Answer:
One band of light density and one band of heavy density.
Explanation:
According to conservative model of replication, the original strands do not separate from each other during replication. Hence, after replication the old strands are together and the new strands are together.
Here, cells were grown in 14N medium first so 14N was used for DNA replication and all DNA molecules had 14N. When the cells were transferred to 15N medium, only 15N was available for replication process. New DNA molecules would be synthesised using 15N (15N15N) and old DNA molecules have 14N (14N14N). Hence, in density gradient one band will be of light density (14N14N) and one band will be of heavy density (15N15N).
Predation
It can be explained in that way or also called Predatory/prey relationships.
Parasitism is when one is benefited and the other harmed (ie leech and human)
Commensalism is when one is benefited and the other not affected (Tree frog and rainforest tree)
Mutualism is when both are benefited (Bee eats honey and Flower is pollinated).
Answer:
B. They have a single small nucleus.
Explanation:
The presence of large nucleus is a characteristic feature of cells that frequently undergo cell division. Cancer cells are characterized by uncontrolled continuous cell division even when the new cells are not required by the body.
This leads to the formation of benign or metastatic tumors. To undergo continuous cell division, the cancer cells have a large nucleus. The nucleus of the cancer cells is mostly hyperchromatic and distinct due to higher nuclear to cytoplasmic ratio. It allows these cells to exhibit the uncontrolled cell division.