Question 1.1. a person’s skin cells and heart cells both have a complete copy of all of the person’s chromosomes. each cell, however, makes different types of proteins to perform its function. what is the source of the instructions from which all of the proteins are made?
genes

mitochondria

gametes

cell membrane

After reading the text represented above, it has become clear for me that the source of the instructions from which all of the proteins are made is  genes, because, according to the general knowledge of DNA, instructions are stored in the genetic material of a cell which means that they are made od genes, so, answer is obviously A.
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