<span>The correct answer is A, B and D. Biogeochemical cycles are central to the ecology of earth system. They make the essentail elements accessible and available for the organisms, and maintain their levels, so that the ecology is ot disrupted. The elements move through abiotic and biotic factors, in these cycles, and a state of equilibrium is maintained n the ecosystem. The carbon dioxide levels are responsible fr the temperature of the earth. If Carbon cycles would not have existed, then there would have been a disruption in maintaining the global temperature. Biogeochemical cycles basically continuously recycles the essential materials, for sustaining the life-forms.</span>
The correct answer to this is:
“Astrocytes”
Astrocytes also called star cells due to their shape are the
most abundant glial cells in the brain. Extensions from these cells encase
capillaries and offer extra control over which materials enter or leave the
intercellular fluid of the CNS thus acting like a permeability membrane.
Answer:
B) Natural selection favored rabbits that were resistant to the virus
Explanation:
Most likely, virus resistance occurred over time, as a consequence of mutation. Individuals that carried the resistance mutation become favourable by natural selection.
Natural selection is evolutionary mechanism which favours traits of an organism that help him survive and reproduce (increase organism's fitness). In the example above, resistant rabbits that survived had the favorable trait (resistance) by natural selection.
I would have to say A. ribosomes are known to break and release their digestive juices into the cell upon cell death. thus killing them