Group of tissues performing a specific task is known as organ and group of organs performing a specific task is organ system.
Answer: Armored fish
Explanation:
The earliest known fossil vertebrates were heavily armored fish discovered fish in rocks from the Ordovician period.
The fossils shows the path from the early aquatic life to the vertebrates, vertebrates to mammals.
The fossils shows that it is vertebrate and are the oldest known fossil ever known. The fossils of the animals and plants helps to known the behavior of the past time and based on that research and study is done.
the answer is B.extinction can be related to a failure to adapt to changes in the environment.
<span>Glucose which can also be fats from excess carbohydrates. </span>
Carbohydrates actually get stored in the form of long polymers of glucose molecules or as glycogen starch. They provide energy to the animals for performing their daily duties. Carbohydrates are generally considered the fuel for all organisms, and without this most animals would become sloth and would be unable to perform the regular jobs. Carbohydrates are actually very easy to metabolise and hence generate quick energy.<span>
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