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Gastrointestinal system physiology
Anatomy & PhysiologyCollege | Online class
Do you live to eat, or eat to live? Folks fall on both sides of this question, but who can deny the powerful role that food and water play in our everyday lives. If we were cars, food and water...
GDP: Measuring national income
Online classEconomics can some times get confusing because one person’s expenditure is another person’s income which can then be used for expenditure and on and on and on. Seems very circular. It is. This...
Gene regulation
GeneticsCollege | Online class
You have tens of thousands of genes in your genome. Does that mean your cells express all of those genes, all the time? Not by a long shot! Even an organism as simple as a bacterium must carefully...
Geometric constructions
Online classWith just a compass and a straightedge (or virtual versions of them), you’ll be amazed by how many geometric shapes you can construct perfectly. This tutorial gets you started with the building...
Geometric optics
Online classIn these videos and articles you’ll learn how to determine the angle of reflected light and the definition of specular and diffuse reflection. You’ll also learn how to use Snell’s law to determine...
Global contemporary: 1980-present
Contemporary ArtCollege | Online class
Global contemporary art is characterized by a transcendence of traditional conceptions of art and is supported by technological developments and global awareness. Digital technology in particular...
Global modernisms in the 21st century
Online classCulture, like capitalism, is increasingly global. Artists work internationally and no single city is now the center of the art world. Istanbul, Beijing, Bogotá, Beirut, Lagos, and São Paulo all...
Global prehistory: 30,000-500 B.C.E.
History7th - College | Online class
Human expression existed across the globe before the written record. While prehistoric art of Europe has been the focus of many introductions to the history of art, very early art is found...
GMAT
GMAT PreparationCollege | Online class
Sal works through the 249 problem solving questions in chapter 5 of the the 11th edition of the official GMAC GMAT Review (ISBN Number: 0-9765709-0-4 published in 2005)
Graphing lines and slope
Graphs7th - College | Online class
How can we communicate exactly where something is in two dimensions? Who was this Descartes character? In this tutorial, we cover the basics of the coordinate plane. We then delve into graphing...
Graphs of trigonometric functions
TrigonometryHigh School - College | Online class
Sal draws the graph of the tangent function based on the unit circle definition of the function.
Greek art
Art HistoryHigh School - College | Online class
Rio 2016, London 2012, Beijing 2008, Olympia 776 B.C.E. find out how the ancient pan-Hellenic games inspired our modern Olympiad. Then learn to identify the classical orders and you will never look...
Green's, Stokes', and the divergence theorems
Online classGreen’s theorem (videos) It is sometimes easier to take a double integral (a particular double integral as we’ll see) over a region and sometimes easier to take a line integral around the boundary....
Health and medicine
Anatomy & PhysiologyHigh School - College | Online class
No organ quite symbolizes love like the heart. One reason may be that your heart helps you live, by moving ~5 liters (1.3 gallons) of blood through almost 100,000 kilometers (62,000 miles) of blood...
Hematologic system diseases
DiseaseCollege | Online class
Blood is incredibly important in combating disease and the healing process after an injury. It acts as a highway for medicine, stops bleeding, fights infections, controls cells from multiplying too...
High Renaissance in Florence and Rome
Online classAs the Humanism of the Early Renaissance develops, a problem arises. How can an artist create figures that are at once an accurate naturalistic rendering of the human body in space while also...
Home-made robots
RoboticsHigh School - College | Online class
Mrs. Rowhani’s third graders learn about matter and energy by building a Spout bot with Khan Academy. Special thanks to: Santa Rita’s volunteer parents, Ka…
Hour of Code
Computer Programming4th - College | Online class
Learn how to program drawings using JavaScript by designing your very own snowman. Try it on your own or with your class!