On cold nights, a warm quilt is necessary.

In chemistry class, I learned about basic oxides.

In chemistry class, I learned about acidic oxides.

Bioweapons are a major threat to humanity.

In this experiment, we will use various inorganic compounds.

In this experiment, we will observe the reaction of organic compounds.

This structure has existed for centuries.

Protists are being studied in a branch of biology.

Arthropods are a large group of animals that include insects, spiders, shrimp, and crabs.

Carbohydrates are important as a source of energy.