It allows scientists to explore new explanations for observations.
Answer:
<h2>A</h2>
Explanation:
1. Nucleus is a ball like structure which is found in the center of the cell only in eukaryotic cell, true nucleus is absent in prokaryotes.
2. Nucleus contains nucleic acid and is have double membrane which contain pores though which transport of molecules occurs.
3. DNA replication , transcription and RNA splicing occur in the nucleus.
Both lipids and carbohydrates are important in animal cells because store energy. The main biological functions of lipids include storing energy, signaling, and acting as structural components of cell membranes. Carbohydrates on the other hand have six major functions in the body; including providing energy and regulation of blood glucose, sparing the use of proteins for energy, breakdown of fatty acids and preventing ketosis.
The widespread, large scale, worlddwide burning of enormous quantities of fossil fuels for their energy, such as coal, oil, and natural gas, could do that, if it ever began and became popular.
Oh, wait ! That"s what we've been doing, for a couple of centuries now !
