GENETICS AND EVOLUTION
INHERITANCE AND VARIATION
Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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The DNA is the same but each cell contains different genes
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The DNA is the same but different genes are turned on in each cell
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Each cell has its own unique DNA
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The DNA is different, but each cell contains the same genes
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Detailed explanation-1: -Compared to DNA in other cells, neurons have more, less and rearranged DNA. And these changes accumulate over time.
Detailed explanation-2: -Although all cells contain the same DNA sequence, muscle cells are different from nerve cells and other types of cells because of the different genes that are turned on in these cells and the different RNAs and proteins produced.
Detailed explanation-3: -These cells are different because they use the same set of genes differently. So even though each of our cells has the same 20, 000 or so genes, each cell can select which ones it wants to “turn on” and which ones it wants to keep “turned off”.
Detailed explanation-4: -The muscle cell and nerve cell inherit different DNA sequences. Transcription of different genes leads to the synthesis of different proteins in the two cell types. The chromosomal DNA is rearranged and mutated so that the cell can become a muscle cell instead of a nerve cell.