The starch and water molecules in potato cells are stored in what organelle? OPTIONS:
- mitochondrion
- nucleus
- ribosome
- vacuole
A: vacuole

Which body system is most affected by a disease that causes the bones to become weak and brittle? OPTIONS:
- excretory
- muscular
- skeletal
- nervous
A: skeletal

Which best describes the role of the esophagus in digestion? OPTIONS:
- It releases acid and mixes food.
- It aids in absorption of nutrients from food.
- It carries food from the mouth to the stomach.
- It carries food from the stomach to the intestines.
A: It carries food from the mouth to the stomach.

Which of the following allows a cell to become specialized? OPTIONS:
- location of the cell in the body
- function of the cell in the body
- different patterns of gene expression
- different combinations of genes in the nucleus
A:
different patterns of gene expression