Cells are the smallest unit of life. This is true.
Cells are important to the structure and function of living things. This is true.
All organisms are made of multiple cells. This is false, because there are many single celled organisms like bacteria.
Cells come in different shapes and sizes. This is true, as there are cells with a variety of shape and size (round shaped cocci and the elongated and flat bacillus). There are cells from squid's nervous system, called the neurons, that are comparatively very large in size than the vast majority of the other cells.
the part of the flower with pollen in it is the stamen
Answer: Keystone species
Explanation: A keystone species is a species which occupied a niche so central in the ecosystem that it has a disproportionately large effect on its environment and other species in it.
The coral's function in its ecosystem is so vital that if you were to remove it, the entire community would be drastically altered beyond recognition.
The coral serves as the base structure of its ecosystem.
That is to say that many corals are hermatypic(they form reefs). This reef serves as the environmental structure of the Coral's ecosystem. Built in and around it is a very biodiverse biotic environment. The coral not only serves as a hiding place and habitat for many marine organisms including fish, clams, lobsters, etc. It serves as resting place for larger animals like turtles and also serves as hunting sites for other animal species.
The most common way of determining a keystone species, is to see what happens when that species is removed from the ecosystem. Coral have shown to be so central to their ecosystem that the bleaching of coral reefs due to tourism and climate change causes a massive loss to biodiversity. And this is quite significant as reefs are the most biodiverse marine habitats.
I think the answer is cellular
