A-Level Biology - Blood Vessels - Artery | Arteriole | Capillary | Venule | Vein (2026/27 exams)

⭐️ Check out our website https://www.cognito.org/ ⭐️ *** WHAT'S COVERED *** 1. The five main types of blood vessels and the general path of blood circulation. * Arteries, arterioles, capillaries, venules, and veins. * Blood flow from the heart, around the body, and back to the heart. 2. The detailed structure and adaptations of arteries. * Handling high pressure with thick, strong, and flexible walls. * The roles of collagen, elastic fibres, and smooth muscle. * Vasoconstriction and vasodilation to control blood flow. 3. The structure and function of arterioles. * Connection between arteries and capillaries. * Role in controlling blood flow into capillary networks. 4. The specialised structure and adaptations of capillaries. * Function as the site for substance exchange between blood and tissues. * Adaptations including extremely thin walls (one cell thick) and a very narrow lumen. 5. The structure and adaptations of veins and venules. * Handling low-pressure blood flow back to the heart. * Features like a large lumen, thinner walls, and the presence of valves. * How valves and skeletal muscles work together to prevent the backflow of blood. *** CHAPTERS *** 0:00 Introduction to Blood Vessels 0:21 The Five Types of Blood Vessels 1:07 General Structure of Blood Vessels 1:34 Arteries: Structure and Adaptations 2:16 Vasoconstriction and Vasodilation 2:51 Elastic vs Muscular Arteries 3:16 Arterioles: Structure and Adaptations 3:47 Capillaries: Structure and Adaptations 5:20 Veins: Structure and Adaptations 5:54 How Valves in Veins Prevent Backflow 6:58 Venules: Structure and Adaptations *** PLAYLISTS *** https://youtube.com/playlist?list=PLidqqIGKox7VzYfPIVt8T09xOLNcolCe4&si=8JmDajxjtba6rdc3 https://youtube.com/playlist?list=PLidqqIGKox7UZ3mWhbHv2aA_1vnbsfRPq&si=q3hEKdA4v7kbfwMe https://www.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