Answer:
Single-cell organisms
Explanation:
In 1735, Linnaeus introduced a classification system with only two kingdoms: animals and plants. Linnaeus published this system for naming, ranking, and classifying organisms in the book "Systema Naturae". In the epoch that Linnaeus created this system, single-cell organisms such as bacteria and protists were almost unknown. In 1866, E. Haeckel added a category including both bacteria and protozoa, thereby adding a category formed by single-cell organisms (different from animals and plants). During the 1900-1920 period, bacteria were classified as a separated kingdom named 'prokaryotes'. The current three-domain classification system was introduced by C. Woese in 1990. In this system, all forms of life are divided into three different domains: archaea, bacteria, and eukaryote domains (this last composed of protists, fungi, plants and animals).
Answer:
vaccination
Explanation:
The vaccination has been one of the most revolutionary inventions in the medical field. This invention helped protect people from numerous diseases, some being totally neutralized, while some having only minor effects on the human body. The vaccination basically is a way of enhancing the immune system of the body by injecting in it a weakened form of the pathogen. In this way, the weakened form of the pathogen is not capable to harm the body, and the body is not fighting against it, but instead the pathogen becomes part of the body and its defense mechanism, so when the pathogen strikes, the body has a counter attack and defeats it.
Answer:
defines the problem to be explored
Because Chlorophyll is found in The chloroplasts that appears throughout the plant's cells hoped it helped
Fossil fuels are considered a nonrenewable energy source because once fossil fuels are used, they are gone. So, the correct option is A.
<h3>What do you mean by Nonrenewable energy?</h3>
Nonrenewable energy may be defined as that energy that once consumed can not be replenished for millions of years.
Fossil fuels are examples of nonrenewable energy resources. The formation of fossil fuels may take over millions of years. This fuel is made naturally by the decomposition of dead and decayed organic living matter.
Therefore, the correct option for this question is A.
To learn more about Fossil fuels, refer to the link:
brainly.com/question/79954
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