The awnser is b there is a mutation in the gene
It is extremely useful for geologists, because most specimens of a given mineral are very close to the same hardness. ... So, we can conclude that not all the rocks are hard, and the hardness of rocks depends on how the atoms of the rock's minerals are bound to each other and how they are arranged.
Vascular tissue in plants is made of two specialized conducting tissues: xylem, which conducts water, and phloem, which conducts sugars and other organic compounds. A single vascular bundle always contains both xylem and phloem tissues.
It is more precise to illustrate biosphere as the global ecosystem rather than the global community as it just comprises all the living things in a specific region regarding their distinct species. However, when one talks about the ecosystem, one automatically incorporates both the nonliving and living things like water, soil, etc. So, it is more precise in saying the global ecosystem, when one is talking about the Earth biosphere.
As marine ecosystems constitute over 70 percent of the surface of the Earth, the influence of these ecosystems on the global food web is impressive. The oceans are an essential source of oxygen for the planet and are efficient in the recovery and room for carbon dioxide. The marine classes offer essential ecosystem services like the preparation of drugs, food, and livelihoods. They also support recreational projects and tourism all around the globe.
