Nucleotides
Nucleotide consists of 5 carbon sugar, a nitrogen base and a phosphate
Think where mitochondria are found in the greatest numbers - they are found (for example) in liver cells, kidney cells, muscle cells etc. These tissues carry out a lot of work and thus require lots of energy.
<span>Fat is a storage product that sits there until required but the thyroid does lots of work involved in metabolism and therefore requires plenty of energy.
This should help :)
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I would say the correct answer is "Care for their offspring"
