Name an organism that acts as secondary
consumer and a tertiary consumer.

When the bear eats salmon, the bear is functioning as a tertiary consumer (this is because salmon is a secondary consumer, since salmon eat herring that eat zooplankton that eat phytoplankton, that make their own energy from sunlight).

Explanation:

italy's population growth rate is almost at zero, the national statistics agency, istat, said on monday, mainly due to a dwindling birth rate.

the sugar-phosphate backbone forms the structural framework of nucleic acids, including dna and rna. this backbone is composed of alternating sugar and phosphate groups, and defines directionality of the molecule.