GCSE Biology: Organisation — Deep Revision Workbook

Inside GCSE Biology: Organisation — Deep Revision Workbook

build cells into tissues, organs and systems and follow food through the gut, master enzymes and the food tests, revise heart chambers, vessels and blood cells, then tackle coronary heart disease, risk factors, cancer and plant transport, before finishing with an extended exam-style application. About 45 minutes.

Learning objectives

• organisation and the digestive system — cells, tissues, organs and organ systems, the gut tissues, and where food is churned, absorbed and water reclaimed;
• enzymes and food tests — biological catalysts, the active site, denaturing, lipase products, the iodine, Benedict’s and Biuret tests, and reaction rate;
• the heart, blood vessels and blood — the chambers, the pulmonary vein, the pacemaker, and red cells, white cells, platelets and plasma;
• health, disease and plant transport — coronary heart disease, risk factors, non-communicable disease, benign and malignant tumours, and the transpiration stream;
• extended exam application — a 6-mark answer on the blood, and applying heart-disease knowledge to lifestyle risk.

Activities in this book

1. Section 1 — Organisation & the Digestive System

   living things are organised from cells into tissues, organs and organ systems. In the gut, muscular, glandular and epithelial tissues build organs like the stomach; food is churned in the stomach, digested and absorbed in the small intestine, and water is absorbed in the large intestine. Bile, made in the liver, is stored in the gall bladder.

2. Section 2 — Enzymes & Food Tests

   enzymes are biological catalysts. A substrate fits the active site by the lock-and-key model; heat or the wrong pH changes the active site shape so the enzyme denatures. Lipase breaks lipids into glycerol and fatty acids. Learn each food test as a reagent-plus-colour pair: iodine (starch), Benedict’s (reducing sugar) and Biuret (protein).

3. Section 3 — The Heart, Blood Vessels & Blood

   the heart is a double pump: the left ventricle has the thickest wall to pump oxygenated blood around the whole body. Veins carry blood back to the heart and have valves; the pulmonary vein carries oxygenated blood from the lungs to the heart. Blood is red blood cells (haemoglobin, oxygen), white blood cells (defence), platelets (clotting) and plasma (transport).

4. Section 4 — Health, Disease & Plant Transport

   in coronary heart disease, fatty deposits narrow the coronary arteries. Non-communicable diseases such as cancer cannot be passed between people; smoking, poor diet and inactivity are risk factors. A benign tumour stays in one place; a malignant one spreads. In plants, water travels up the xylem in the transpiration stream, faster in hot, dry, windy conditions.

5. Section 5 — Extended Exam-Style Application

   exam questions reward joined-up biology: link a structure to its function, and back up each claim with a reason. For a 6-mark question, plan four or five clear points, use the correct key terms, and answer every part of the question.

Suggestions for teaching

• Build the hierarchy first. Make sure learners can order cells → tissues → organs → organ systems and name the gut tissues before moving on.
• Drill the food tests as pairs. Link each reagent to its colour change (iodine → blue-black, Benedict’s → brick red, Biuret → purple).
• Use the lock-and-key model. Explain that heat or the wrong pH changes the active site shape so the enzyme denatures and the substrate no longer fits.
• Contrast the vessels and chambers. Compare artery, vein and capillary structure, and why the left ventricle has the thickest wall.
• Follow water and sugar. Separate the xylem (water, transpiration) from the phloem (sugars, translocation), and cover the factors that speed transpiration.