Learners observe that the melting of a solid and the freezing of its liquid occur at the same temperature. The melting point is an intrinsic property and is used to identify a substance.

Learners read a brief description of the vertebral column and examine the distinctive features of the cervical, thoracic, and lumbar vertebrae.

In this animated object, learners examine the eight cranial bones, the fourteen facial bones, and the ribs.

Learners examine the meaning of theoretical yield, actual yield, and percent yield. They test their knowledge by solving two problems.

In this screencast, learners categorize different metabolic activities as catabolic or anabolic and follow a glucose molecule through the processes of glycolysis, aerobic respiration, and fermentation.

Vapor pressure is the pressure exerted by molecules in the gas phase in equilibrium with a liquid or a solid. Two examples are used to illustrate vapor pressure: the drying of clothes and the evaporation of ice.

Learners examine the lifecycle of basidiomycetes. Terminology and fungi examples are provided.

Boyle's Law states that gas volume varies inversely with the pressure at constant temperature and is described by the equation PV = constant. An example of a sample of gas at two conditions of P and V is used to illustrate the law.

Learners examine the function of the analog wattmeter to measure true power, how it is connected in a circuit, and how the internal components develop a measurement. A brief quiz completes the activity.

In this animated object, learners examine the different types of joints and their movements.

In this screencast, learners examine the function and location of the motor neurons and the damage that can result when they are injured.

Learners examine the method for calculating the atomic weight of copper from the natural percent composition of each of its two isotopes.

In this animated and interactive object, learners examine the properties of liquids, solids, and gases.

In this animated object, learners examine the formation of peptide bonds through dehydration synthesis.

In this interactive learning object, students read about the voltage and current parameters commonly found on a data sheet. A brief quiz completes the activity.

Learners match the names of parasitic organisms to the diseases they cause and the modes of transmission.

Learners examine the function and wiring of the sympathetic nervous system.

Chytrids, as members of this group are known, are found everywhere. In this animated learning object, students examine the role of chytrids and their impact on the environment.

In this interactive object, learners calculate formula and molecular weights by working through five examples and two problems.

In this animated and interactive object, learners examine the inverse proportionality of wavelength and frequency and their relationship to the speed of light.