Are changes to the order of nucleotides in a segment of dna that codes for a protein.
proto-oncogenes
tumor suppressor genes
gene mutations
negative regulators

Gene mutations

Explanation:

Gene mutations are changes that happen within the structure of DNA, the hereditary material of life. Gene mutations occur by changes in the order of nucleotides in a DNA segment that encodes a protein.

Gene mutations are punctual and may originate through the addition, substitution or loss of nitrogenous bases in a portion of the DNA molecule, which causes a change in protein coding. A classic example of gene mutation is that which occurs in sickle cell anemia, where the deformation of the sickle-shaped red blood cell comes from the exchange of the glutamic amino acid by the hemoglobin-forming valine, which causes a clustering of this protein. In addition to altering the morphology of red blood cells, once the red blood cells are grouped, they block blood vessels, reducing tissue oxygenation and, consequently, causing the death of the individual.

the supermassive black hole is in the middle of the galaxy.

it has to be understood that the sea water contains a huge amount of sodium and chlorine ions and if they enter the cell of the atlantic cod fish, the cell will shrivel and the fish will die. to avoid such a condition, the fish uses active transport for the purpose of removing the ions against the gradient.

explanation:

the atlantic cod is not a maritime osmoconformer. its native application of salts is less than that of the seawater it lives in. it is continually falling water from the gills to the ocean via osmosis.

countering that, the fish is going to be swallowing seawater. but since its internal collection of salts is lower than seawater, the fish will want to go free of excess salt, and since that's going upon a gradient, then active transport, requiring energy, must be used to pump out the salt. much marine fish use the organs to filter out the salt and these fish discharge very straight urine.