The answer to the question above is letter D. <span>Chromosomes found in the cell nucleus.</span>
In the cell nucleus, DNA is tightly packed into the
thread-like structure known as chromosomes. Every chromosome is made up of
tightly coiled DNA around proteins (histones) that support its structure.
Chromosomes are not visible when there is no cell division. It cannot be seen
in the cell’s nucleus nor under the finest microscope. They are only visible
when the cell is dividing and is apparently visible under a microscope.
Answer: c
Explanation: Plants and animals need nitrogen to make proteins but they cannot take it in from the air. Because nitrogen is unreactive as a gas, it has to be transformed into a new molecule. When bacteria in the soil takes nitrogen from the air, it becomes nitrates. Finally, it can move through the food chain in this form.
