Chromosome Numbers Before and After Mitosis and Meiosis (UPDATED)

Confused about how chromosome numbers change before and after mitosis and meiosis? This Amoeba Sisters UPDATED video breaks down chromosome vs chromatid and shows how to count chromosomes and how they change in cell division, all organized in clear, easy-to-understand tables. This video also goes into some of the nuances in terms like centromere, haploid, and diploid which can be common sources of confusion. Note: This video is an update of an older Amoeba Sisters video titled "Chromosome Numbers During Division: Demystified!" https://youtu.be/gcz1FOWw0Cg?si=FpwIhIQG-XWINDjS --------------- TABLE OF CONTENTS: 00:00 Intro 1:05 Chromosome vs Chromatid 2:40 Interphase 3:21 Centromere 4:15 Chromosome Numbers Before and After Mitosis 5:11 Chromosome Numbers Before and After Meiosis 5:56 Haploid and Diploid 7:22 Both Completed Tables --------------- FACTUAL REFERENCES: Alberts, Bruce, et al. Molecular Biology of the Cell. 4th ed., New York, Garland, 2002. Clark, Mary Ann, et al. “The Cell Cycle - Biology 2e - OpenStax.” Openstax.org, 28 Mar. 2018, openstax.org/books/biology-2e/pages/10-2-the-cell-cycle. Urry, Lisa A, et al. Campbell Biology. 11th ed., New York, NY, Pearson Education, Inc, 2017. FURTHER READING: 1. Chromosome, Chromatid 🔑 ULTIMATELY, a KEY CONCEPT from video is that when not attached, a chromatid can be referred to as a chromosome. Video notes that some sources will refer to a chromosome as having "one chromatid" or "two chromatids" while others use the word "chromatid" only when referring to one of the attached sister chromatids. Either way, the key concept remains the same. 2. Centromere 🔑The centromere can be described either by its visible constricted region or at the molecular level that focuses on the centromeric DNA and the proteins that bind there. Example of focus on classic, constricted region definition: -https://www.genome.gov/genetics-glossary/Centromere -Biology, 6th Edition, Campbell and Reece -https://openstax.org/books/biology-2e/pages/10-key-terms Example of focus on molecular definition (emphasizing on each chromatid): -https://pmc.ncbi.nlm.nih.gov/articles/PMC6465287/ -Campbell Biology, 11th Edition, Urry, Cain, Wasserman, Minorsky, Reece (NOTE: This is a more updated version than the 6th edition listed above that utilizes classic definition) Learn more about the centromere here: https://pmc.ncbi.nlm.nih.gov/articles/PMC3687001/ 3. Learn more about karyotypes in our karyotype video: https://youtu.be/mBq1ULWJp_M?si=A8wCKo2PcCFjrHbp ----------------------------------------------- The Amoeba Sisters videos demystify science with humor and relevance. The videos center on Pinky's certification and experience in teaching biology at the high school level. Learn more about our videos here: https://www.amoebasisters.com/our-videos ⭐ Our Linktree: https://linktr.ee/amoebasisters ❤️ Support Us? https://www.amoebasisters.com/support-us 🗂️ Resources that complement our videos! https://docs.google.com/spreadsheets/d/1b3kmAzFEjWgoMKCrkeNCKFYunWk04IuLY93jI4OY0gY/pubhtml Biology Video Playlist: https://www.youtube.com/playlist?list=PLwL0Myd7Dk1F0iQPGrjehze3eDpco1eVz TIPS FOR VIEWING EDU YOUTUBE VIDEOS: Want to learn tips for viewing edu YouTube videos including changing the speed, language, viewing the transcript, etc? https://www.amoebasisters.com/pinkys-ed-tech-favorites/10-youtube-tips-from-an-edu-youtuber-duo MUSIC: Intro music purchased and licensed to Amoeba Sisters LLC. End music in this video is listed free to use/no attribution required from the YouTube audio library. TRANSLATIONS: https://www.amoebasisters.com/pinkys-ed-tech-favorites/community-contributed-subtitles