Question

nematodes have successfully adapted to nearly every from marine (salt) to fresh water, soils, from the polar regions to the tropics, as well as the highest to the lowest of elevations. they are found in every part of the earths (crust and upper mantle) and they represent of all animals on the ocean floor. due to their numerical dominance, often exceeding a million individuals per square meter and accounting for about of all individual animals on earth, their diversity of lifecycles, and their presence at various trophic levels point to an important role in many ecosystems. they have also been shown to play roles in polar ecosystems. crucial ecosystem lithosphere 80% 90%

Explanation:

To solve this fill - in - the - blank problem, we analyze each blank based on the context and the provided word options:

First Blank

The sentence is about the environments that nematodes have adapted to. The word "ecosystem" fits here as it refers to a biological community and its environment. So the first blank should be filled with "ecosystem".

Second Blank

The sentence mentions the Earth's crust and upper mantle. The term "lithosphere" is defined as the rigid outer part of the earth, consisting of the crust and upper mantle. So the second blank is "lithosphere".

Third Blank

We are talking about the proportion of nematodes among all animals on the ocean floor. From the options, "90%" is a reasonable proportion. So the third blank is "90%".

Fourth Blank

This is about the proportion of nematodes among all individual animals on earth. "80%" is a suitable value from the given options. So the fourth blank is "80%".

Fifth Blank

The sentence is about the roles nematodes play in polar ecosystems. The word "crucial" means very important, which fits the context of their role in ecosystems. So the fifth blank is "crucial".

Answer:

1. ecosystem
2. lithosphere
3. 90%
4. 80%
5. crucial