|
|
Hyperthyroidism leads to an increased rate of metabolism and affects about 1% of women but only 0.1% of men. For most people, this increased metabolic rate causes the thyroid gland to become enlarged (known as a goiter).
Vaccines cause herd immunity. If the majority of people in a community have been vaccinated against a disease, an unvaccinated person is less likely to get the disease since others are less likely to become sick from it and spread the disease.
Liver spots have nothing whatsoever to do with the liver. They are a type of freckles commonly seen in older adults who have been out in the sun without sufficient sunscreen.
There are more nerve cells in one human brain than there are stars in the Milky Way.
When Gabriel Fahrenheit invented the first mercury thermometer, he called "zero degrees" the lowest temperature he was able to attain with a mixture of ice and salt. For the upper point of his scale, he used 96°, which he measured as normal human body temperature (we know it to be 98.6° today because of more accurate thermometers).
![Cystostomy. An artificial opening is made through the urinary bladder wall during this procedure. As](https://biology-forums.com/gallery/47/medium_14755_26_10_12_5_21_05_96681734.jpeg)
![Immunization with a vaccine. A healthcare professional is injecting a vaccine into the patient’s arm](https://biology-forums.com/gallery/47/medium_14755_11_11_12_7_20_13_10048217.jpeg)