Learners examine the location, structure, and function of the unipolar and multipolar neurons.

Learners examine the structure and function of skin including the production of melanin.

This animated object illustrates the events leading to the migration of phagocytes into areas of tissue damage and/or bacterial presence. Learners view bacterial cell phagocytosis, its subsequent enzymatic digestion, and exocytosis.

Learners follow the steps for reducing all of the elements of a complex circuit to a single current source and a single source resistance to create a simple circuit. Several examples are given for dc circuits. The conversion between Thevenin and Norton is also presented.

In this learning activity you'll explore the effect of connecting voltage sources in series to increase voltage applied to a load.

This interactive object is designed to help learners memorize schematic symbols used in hydraulic diagrams. Learners quiz themselves using electronic flashcards.

Learners examine the differences and similarities between hydraulic and pneumatic systems.

In this learning activity you'll determine the measurement to be made and the accuracy required.

In this screencast, students read about the stages of microbial dental plaque formation and the time it takes for each stage to occur.

Learners develop 3D visualization skills by examining front, side, and top orthographic views of objects. Using this information, students select the corresponding isometric view of each object.

In this lesson on atomic structure, learners examine how the binding energy of electrons affects light production in certain phosphors used in x-rays.

In this screencast, learners review the parts of the gastrointestinal system and then check their knowledge in a matching exercise.

In this learning activity you'll examine how routers transfer data between local area networks and the Internet.

In this learning activity you'll review the six different ways in which electricity is produced: chemical, friction, heat, light, magnetism, and pressure.

Learners study the interaction between the conductors of the stator and the armature inside a DC motor, which causes the shaft to rotate. A short quiz completes the activity.

Students analyze the eight single variable Boolean theorems and their expressions.

Introduction to selecting the proper punch and die for air bending or bottoming when forming on a press brake. Includes charts and methods for selection.

In this interactive object, learners read how to determine the force created by a hydraulic cylinder during extension and retraction. A brief quiz completes the activity.

In this animated activity, learners study how the magnetic field of an armature can distort the DC motor's main magnetic field. A brief quiz completes the object.

Learners examine the ways in which a motor starter circuit is protected by a main circuit breaker and overload heaters when there is excessive current.

Students complete 10 practice problems. These deal with the determination of series current, zener current, and load current, and if the zener diode is operating in the breakdown region.

In this interactive object, learners sort veterinary antiparasitic medications into categories.

In this learning activity you'll examine how computers operate in a peer-to-peer network operating system.

In this video, you'll review how every protein molecule of an organism is synthesized.

In this screencast, learners will match the muscle names to their corresponding locations in the human body.