This "Cellular Respiration" learning object is the from the Sumanas resource series. Sumanas offers a robust selection of content and services that are directed at enhancing the learning experience.

Paul Andersen explains how a respirometer can be used to measure the respiration rate in peas, germinating peas and the worm. KOH is used to solidify CO2 produced by a respiring organism.

In this podcast Paul Andersen explains how cells differentiate to become tissue specific. He also explains the role of transcription factors in gene regulation. The location of a cell within the blastula ultimately determines its fate. The SrY gene is an important external stimuli in human development.

Paul Andersen explains how variation is created within a cell. He starts by showing how molecular variation can increase fitness at the local level. He explains how an additional chlorophyll molecule allows plants to absorb more light from the sun.

Find out how the your body uses special cells that are central to the brain (inside the brain) to sense levels of CO2 and pH. Rishi is a pediatric infectious disease physician and works at Khan Academy. These videos do not provide medical advice and are for informational purposes only. The videos are not intended to be a substitute for professional medical advice, diagnosis or treatment. Always seek the advice of a qualified health provider with any questions you may have regarding a medical condition. Never disregard professional medical advice or delay in seeking it because of something you have read or seen in any Khan Academy video.

The video resource "Central Nervous System: Crash Course A&P #11" is included in the "Anatomy & Physiology " course from the resources series of "Crash Course". Crash Course is a educational video series from John and Hank Green.

In this TED Talk video, Capt. Charles Moore discusses the problem of plastic debris in our seas. The resource, "Charles Moore TEDTalk Video" included in "Lesson 4 Plastic Indestructible Waste" is a part of "Unit 02 The Human Footprint" included in Energy & Sustainability ES - Course 2

Paul Andersen shows you how to calculate the chi-squared value to test your null hypothesis. He explains the importance of the critical value and defines the degrees of freedom. He also leaves you with a problem related to the animal behavior lab. This analysis is required in the AP Biology classroom.

The video resource "Chordates - CrashCourse Biology #24" is included in the "Biology" course from the resources series of "Crash Course". Crash Course is a educational video series from John and Hank Green.

Paul Andersen explains aspects of genetics that were not covered by Gregor Mendel. He begins with the following topics; incomplete dominance, codominance, epistasis, multiple alleles, and multiple genes. He then explains how linked genes were discovered by Thomas Hunt Morgan and Alfred Sturtevant. He also discusses sex-linked traits.

Paul Andersen describes genetics at the chromosomal level.  He begins with a simple monohybrid cross as viewed through Mendelian genetics and then shows how genes are distributed through meiosis to possible gametes.  This is following by a dihybrid cross and a cross that shows gene linkage.

Hank takes us on a trip around the body - we follow the circulatory and respiratory systems as they deliver oxygen and remove carbon dioxide from cells, and help make it possible for our bodies to function.

The video resource "Circulatory & Respiratory Systems - CrashCourse Biology #27" is included in the "Biology" course from the resources series of "Crash Course". Crash Course is a educational video series from John and Hank Green.

Paul Andersen surveys the circulatory system in humans. He begins with a short discussion of open and closed circulatory systems and 2, 3, and 4-chambered hearts. He describes the movement of blood through the human heart and the blood vessels. He discusses the major components of blood and the cause of a heart attack.

Paul Andersen shows you how to use a sphygmomanometer to measure the systolic and diastolic blood pressure. Then he the describes the elements of the laboratory portion. The temperature is gradually lowered and the respiration rate of a goldfish is measured.