Answer:
D. Mass extinction events separate the three eras from each other
Explanation:
The Phanerozoic is an eon, thus it is representative of the largest unit of geological time. It is further divided into three eras. The three eras of the Phanerozoic are the Paleozoic, Mesozoic, and Cenozoic. These three eras have been divided on the basis of mass extinction events. The Paleozoic ends with the mass extinction at the end of the Permian period, which is also the largest mass extinction ever, and it also marks the beginning of the Mesozoic. The Mesozoic ends with the mass extinction at the end of the Cretaceous period, occurring because of a large meteorite or comet impact, marking the beginning of the Cenozoic era. The Cenozoic era is still going, and even though there have been extinction throughout it, none of them has been of a scale big enough to be considered as a mass extinction, so until something like that happens, this era will continue to exist.
Presidential Reconstruction
In the spring of 1865, the Civil War came to an end, leaving over 620,000 dead and a devastating path of destruction throughout the south. The North now faced the task of reconstructing the ravaged and indignant Confederate states. There were many important questions that needed to be answered as the nation faced the challenges of peace:
<span>Who would direct the process of Reconstruction? The South itself, Congress, or the President?Should the Confederate leaders be tried for treason?How would the south, both physically and economically devastated, be rebuilt? And at whose expense?How would the south be readmitted and reintegrated into the Union?<span>What should be done with over four million freed slaves? Were they to be given land, social equality, education, and voting rights?</span></span>
Answer:
ecosystem
Explanation:
The level of organization shown in the example is "ecosystem" because the example represnts interaction between two different population with acorns on the land.
Ecosystem is defined as the interaction of groups of organisms in biological domain with abiotic enviornment.
The example, groups of organisms include "squirrels and birds" and abiotic enviornment include "acorns" or "nuts".
Hence, the correct option is "ecosystem".
Answer:
False.
Explanation:
SCN9A gene may be defined as a type of transcription factor responsible for the regulation of the voltage gated sodium channels. These genes are mainly expressed in nociceptive or pain receptor.
The mutation in SCN9A may disrupt the functioning of voltage gated sodium channels and not related with voltage gated potassium channels. The person is not able to feel the pain due to mutation on SCN9A gene.
Thus, the correct answer is option (b).
