a. Competition: Humans compete with all organisms for space.
b. Parasitism: Humans have many parasites: head lice, ticks, tapeworms, etc.
c. Mutualism: We have mutualistic relationships with all domesticated plants/animals.
d. Commensalism: Pigeons thrive in metropolitan ecosystems without really
affecting humans (except for being mildly disgusting).
The correct answer is a nutrient runoff.
Nutrient runoff is a major reason for eutrophication of surface waters, in which extra amount of nutrients, generally phosphorus or nitrogen, instigate growth of algae. Sources of nutrient pollution involve surface runoff from pastures and farm fields, emissions from combustion, and discharges from septic tanks.
I would say energy myself, and this is because energy plays a key role in all of these. With trophic levels energy is being transferred amongst the levels. Food chain's is a map of how the energy is passed along the chain. Food web is a web of how energy is transferred, and this is why I would say energy is a keyword.
You did not included your list of selections. Some general properties ascribed to DNA are storage and expression of information and variables through mutations. Replication, Transcription, Translation and Mutagenesis are the major functions of DNA in a cell. DNA nucleotides contain deoxyribose. DNA is double-stranded in the conservative mode, the original double Helix remains a complete unit and the new DNA double Helix is produced as a single unit. In the double=stranded DNA, Hydrogen bonds hold one complimentary strand to the other.
Hope this helps, I love Science.
Answer:
False!!!!!!!!!!
Explanation:
FALSE
Intermediates of nucleotide degradation that results from the breakdown of nucleotide does not just end in the bloodstream but undergoes certain salvage pathways before being converted to complete nucleotides
