,000,000) of them fit onto 1 tsp.
Thyroid conditions may make getting pregnant impossible.
Ether was used widely for surgeries but became less popular because of its flammability and its tendency to cause vomiting. In England, it was quickly replaced by chloroform, but this agent caused many deaths and lost popularity.
The term bacteria was devised in the 19th century by German biologist Ferdinand Cohn. He based it on the Greek word "bakterion" meaning a small rod or staff. Cohn is considered to be the father of modern bacteriology.
![Variation in the rate of evolution as a function of the strength of selection, assuming genetic drif](https://biology-forums.com/gallery/47/medium_33_31_08_11_2_12_19_16211335.jpeg)
![Aneurysm. Photograph of the aorta, the large blood vessel arising from the heart, with a large bulge](https://biology-forums.com/gallery/47/medium_14755_11_11_12_7_14_25_100201378.jpeg)