DNA is the main type of genetic material found in a cell. In addition, it is found in the nucleus of the cell, so (D) is correct. DNA in the nucleus is used in replication (through mitosis and meiosis) via daughter cells to continue cell growth.
Single celled organisms such as amoebas, especially those that live in fresh water, continually gain water from their surrounding environment by osmosis. This water is pumped into a contractile vacuole which fills with fluid and periodically fuses with the cell membrane, releasing its contents to the exterior. Thus the amount of water actively transported out of the cell is equal to the amount of water entering the cell due to osmosis and there are no variations in the tonicity of the cell. This is homeostasis at a simple level. Without the contractile vacuole, the amoeba would continue to absorb water until its cytoplasmic contents were diluted to such an extent that metabolism no longer occurred and it would die.
Answer:
Shape and structure.
Explanation:
The difference in shape and structure of these pictures is responsible for the difference from each other. The organisms present in these pictures are different in their size, shape and composition of their body. Some are small and some are large, some are living while the others are non-living, some are very hard whereas the others are soft and fleshy. So the organisms present in these samples are different from each other in a variety of ways i.e. size, shape and body structure.