Biogeochemical cycles are crucial to ecosystem function because

The correct option is B.

Explanation:

The options attached to the question are given below:

A. They keep the planet warm enough for living things to survive

B. Nutrients and other life-sustaining molecules are in limited supply and must be continually recycled

C. Energy flows through ecosystems in one direction only and is eventually dissipated as heat

D. They remove poisons and keep them locked up in "sinks"

 Biogeochemical cycles refers to the pathways by which chemical substances move through the abiotic and biotic segments of the earth. The most important biogeochemical cycles include: carbon, nitrogen, phosphorus, oxygen and water cycles. Biogeochemical cycles transport and store important substances so that they can be available for the use of living organisms.  

Biogeochemical cycles are very crucial to living organisms because they help to recycle nutrients and other life sustaining molecules, which are in limited supply and which must be continuously recycled.

americans began to notice growing differences between the northern and southern sections of the country. there were more people living in cities in the north, which made it more urban. more people lived on farms in the south, which made it more rural. while many people were farmers in the northern states, there were now other ways to make a living, such as working in mechanical cotton gins factories manufacturing cloth, tools and other goods. people in the north supported high tariffs on goods imported from europe because the extra cost encouraged people to “buy american” instead. in the southern states, planters did not like tariffs because they sold most of their production to europe and bought their tools from there as well. southerners believed the protective tariff was something that only northern factory owners keep their profits high. so the southern politicians came up with an idea. they would opt out. they would simply ignore the protective tariff. it was ‘null and void’ in south carolina. the state would not collect the taxes on goods imported into south carolina, no matter what the president said they had to do. this decision led to the nullification crisis.

weathering - colorado river carves land in arizona to form the grand canyon. cracks form in a sandstone wall surrounding a house. a marble statue near the science museum is changing color due to rainfall

erosion - after a rainstorm, soil and rock piees litter the roadways. the sand dunes in the sahara desert are changing shape.

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