129 articles
Biochemistry & the Chemistry of Life
Proteins, carbohydrates, lipids, DNA, enzymes and the chemistry happening inside living things.
Endorphins: The Body's Natural Painkillers
What endorphins are: peptides that act on the same receptors as morphine, how they were discovered, how they're made and work, when the body releases them, the truth about the 'runner's high', and how opioid drugs and naloxone relate to them.
Investigating Enzyme Activity: Catalase and Amylase
Two school-lab-safe enzyme practicals with full methods: measuring catalase activity from oxygen gas volume, and timing amylase digestion of starch with iodine, including variables, results tables, rate calculations and sources of error.
Enzymes: How They Work
A beginner's guide to enzymes: what biological catalysts are, how active sites and substrates fit, how enzymes lower activation energy, specificity, naming, the factors that affect activity, and enzymes at work in the body and industry.
Essential Amino Acids and Where to Find Them
The nine essential amino acids listed one by one, with what each does and good food sources, plus conditionally essential amino acids, complete vs incomplete proteins, protein combining and how much protein adults need.
How Temperature and pH Affect Enzymes
Why enzyme activity rises then crashes with temperature, why each enzyme has an optimum pH, how substrate and enzyme concentration change the rate, and what the classic graphs mean, explained with collision theory and denaturation.
Lipids: Fats, Oils, Phospholipids and Steroids
What lipids are and why they don't dissolve in water: triglycerides, fats vs oils, phospholipids and membranes, steroids, waxes, how the body digests and stores fat, energy content and the emulsion test.
Dietary Minerals: Why Your Body Needs Metals
A list of the essential dietary minerals, grouped into major minerals and trace elements, with what each does chemically, good food sources and what happens when you get too little or too much, from calcium and sodium to iron, zinc, iodine and selenium.
Penicillin: Discovery and Chemistry
The story of penicillin from Alexander Fleming's contaminated plate in 1928 to Florey, Chain and Heatley's rescue of the idea, wartime mass production from a mouldy melon, Dorothy Hodgkin's structure of the β-lactam ring, and the chemistry that makes it work.
Photosynthesis vs Respiration
Photosynthesis and respiration compared side by side: equations, energy, where and when they happen, redox, ATP, the organelles and electron transport chains involved, compensation points, and how the two processes cycle carbon and oxygen.
Proteins: Chains of Amino Acids
A beginner's guide to proteins: how amino acids link into chains, how chains fold into shapes, the many jobs proteins do, why shape decides function, what denaturation is, protein in the diet and how proteins are made.
Benedict's Test for Reducing Sugars
A school-lab guide to Benedict's test: the redox chemistry behind the colour change, a safe step-by-step method, semi-quantitative colour scale, testing sucrose by acid hydrolysis, results tables and sources of error.
The Iodine Test for Starch
A school-lab guide to the iodine test for starch: why iodine turns blue-black inside the amylose helix, a safe method for foods and solutions, testing leaves for photosynthesis and following starch digestion by amylase, with sources of error.
What Is Biochemistry?
Biochemistry is the chemistry of living things. Learn what biochemists study, the elements and molecules life is built from, the key ideas that link chemistry to biology, and where biochemistry is used, from medicine to food.
What Elements Are in the Human Body?
The six elements that make up about 99% of your body mass, the essential minerals and trace elements, what each one does, and why you're mostly oxygen by mass but mostly hydrogen by atoms.
ATP vs ADP
ATP vs ADP compared: structure, phosphoanhydride bonds, why hydrolysis releases energy, the ATP–ADP cycle, how ATP is regenerated, AMP as a signal and common misconceptions.
Blood Sugar Regulation: A Chemical Feedback Loop
How the body holds blood glucose near 5 mmol/L: negative feedback, insulin and glucagon, the liver as a glucose buffer, cell signalling, amplification, and what goes wrong in diabetes.
Enzyme Misconceptions
Nine common misconceptions about enzymes — that they're alive, get used up, only work at 37 °C, or change the equilibrium — each corrected with the real chemistry.
Fermentation Biochemistry: Alcoholic and Lactic
The biochemistry of fermentation: why cells ferment, NAD⁺ recycling, the alcoholic pathway in yeast and the lactic pathway in muscle and bacteria, yields, and uses in food.
Fibrous vs Globular Proteins
Fibrous vs globular proteins compared: shape, sequence, solubility, bonding, stability and function, with collagen, keratin, haemoglobin and enzymes as worked examples.
Starch vs Cellulose
Starch vs cellulose compared: α- vs β-glucose, helix vs straight chains, hydrogen bonding, solubility, digestion, iodine test and uses — why one tiny difference changes everything.
Measuring Vitamin C in Fruit Juice
A lab guide to measuring vitamin C in juice by iodine titration with a starch indicator: the redox chemistry, standardisation, method, full calculation and sources of error.
How the Body Metabolises Alcohol
The chemistry of ethanol in the body: absorption, oxidation to ethanal and ethanoic acid, zero-order elimination, the flushing reaction, hangovers, methanol and breathalysers.
Antioxidants: What They Really Do
What an antioxidant is chemically, how vitamins C and E and glutathione stop radical chains, antioxidants in food preservation, and why supplements disappoint.
Biochemistry Practice Questions
15 exam-style biochemistry questions on biomolecules, enzymes, respiration, photosynthesis and DNA, with a full answer key and worked calculations.
Biochemistry Study Guide
A syllabus-style biochemistry checklist for high school and first-year students: biomolecules, enzymes, respiration, photosynthesis, DNA, key facts and exam tips.
Bioluminescence: How Fireflies Glow
The chemistry of living light: luciferin, luciferase, ATP and oxygen in fireflies, why the light is cold, jellyfish GFP, glowing oceans, and uses in the lab.
Blood Chemistry: What a Blood Test Measures
A chemistry student's guide to a blood test: what's in plasma, units like mmol/L, electrolytes, glucose, kidney and liver markers, lipids, and the chemistry behind the measurements.
The Chemistry of Ageing: Free Radicals and Oxidative Stress
What free radicals are, how mitochondria produce reactive oxygen species, how they damage lipids, proteins and DNA, the body's defences, and other chemical theories of ageing.
Histamine and the Chemistry of Allergies
What happens chemically in an allergy: IgE, mast cells, histamine and its receptors, why antihistamines work, anaphylaxis and adrenaline, and common allergens explained.
The Immune System as Chemistry: Antibodies and Antigens
The immune system explained through molecules: antigens and epitopes, antibody structure, binding forces, complement, the oxidative burst, and how lateral flow tests use antibodies.