The answer is skin cells. Other cells, like nerve and brain cells, divide much less often.
The correct answer is d. morula.
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A morula is a stage in early development, formed 3–4 days after fertilization. It is a 16-cell mass which forms a solid ball contained within the zona pellucida. A morula develops into a blastocyst.</span>
A lit candle needs to draw oxygen from the air in order to continue burning. If you limit the amount of air available, the candle's flame eventually goes out once it uses up all the oxygen. Lit candles in smaller jar stop burning first because the oxygen trapped in the jar are fewer than the ones in bigger jars.
Absence of true roots stems and leaves