Answer:
Same DNA being used to make different proteins
Explanation:
Cells of all living organisms contain the genetic material called DNA. One of the characteristics of multicellular cells is the ability of their cell to DIFFERENTIATE i.e. form specialized cells during division.
However, it is worthy to note that all cells possess the same DNA but some of the genes contained are expressed into proteins while others are not. This leads to why cells that contain similar DNA make different proteins and perform differently.
In this case, cardiac (heart) cells and brain cells contain the same DNA but due to the expression of some genes and repression of others, they are able to differentiate into different cells.
