https://www.khanacademy.org/science/revision-term-1-od-grade-9-life-science/x26da6cb4aecf5718:week-1/x26da6cb4aecf5718:diversity-in-living-organisms/v/systems-of-classification 2023-03-03T23:12:40.787581739Z Systems of Classification From grouping living beings based on the number of legs to introducing new domains, classification has been one rollercoaster of a ride. In this video, we take a walk down the "history" lane and find out how biological classification has changed over the last few centuries. Sulagna Das video https://cdn.kastatic.org/googleusercontent/ZCdwTudJg6e6n-P2gsaUborP4izvMsGo71pvEVlX9dNYWcLXcP7VHkWpn2grt4TUP1KoJLQP9NswyHBuBLSFTBw Systems of Classification From grouping living beings based on the number of legs to introducing new domains, classification has been one rollercoaster of a ride. In this video, we take a walk down the "history" lane and find out how biological classification has changed over the last few centuries. https://cdn.kastatic.org/ka-youtube-converted/mrheet-2osg.mp4/mrheet-2osg.mp4 500 Diversity in living organisms https://www.khanacademy.org/science/revision-term-1-od-grade-9-life-science/x26da6cb4aecf5718:week-1/x26da6cb4aecf5718:diversity-in-living-organisms/e/biological-classification 2026-03-06T17:50:38.494926415Z Biological classification The exercise explores the hierarchy of classification groups, the relationship between evolution and classification, and binomial nomenclature. Moumita Sen exercise https://www.khanacademy.org/science/revision-term-1-od-grade-9-life-science/x26da6cb4aecf5718:week-1/x26da6cb4aecf5718:diversity-in-living-organisms/e/monera-and-protista 2026-04-08T00:54:09.631945657Z Monera, Protista, and Fungi This exercise is about the kingdoms Monera and Protista, Nivedhitha Suresh exercise https://www.khanacademy.org/science/revision-term-1-od-grade-9-life-science/x26da6cb4aecf5718:week-1/x26da6cb4aecf5718:diversity-in-living-organisms/v/plant-kingdom 2023-03-03T23:12:40.787581739Z Plant Kingdom In this video, we explore an overview of Kingdom Plantae. We talk about plants and the various types of plants within this complex kingdom. Sulagna Das video https://cdn.kastatic.org/googleusercontent/ZCdwTudJg6e6n-P2gsaUborP4izvMsGo71pvEVlX9dNYWcLXcP7VHkWpn2grt4TUP1KoJLQP9NswyHBuBLSFTBw Plant Kingdom In this video, we explore an overview of Kingdom Plantae. We talk about plants and the various types of plants within this complex kingdom. https://cdn.kastatic.org/ka-youtube-converted/VfKGU4ZaO8k.mp4/VfKGU4ZaO8k.mp4 595 Diversity in living organisms https://www.khanacademy.org/science/revision-term-1-od-grade-9-life-science/x26da6cb4aecf5718:week-1/x26da6cb4aecf5718:diversity-in-living-organisms/e/lower-plants 2026-03-06T17:50:38.494926415Z Lower Plants This exercise is about Thallophyta, Bryophyta, and Pteridophyta Nivedhitha Suresh exercise https://www.khanacademy.org/science/revision-term-1-od-grade-9-life-science/x26da6cb4aecf5718:week-1/x26da6cb4aecf5718:diversity-in-living-organisms/e/higher-plants 2026-03-06T17:50:38.494926415Z Higher Plants This exercise is on gymnosperms and angiosperms. Nivedhitha exercise https://www.khanacademy.org/science/revision-term-1-ka-biology-grade-11/x1474e0ca4285b2f5:week-1/x1474e0ca4285b2f5:animal-kingdom/v/classification-of-animals 2023-04-14T21:01:17.579162109Z Classification of animals Here we delve into some criteria used to classify animals - levels of organization, symmetry, the number of tissue layers, and coelom, and have a quick overview of the different animal phyla. Moumita Sen video https://cdn.kastatic.org/googleusercontent/ZCdwTudJg6e6n-P2gsaUborP4izvMsGo71pvEVlX9dNYWcLXcP7VHkWpn2grt4TUP1KoJLQP9NswyHBuBLSFTBw