Answer:
Miasma theory was replaced because John Snow collected data that showed that germs cause disease.
Explanation:
The theory of miasma was proposed in the past when some scientists —like doctors Thomas Sydenham and Giovanni Maria Lancisi— thought that disease was the product of emanations originated by the decomposition of organic matter. This theory was based on the fact that diseases predominated in places with poor hygienic conditions.
John Snow, an english physician, was one of the main contributors to the <u>microbial theory of disease</u>. In 1854, while a cholera epidemic was occurring, he collected data and organized it statistically and then concluded that the disease was caused by germs present in drinking water. This <u>data was contrary to the miasma theory, which would eventually be displaced by the microbial theory of the disease</u>.
Answer:
Blood is carried away from the heart by arteries. Blood that is rich in oxygen. Blood that is low in oxygen is returned to the heart by veins. there is more pressure in arteries than in veins.
Answer:
Oxygen levels stay above 15 percent starting 200 million years ago
Explanation:
Atmospheric oxygen levels are related to the evolution on Earth and changes in geochemical cycles that involve climate variations.
The presence of O
2 and evolution of oxygen gave new opportunities to the life on Earth. Oxygen levels in atmosphere have fluctuated between 15% and 35% of atmospheric volume, since the start of the Cambrian period.
So, form the starting 200 million years ago, oxygen level stay above 15 percent and the correct option is "B".
Answer:
Explanation:
shrimp will have difficulty finding food and by time they disappear
