In sexual reproduction, chromosomes can sometimes swap sections during the process of meiosis (cell division), thereby creating new genetic combinations and thus more genetic variation. Although DNA replication is tightly regulated and remarkably accurate, errors do occur and result in mutations, which are also a source of genetic variation. Environmental factors can also cause mutations in genes, and viable mutations are inherited. Khan Academy is a nonprofit organization with the mission of providing a free, world-class education for anyone, anywhere. We offer quizzes, questions, instructional videos, and articles on a range of academic subjects, including math, biology, chemistry, physics, history, economics, finance, grammar, preschool learning, and more. We provide teachers with tools and data so they can help their students develop the skills, habits, and mindsets for success in school and beyond. Khan Academy has been translated into dozens of languages, and 15 million people around the globe learn on Khan Academy every month. As a 501(c)(3) nonprofit organization, we would love your help! Donate or volunteer today! Donate here: https://www.khanacademy.org/donate Volunteer here: https://www.khanacademy.org/contribute ... https://www.youtube.com/watch?v=D0XYWKm_LoM Note: All Khan Academy content is available for free at (www.khanacademy.org)

Determining bias of sample statistics based on approximate sampling distributions example. View more lessons or practice this subject at http://www.khanacademy.org/math/ap-statistics/sampling-distribution-ap/what-is-sampling-distribution/v/sample-statistic-bias-worked-example?utm_source=youtube&utm_medium=desc&utm_campaign=apstatistics AP Statistics on Khan Academy: Meet one of our writers for AP¨_ Statistics, Jeff. A former high school teacher for 10 years in Kalamazoo, Michigan, Jeff taught Algebra 1, Geometry, Algebra 2, Introductory Statistics, and AP¨_ Statistics. Today he's hard at work creating new exercises and articles for AP¨_ Statistics. Khan Academy is a nonprofit organization with the mission of providing a free, world-class education for anyone, anywhere. We offer quizzes, questions, instructional videos, and articles on a range of academic subjects, including math, biology, chemistry, physics, history, economics, finance, grammar, preschool learning, and more. We provide teachers with tools and data so they can help their students develop the skills, habits, and mindsets for success in school and beyond. Khan Academy has been translated into dozens of languages, and 15 million people around the globe learn on Khan Academy every month. As a 501(c)(3) nonprofit organization, we would love your help! Donate or volunteer today! Donate here: https://www.khanacademy.org/donate?utm_source=youtube&utm_medium=desc ... https://www.youtube.com/watch?v=SRwMfEmKx3A Note: All Khan Academy content is available for free at (www.khanacademy.org)

Understand 3/2 on the number line by thinking about it as a mixed number. Practice this lesson yourself on KhanAcademy.org right now: https://www.khanacademy.org/math/pre-algebra/fractions-pre-alg/dividing-fractions-pre-alg/e/understanding-fractions-as-division?utm_source=YT&utm_medium=Desc&utm_campaign=PreAlgebra Watch the next lesson: https://www.khanacademy.org/math/pre-algebra/fractions-pre-alg/dividing-fractions-pre-alg/v/dividing-a-whole-number-by-a-fraction-word-problem?utm_source=YT&utm_medium=Desc&utm_campaign=PreAlgebra Missed the previous lesson? https://www.khanacademy.org/math/pre-algebra/fractions-pre-alg/dividing-fractions-pre-alg/v/creating-a-fraction-through-division-of-whole-numbers?utm_source=YT&utm_medium=Desc&utm_campaign=PreAlgebra Pre-Algebra on Khan Academy: No way, this isn't your run of the mill arithmetic. This is Pre-algebra. You're about to play with the professionals. Think of pre-algebra as a runway. You're the airplane and algebra is your sunny vacation destination. Without the runway you're not going anywhere. Seriously, the foundation for all higher mathematics is laid with many of the concepts that we will introduce to you here: negative numbers, absolute value, factors, multiples, decimals, and fractions to name a few. So buckle up and move your seat into the upright position. We're about to take off! ... https://www.youtube.com/watch?v=V8C15AfL6Gk Note: All Khan Academy content is available for free at (www.khanacademy.org)

Sal finds the 4th term in the sequence whose recursive formula is a(1)=-⅛, a(i)=2a(i-1). Watch the next lesson: https://www.khanacademy.org/math/high-school-math/math1/math1-sequences/math1-constructing-geometric-sequences/v/explicit-and-recursive-formulas-for-geometric-sequences?utm_source=YT&utm_medium=Desc&utm_campaign=highschoolmath Missed the previous lesson? https://www.khanacademy.org/math/high-school-math/math1/math1-sequences/math1-introduction-to-geometric-sequences/v/using-explicit-formulas-of-geometric-sequences?utm_source=YT&utm_medium=Desc&utm_campaign=highschoolmath High School Math on Khan Academy: Did you realize that the word "algebra" comes from Arabic (just like "algorithm" and "al jazeera" and "Aladdin")? And what is so great about algebra anyway? This tutorial doesn't explore algebra so much as it introduces the history and ideas that underpin it. About Khan Academy: Khan Academy is a nonprofit with a mission to provide a free, world-class education for anyone, anywhere. We believe learners of all ages should have unlimited access to free educational content they can master at their own pace. We use intelligent software, deep data analytics and intuitive user interfaces to help students and teachers around the world. Our resources cover preschool through early college education, including math, biology, chemistry, physics, economics, finance, history, grammar and more. We offer free personalized SAT test prep in partnership with the test developer, the College Board. Khan Academy has been translated into dozens of languages, and 100 million people use our platform worldwide every year. For more information, visit www.khanacademy.org, join us on Facebook or follow us on Twitter at @khanacademy. And remember, you can learn anything. ... https://www.youtube.com/watch?v=RkJBZALhXRA Note: All Khan Academy content is available for free at (www.khanacademy.org)