Answer:
1
Explanation:
the answer is the first one
There are number of endemic species, because island isolation promotes allopatric speciation and the latter occurs when species become separated from each other to the level that prevents genetic recombination.
I would say DNA needs to be in a double helix so it can be unraveled and duplicated during cell mitosis
<em><u>Answer:</u></em>
They generate chemical energy in the form of ATP.
<u><em>Explanation:</em></u>
Mitochondria are the powerhouses of the cell because they "burn" or break the chemical bonds of glucose to release energy to do work in a cell. This releases energy (ATP) for the cell. The more active a cell (such as a muscle cell), the more mitochondria it will have.
The correct answer is: introns
Processing of mRNA is process that occurs only in eukaryotic cells. After the transcription, newly formed mRNA molecule is called and it must be processed into a messenger RNA (mRNA). Processing includes:
• Addition of a 5' cap to the beginning of the RNA
• Polyadenilation- addition of a poly-A tail (tail of A nucleotides) to the end of the RNA
• Splicing- removal of introns and linking the exons
After these steps mRNA is mature and used for the further steps (e.g. translation).
Sometimes some genes are alternatively spliced.
