Why do cells have to constantly produce ATP?

Idon’t understand this can someone give me the answer? you

After dinner with his brother, charles darwin looked through a book by thomas robert malthus, who believed that humanity, if unchecked, could double its population size in 25 years . why then , wasn't the earth overrun with humans at this point ? how does this relate to the stoning of the darwin's carriage?

Which best describes the chemical reaction taking place?