In the following video Paul Andersen explains how the dissolution of a solute in a solution can be explained as a reversible reaction. Bonds in the solid solute are broken and the ions are dissolved in a solution. The Ksp (or solubility product constant) can be used to explain the solubility of various salts. [7:06]

In the following video Paul Andersen explains how light that is perfectly reflected creates specular reflection. The angle of the incident ray is equal to the angle of the reflected ray. Specular reflection is also known as mirror-like reflection. If the reflecting surface is irregular it will create diffuse, rather than specular reflection. [4:33]

In this video Paul Andersen explains how the boundary between the system and environment is chosen to simplify analysis of a physics problem. [3:13]

The following video narrated by Paul Andersen explains how systems are two or more objects that interact with one another. If a system has no relevant internal structure it can be treated as an object. The conservation laws apply to energy, charge and momentum in a system. [2:29]

In the following video Paul Andersen explains how objects in contact with varying temperatures will eventually reach thermal equilibrium with equal temperatures. The amount of thermal energy transferred is related to the mass and temperature of the objects since momentum is transferred and conserved along the margin. [3:48]

In the following video Paul Andersen explains how the total energy of a system is the combination of kinetic, potential and internal energy of the objects. He then shows you how to calculate the kinetic energy, gravitational potential energy, and elastic potential energy of objects within a system. Over time the total energy of the system will change due to changes in position and frictional effects. [6:14]

Paul Andersen explains how the vector sum of forces can be used to identify the net force on an object. The net force can be used to determine the overall acceleration of the object using Newton's Second Law. [6:54]

Paul Andersen explains how water quality can be degraded by pollutants. Wastewater is the main source of water pollution and can be measured using the BOD (biochemical oxygen demand). Dead zones, cultural eutrophication, disease, and other pollutants are included. A 'Water Pollution Concept Map' is also available for download. [9:07]

Paul Andersen explains how water is unequally distributed around the globe through the hydrologic cycles. Seawater is everywhere but is not useful without costly desalination. Freshwater is divided between surface water and groundwater but must me stored and moved for domestic, industrial, and agricultural uses. [11:38]

Paul Andersen explains how the energy of a wave if directly related to the amplitude of a wave. The wave energy of a sound wave is the volume of the wave. [3:39]

In the following video the wave model of the electron can be used to explain the Bohr model. Electrons are found in certain orbits because they interfere with themselves and create standing waves. When the wavelengths don't match up with a whole integer they will create destructive interference. [4:02]

In the following video Paul Andersen explains how light can be treated as both a particle and a wave. Physicists use scale to determine which model to use when studying light. When the wavelength of light is equivalent to the size of the object a wave model is used. [3:34]

In this video, Paul Andersen describes both weather and climate. Weather refers to the day-to-day conditions on the Earth's surface, including temperature, wind, humidity, air pressure, and precipitation. Climate means the long-term conditions on the Earth's surface. Both climate and weather are determined by sunlight, water, landforms, and life forms. [7:47]

In the following video Paul Andersen explains how the kinetic energy gained by an object is equivalent to the work done on the object. The force on the object must act parallel or antiparallel to the motion of the object to do work. [8:12]

In the following video Paul Andersen explains how the mechanical energy added or removed from a system results from work. For work to occur a force must act parallel to the displacement of the system. Since work and energy are equivalent the work-energy theorem allows of for calculating the work as the change in kinetic energy. [7:01]

In the following video Paul Andersen explains how buffer solutions maintain pH in a solution. A buffer solution is made up of a weak acid and its conjugate base. As strong acids or bases are added the pH remains stable. A good buffer solution has a pKa value equivalent to the pH and equal amounts of the weak acid and the conjugate base. [5:57]

In this lesson, students will explore the structures of generalized and specialized cells like brain cells, by engaging with the Looking Inside: Cells VR app, then applying that knowledge to a neuron activity worksheet. Students will then connect structure and function in a neuron by exploring neural networks and communication through the Build Your Network digital interactive. This lesson plan is 1 of 2 that are meant to be taught in sequence, as students apply the knowledge from lesson 1 to lesson 2.

Estimated time required: 1-2 class periods.

Technology required for this lesson: Laptop/Desktop, VR Headset (Optional).

This lesson is designed to introduce students to the unique structure of neurons and how they communicate with each other through cell structure review via the Looking Inside: Cells app and a hands-on neurotransmission game. This lesson plan is 2 of 2 that are meant to be taught in sequence, as students apply the knowledge from lesson 1 to lesson 2.

Estimated time required: 1-2 class periods.

Technology required for this lesson: Laptop/Desktop, VR Headset (Optional).

Video tutorial breaks down photosynthesis into two stages: light dependent reactions and the Calvin cycle. [4:47]

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