Answer:
El aparato circulatorio unidireccional transporta sangre a todas las partes del cuerpo. Este movimiento de la sangre dentro del cuerpo se denomina «circulación». Las arterias transportan sangre rica en oxígeno del corazón y las venas transportan sangre pobre en oxígeno al corazón.
Explanation:
Lipids are unique because, they are made from one carbon skeleton unlike the other macro molecules groups which are made from smaller building blocks.
With the exception of steroid hormones, lipids are generally hydrophobic. Also lipids are relative small molecules when compare in size with other macromolecules.