HOSA Human Heredity Practice Test

Genes are located on chromosomes, which are structures that organize and package DNA within the cells. Each chromosome is made up of DNA tightly coiled around proteins called histones, which helps maintain the structure and regulates gene expression. In human cells, chromosomes are found in the nucleus, where they are housed in a protective environment that allows for the controlled access to the genetic material.

The total number of chromosomes is specific to the organism; humans typically have 23 pairs, totaling 46 chromosomes, which collectively carry the genes that dictate various traits and functions. Although mitochondria do contain some DNA, it is separate from the chromosomal DNA contained in the nucleus and primarily encodes genes necessary for mitochondrial function. The cell membrane, on the other hand, primarily serves as a barrier and communication interface for the cell rather than a location for genetic material.