https://www.khanacademy.org/science/ncert-class-8-science/x55541eeaec8b3a9a:microorganisms-friend-and-foe/x55541eeaec8b3a9a:what-is-a-cell/v/cell-size-dubv 2025-05-29T08:44:44.739717086Z Cell size Let's think about the limiting factors of cell size. Focus on volume to surface area ratio. Dubverse video https://cdn.kastatic.org/googleusercontent/ZCdwTudJg6e6n-P2gsaUborP4izvMsGo71pvEVlX9dNYWcLXcP7VHkWpn2grt4TUP1KoJLQP9NswyHBuBLSFTBw Cell size Let's think about the limiting factors of cell size. Focus on volume to surface area ratio. https://cdn.kastatic.org/ka-youtube-converted/Bf7ipaOXMgU.mp4/Bf7ipaOXMgU.mp4 536 Introduction to cells https://www.khanacademy.org/science/ap-biology/cell-structure-and-function/cell-size/e/cell-size-exercise 2026-04-08T08:09:55.69362548Z Cell size Test your knowledge of cell size! Haider Ali Bhatti exercise https://www.khanacademy.org/science/revision-term-1-od-grade-9-life-science/x26da6cb4aecf5718:week-2/x26da6cb4aecf5718:introduction-to-cells/v/osmosis-in 2024-01-16T04:11:35.384208864Z Osmosis Let's explore what Osmosis is and how it works. Mahesh Shenoy video https://cdn.kastatic.org/googleusercontent/ZCdwTudJg6e6n-P2gsaUborP4izvMsGo71pvEVlX9dNYWcLXcP7VHkWpn2grt4TUP1KoJLQP9NswyHBuBLSFTBw Osmosis Let's explore what Osmosis is and how it works. https://cdn.kastatic.org/ka-youtube-converted/675-VDL9dwA.mp4/675-VDL9dwA.mp4 177 Introduction to cells https://www.khanacademy.org/science/revision-term-1-ka-science-grade-9/x07cce91f26fedd3c:week-2/x07cce91f26fedd3c:introduction-to-cells/v/hypotonic-isotonic-and-hypertonic 2025-06-10T19:04:14.612693506Z Hypotonic, Isotonic and Hypertonic Let's understand Hypotonic, Hypertonic and Isotonic solutions! Skyloom (Dubbing) video https://cdn.kastatic.org/googleusercontent/ZCdwTudJg6e6n-P2gsaUborP4izvMsGo71pvEVlX9dNYWcLXcP7VHkWpn2grt4TUP1KoJLQP9NswyHBuBLSFTBw Hypotonic, Isotonic and Hypertonic Let's understand Hypotonic, Hypertonic and Isotonic solutions! https://cdn.kastatic.org/ka-youtube-converted/eaMAppsuGOQ.mp4/eaMAppsuGOQ.mp4 382 Introduction to cells https://www.khanacademy.org/science/bridge-course-class-11th-biology/xfa1bbeaa3bc88e64:cells-and-tissues/xfa1bbeaa3bc88e64:cells/e/osmosis-and-diffusion 2026-03-06T17:50:38.494926415Z Osmosis and Diffusion Let's solve some questions! vibhor exercise https://www.khanacademy.org/science/revision-term-1-ka-science-grade-9/x07cce91f26fedd3c:week-2/x07cce91f26fedd3c:introduction-to-cells/v/prokaryotic-and-eukaryotic-cells-dubv 2025-05-29T08:44:44.739717086Z Prokaryotic and Eukaryotic cells Eukaryotic cells contain membrane-bound organelles (such as the nucleus and mitochondria), while prokaryotic cells do not. DNA in eukaryotic cells is found inside the nucleus, while DNA in prokaryotic cells is located in the cytoplasm. Eukaryotic cells are generally larger and more complex than prokaryotic cells. Eukaryotic organisms include animals, plants, fungi, and paramecia. Prokaryotic organisms include bacteria and archaea. Let's learn more about them in this video. Dubverse video https://cdn.kastatic.org/googleusercontent/ZCdwTudJg6e6n-P2gsaUborP4izvMsGo71pvEVlX9dNYWcLXcP7VHkWpn2grt4TUP1KoJLQP9NswyHBuBLSFTBw Prokaryotic and Eukaryotic cells Eukaryotic cells contain membrane-bound organelles (such as the nucleus and mitochondria), while prokaryotic cells do not. DNA in eukaryotic cells is found inside the nucleus, while DNA in prokaryotic cells is located in the cytoplasm. Eukaryotic cells are generally larger and more complex than prokaryotic cells. Eukaryotic organisms include animals, plants, fungi, and paramecia. Prokaryotic organisms include bacteria and archaea. Let's learn more about them in this video. https://cdn.kastatic.org/ka-youtube-converted/PaDQNDIkaWA.mp4/PaDQNDIkaWA.mp4 409 Introduction to cells https://www.khanacademy.org/science/mh-grade-8-science/x0f256b8de9c7cf34:cell-and-cell-organelles/x0f256b8de9c7cf34:cell-organelles/e/prokaryotic-and-eukaryotic-cells-1 