Answer:
4. The suspected causative agent must be isolated from the diseased host and grown in pure culture
Explanation:
Robert Koch (1843-1910) was one of the most important bacteriologists of all time. Famous for discovering the tuberculosis bacillus (precisely on March 24, such as today, in 1882), he also discovered the cholera bacillus and is considered the founder of bacteriology. He worked on the isolation of infectious agents and reinfections from pure cultures, experiences from which he established the "Koch Postulates".
These postulates have been taken as a reference that describes the etiology of all the causative agents of an infectious disease, although they were originally used to describe only the tuberculosis bacillus. They are the following:
1- The agent must be present in each case of the disease and absent in the healthy.
2- The agent should not appear in other diseases.
3- The agent must be isolated in a pure culture from the lesions of the disease.
4- The agent has to cause the disease in an animal that can be inoculated
The question that could be investigated through scientific research is B. Does a newly synthesized chemical reduce bacteria? The answer is B. Because the other questions aren’t science questions. They are bias.
The federal government regulates and controls the economy through numerous laws affecting economic activity.
I hope that answers your question.
The poles never get any direct sunlight.
They both get the same amount of sunlight.
- Because they receive no direct sunshine, the Arctic (North Pole) and Antarctic (South Pole) are both chilly.
- Even at the height of summer, the Sun is low on the horizon. The Sun doesn't rise at all for several months during the winter since it is so deep below the horizon hence poles don't have equal amounts of sunlight and darkness.
- The poles receive less energy and heat from the sun because of the tilt of the earth and its orbit around the sun. There are just two polar seasons as a result: summer and winter.
- The tilt of the Earth's axis causes the Poles to experience around six months of day and six months of night.
- Due to this tilt, each Pole spends roughly six months angled both toward and away from the Sun. The North Pole experiences six months of nonstop daylight when it is inclined toward the Sun.
- In the winter, the Sun sets for extended periods of time since it is so deep below the horizon. Therefore, the days are chilly and dark, much like the nights. The South Pole and North Pole receive the same amount of sunshine despite being "polar opposites."
learn more about poles here: brainly.com/question/1776073
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Surface water always flows downhill. The answer is A.downhill