GCSE Biology - Fossils & Extinction (2026/27 exams) скачать в хорошем качестве

GCSE Biology - Fossils & Extinction (2026/27 exams)

⭐️ Check out our website https://www.cognito.org/ ⭐️ ** WHAT'S COVERED ** 1. Introduction to Fossils Definition: Remains or traces of long-dead organisms. Examples: Rock skeletons, impressions, preserved organisms. 2. Importance of Studying Fossils Understanding extinct organisms (most life is extinct). Providing evidence for evolution by showing changes over time. 3. How Fossils are Formed Gradual replacement by minerals (mineralisation of hard parts like bone, teeth, shells). Casts and impressions (moulds left by organisms or footprints). Preservation without decay (in amber, tar pits, ice/glaciers, peat bogs due to lack of oxygen, moisture, or suitable temperature/pH). 4. The Fossil Record Age of the earliest fossils found. Why the fossil record is incomplete (early life soft-bodied, geological destruction of older fossils). 5. Extinction Definition: When no individuals of a species remain alive. Reasons for extinction: Rapid environmental changes (habitat loss, climate change), new predators (including human hunting), new diseases, competition from new species, catastrophic events (e.g., asteroid impacts). ** CHAPTERS ** 0:00 What are Fossils? 0:24 Why Study Fossils? 1:01 Formation by Gradual Replacement by Minerals 1:35 Formation of Casts & Impressions 2:08 Formation by Preservation 2:41 The Incomplete Fossil Record 3:25 Extinction: Definition 3:34 Reasons for Extinction ** PLAYLISTS **    • GCSE Maths (9-1)      • GCSE Biology (9-1)      • GCSE Chemistry (9-1)      • GCSE Physics (9-1)      • A-Level Biology   #GCSE #Biology #study #revision #school #exam #AQA #OCR #Edexcel #IGCSE