Biology Regents Practice Exam

Which cellular change could be inherited by the next generation?

1. A change in ribosomes in the pancreas of a squirrel

2. The deletion of a single DNA base in a sperm cell of a trout

3. A decrease in the size of a vacuole in a rose leaf cell

4. The transfer of a piece of a chromosome in the skin cell of a raccoon

The correct answer is: The deletion of a single DNA base in a sperm cell of a trout

The deletion of a single DNA base in a sperm cell of a trout could be inherited by the next generation because it involves a change in the genetic material that affects the gametes, which are the cells involved in reproduction. When a sperm cell that has undergone a genetic mutation fertilizes an egg cell, the resulting offspring will inherit that mutation, thus passing it on to future generations. In contrast, changes in cells that are not involved in reproduction, such as those found in the pancreas of a squirrel, the vacuoles in a rose leaf cell, or skin cells of a raccoon, do not affect the genetic information that is transmitted to offspring. Such changes are typically somatic—occurring in body cells that do not contribute to the genetic makeup of the next generation—and therefore cannot be inherited. Only alterations in germ cells (sperm and egg) can be passed on, making the deletion of a DNA base in a sperm cell significant for inheritance.