Classification of animals Here we delve into some criteria used to classify animals - levels of organization, symmetry, the number of tissue layers, and coelom, and have a quick overview of the different animal phyla. https://cdn.kastatic.org/ka-youtube-converted/01T15fMv5Uo.mp4/01T15fMv5Uo.mp4 925 Diversity in living organisms https://www.khanacademy.org/science/revision-term-1-ka-biology-grade-11/x1474e0ca4285b2f5:week-1/x1474e0ca4285b2f5:plant-kingdom/v/pteridophytes 2023-02-04T23:01:02.978880581Z Pteridophytes In this video, we talk all about pteridophytes: the first plants ever to have vascular tissues! We take a closer look at their life cycle and find out why they are the “in-between version” of bryophytes and higher plants. Sulagna Das video https://cdn.kastatic.org/googleusercontent/ZCdwTudJg6e6n-P2gsaUborP4izvMsGo71pvEVlX9dNYWcLXcP7VHkWpn2grt4TUP1KoJLQP9NswyHBuBLSFTBw Pteridophytes In this video, we talk all about pteridophytes: the first plants ever to have vascular tissues! We take a closer look at their life cycle and find out why they are the “in-between version” of bryophytes and higher plants. https://cdn.kastatic.org/ka-youtube-converted/sCLTyZHbVpk.mp4/sCLTyZHbVpk.mp4 322 Diversity in living organisms https://www.khanacademy.org/science/revision-term-1-od-grade-9-life-science/x26da6cb4aecf5718:week-1/x26da6cb4aecf5718:diversity-in-living-organisms/v/gymnosperms-the-male-cone 2023-04-06T11:41:49.823875081Z Gymnosperms - the male cone Let's look at the structure of the male cone of gymnosperms and learn about the strobilus, the microsporophyll, the microsporangium, and the male gametophyte. Moumita Sen video https://cdn.kastatic.org/googleusercontent/ZCdwTudJg6e6n-P2gsaUborP4izvMsGo71pvEVlX9dNYWcLXcP7VHkWpn2grt4TUP1KoJLQP9NswyHBuBLSFTBw Gymnosperms - the male cone Let's look at the structure of the male cone of gymnosperms and learn about the strobilus, the microsporophyll, the microsporangium, and the male gametophyte. https://cdn.kastatic.org/ka-youtube-converted/793KjbILDfM.mp4/793KjbILDfM.mp4 275 Diversity in living organisms https://www.khanacademy.org/science/revision-term-1-od-grade-9-life-science/x26da6cb4aecf5718:week-1/x26da6cb4aecf5718:diversity-in-living-organisms/e/simple-animals-class-ix 2026-03-06T17:50:38.494926415Z Simple Animals This exercise is about Porifera and Cnidaria. Nivedhitha exercise https://www.khanacademy.org/science/revision-term-1-od-grade-9-life-science/x26da6cb4aecf5718:week-1/x26da6cb4aecf5718:diversity-in-living-organisms/e/non-chordates-i 2025-02-11T06:12:20.85923236Z Non chordates - I This exercise is about animal phyla Platyhelminthes, Nematoheleinthes, and Annelida. Nivedhitha exercise https://www.khanacademy.org/science/revision-term-1-od-grade-9-life-science/x26da6cb4aecf5718:week-1/x26da6cb4aecf5718:diversity-in-living-organisms/e/chordata-od 2026-03-06T17:50:38.494926415Z Chordata This exercise is about the features of the phylum Chordata and the subphyla Urochordata, Cephalochordata and Vertebrata. Nivedhitha exercise https://www.khanacademy.org/science/revision-term-1-od-grade-9-life-science/x26da6cb4aecf5718:week-1/x26da6cb4aecf5718:diversity-in-living-organisms/e/vertebrata-i 2026-03-06T17:50:38.494926415Z Vertebrata - I This exercise is about the classes Cyclostomata, Pisces, and Amphibia. Nivedhitha exercise https://www.khanacademy.org/science/revision-term-1-od-grade-9-life-science/x26da6cb4aecf5718:week-1/x26da6cb4aecf5718:diversity-in-living-organisms/e/vertebrata-ii 2026-03-06T17:50:38.494926415Z Vertebrata - II This exercise is on the vertebrate classes Reptilia, Aves, and Mammalia. Nivedhitha exercise