A-Level Biology - A-Level Biology - Non-random Sampling - Methods | Abiotic Factors & Distribution (2026/27 exams)

⭐️ Check out our website https://www.cognito.org/ ⭐️ *** WHAT'S COVERED *** 1. Differences between random and non-random sampling * How random sampling removes human bias from data collection * How non-random sampling selects areas based on specific criteria or patterns 2. Three main types of non-random sampling * Systematic sampling using regular intervals * Opportunistic sampling using conveniently available organisms * Stratified sampling dividing a population into distinct subgroups 3. Non-random sampling methods * Using line transects to record organisms that touch a line * Using continuous and interrupted belt transects with quadrats 4. Measuring abiotic factors and their effects * Identifying non-living components of an ecosystem like light, wind speed and humidity * Using tools like sensors and probes to detect environmental changes * Measuring the effect of abiotic factors on species distribution along an environmental gradient *** EXAM BOARD SPECIFIC INFO *** AQA - You don't need to know about the difference between belt and line transects, or the different types of non-random sampling OCR - You don't need to know about the difference between continuous and interrupted belt transects CIE - You don't need to know about the difference between continuous and interrupted belt transects, or the different types of non-random sampling *** CHAPTERS *** 0:00 Introduction to non-random sampling 0:28 Differences between random and non-random sampling 1:11 Systematic, opportunistic and stratified sampling 2:44 Line and belt transects methods 4:30 Measuring abiotic factors in ecosystems 5:25 Measuring the effect of abiotic factors on species distribution *** PLAYLISTS *** https://youtube.com/playlist?list=PLidqqIGKox7VzYfPIVt8T09xOLNcolCe4&si=8JmDajxjtba6rdc3 https://youtube.com/playlist?list=PLidqqIGKox7UZ3mWhbHv2aA_1vnbsfRPq&si=q3hEKdA4v7kbfwMe https://youtube.com/playlist?list=PLidqqIGKox7UTimdJ3eFcnt6xL9GUt2a6 https://youtube.com/playlist?list=PLidqqIGKox7XPh1QacLRiKto_UlnRIEVh&si=orIUwL3o2jOoiYjT https://youtube.com/playlist?list=PLidqqIGKox7X5UFT-expKIuR-i-BN3Q1g&si=DcihOwUkd9oWbbdp https://youtube.com/playlist?list=PLidqqIGKox7WeOKVGHxcd69kKqtwrKl8W&si=Y8MsO-FK948jnxpS https://youtube.com/playlist?list=PLidqqIGKox7UVC-8WC9djoeBzwxPeXph7&si=-7i5Iq7yOeJrhtu6 https://youtube.com/playlist?list=PLidqqIGKox7VKJD2WxRhoKaI6JGLVean8&si=NH_Q1ujhVgACM2FU #Alevel #Biology #study #revision #school #exam #AQA #OCR #Edexcel