B - Because an active cell can only work if it has a 3-Dimension structure.
Answer down below:
If a deer population starts eating all the plants in a specific area, the plants, of course will kill the plants. But also, once all the plants will run out, all the organisms and deer will eventually die out.
The porcupine is a rodent with an unusual trait. Porcupines have sharp spines or quills that help protect it against its predators. This trait is different from other rodents because of its needle like quills. This animal is also similar to that of a hedgehogs.
I believe that what is meant with the phrase "older explanation" is none other that superstition. Therefore, I will give you one superstitious belief which is now explained by science.
In Southeast Asia, people used to believe that St. Elmo's fire appears in remote areas because a bloody battle occured in that place leaving disembodied souls of the dead wandering there in the night and even in sunshine!
For generations, many people believed that this is a fact and some even say that these apparitions are diabolical or demonic in nature. So often, caution is advised to people whenever a ball of fire appears out in the open.
However, recent breakthroughs in the 21st century helped scientists to explain this mysterious phenomena. They found out that St. Elmo's fire is actually plasma, nothing special. Now, plasma is considered one of the states of matter! But mind you, it still does not explain why St. Elmo's fire seems to have a mind of its own!
Sea snails help to keep the algae's population from growing to high. And the algae provides the sea snails with energy from the snails eating it as a food source.
