The answer is A. small nutrients
MRNA is needed in the cells because it directs the synthesis of proteins which is found in the cytoplasm. It is a molecule that carries the message contained within DNA to the ribosome. The Proteins are assembled on the ribosomes using the mRNA nucleotide sequence as a guide.
Answer:
Explanation:
During exhalation, the diaphragm also relaxes, moving higher into the thoracic cavity. This increases the pressure within the thoracic cavity relative to the environment. Air rushes out of the lungs due to the pressure gradient between the thoracic cavity and the atmosphere.
The oxygen cycle can be found in all but the geosphere. There's oxygen in the atmosphere, so it has to be there, and the biosphere includes living things, which breathe oxygen, and water (hydrosphere) is made up of partly hydrogen, so there has to be oxygen there as well.