Cells are the basic building blocks of all living things. The human body is composed of trillions of cells. They provide structure for the body, take in nutrients from food, convert those nutrients into energy, and carry out specialized functions. ... Cells have many parts, each with a different function.
Las células son los componentes básicos de todos los seres vivos. El cuerpo humano está compuesto por billones de células. Proporcionan estructura al cuerpo, ingieren nutrientes de los alimentos, convierten esos nutrientes en energía y realizan funciones especializadas. ... Las celdas tienen muchas partes, cada una con una función diferente.
Nucleotides are joined together by covalent bonds between the phosphate group of one nucleotide and the third carbon atom of the pentose sugar in the next nucleotide.