2026-04-08T08:09:55.69362548Z Prokaryotic and eukaryotic cells Check your understanding of the differences between prokaryotic and eukaryotic cells. Moumita Sen exercise https://www.khanacademy.org/science/revision-term-1-tg-biology-class-9/x55ae3f7a2ac497cf:week-1/x55ae3f7a2ac497cf:cell-structure-and-function/v/overview-of-animal-and-plant-cells-dubv 2025-05-29T08:44:44.739717086Z Overview of animal and plant cells Animal and plant cells share common elements like plasma membranes, cytoskeletons, and mitochondria. However, they differ in certain aspects. For example, plant cells have a cell wall and a central vacuole, while animal cells contain centrosomes. The understanding of these cellular structures continues to evolve through ongoing research. Dubverse video https://cdn.kastatic.org/googleusercontent/ZCdwTudJg6e6n-P2gsaUborP4izvMsGo71pvEVlX9dNYWcLXcP7VHkWpn2grt4TUP1KoJLQP9NswyHBuBLSFTBw Overview of animal and plant cells Animal and plant cells share common elements like plasma membranes, cytoskeletons, and mitochondria. However, they differ in certain aspects. For example, plant cells have a cell wall and a central vacuole, while animal cells contain centrosomes. The understanding of these cellular structures continues to evolve through ongoing research. https://cdn.kastatic.org/ka-youtube-converted/xRvVAKmKZSs.mp4/xRvVAKmKZSs.mp4 521 Introduction to cells https://www.khanacademy.org/science/revision-term-1-ka-science-grade-9/x07cce91f26fedd3c:week-2/x07cce91f26fedd3c:introduction-to-cells/e/characteristics-of-the-cell 2026-03-06T17:50:38.494926415Z Characteristics of the cell Practice questions on the basic characteristics of cells. Moumita Sen exercise https://www.khanacademy.org/science/ms-biology/x0c5bb03129646fd6:cells-and-organisms/x0c5bb03129646fd6:cell-parts-and-functions/e/understand-cell-parts-and-functions 2026-04-02T04:15:35.616513959Z Understand: cell parts and functions Check your understanding of cell parts and functions in this set of free practice questions aligned to NGSS standards. Khan Academy exercise https://www.khanacademy.org/science/revision-term-1-ka-science-grade-9/x07cce91f26fedd3c:week-2/x07cce91f26fedd3c:introduction-to-cells/v/endomembrane-system-class-9 2023-01-06T23:01:02.201701884Z Endomembrane system Let's understand the “Endomembrane system” . Khadijatul Qubra video https://cdn.kastatic.org/googleusercontent/ZCdwTudJg6e6n-P2gsaUborP4izvMsGo71pvEVlX9dNYWcLXcP7VHkWpn2grt4TUP1KoJLQP9NswyHBuBLSFTBw Endomembrane system Let's understand the “Endomembrane system” . https://cdn.kastatic.org/ka-youtube-converted/9zMvku04wo8.mp4/9zMvku04wo8.mp4 828 Introduction to cells https://www.khanacademy.org/science/revision-term-1-ka-science-grade-9/x07cce91f26fedd3c:week-2/x07cce91f26fedd3c:introduction-to-cells/v/mitochondria-and-plastids 2023-01-12T07:05:48.839177327Z Mitochondria and plastids Let's look at the functions of mitochondria and plastids in a eukaryotic cell. Khadijatul Qubra video https://cdn.kastatic.org/googleusercontent/ZCdwTudJg6e6n-P2gsaUborP4izvMsGo71pvEVlX9dNYWcLXcP7VHkWpn2grt4TUP1KoJLQP9NswyHBuBLSFTBw Mitochondria and plastids Let's look at the functions of mitochondria and plastids in a eukaryotic cell. https://cdn.kastatic.org/ka-youtube-converted/eu5Azn23khc.mp4/eu5Azn23khc.mp4 731 Introduction to cells https://www.khanacademy.org/science/revision-term-1-ka-science-grade-9/x07cce91f26fedd3c:week-2/x07cce91f26fedd3c:introduction-to-cells/e/parts-of-the-cell-and-their-functions 2026-04-08T01:15:04.085520103Z Parts of the cell and their functions Let's revise the different parts of the cell, like the nucleus, Golgi apparatus, etc., and the roles they play in the cell. Moumita Sen exercise https://www.khanacademy.org/science/bridge-course-class-11th-biology/xfa1bbeaa3bc88e64:cells-and-tissues/xfa1bbeaa3bc88e64:cells/e/cell-division 2026-03-06T17:50:38.494926415Z Cell Division Let's solve some questions vibhor exercise