Acids:
1. Citric Acid (Plants): Found in citrus fruits like lemons, oranges, and grapefruits. It gives them their sour taste and acts as a natural preservative.
2. Lactic Acid (Animals): Produced in muscle cells during intense physical activity. It contributes to muscle fatigue and soreness.
Bases:
3. Alkaloids (Plants): A diverse group of organic compounds found in many plants, often with medicinal properties. Examples include caffeine (coffee, tea), nicotine (tobacco), and morphine (opium poppy). These can be quite alkaline.
4. Ammonia (Animals): A byproduct of protein metabolism in animals, particularly in mammals. It's a waste product and is excreted in urine. Ammonia is basic in solution.
5. Bicarbonate (Animals): Found in blood and other bodily fluids, acting as a buffer to help maintain a stable pH. Bicarbonate is a base.
Note: There are many other acidic and basic substances found in plants and animals. This is just a small sample to give you an idea of the diversity.
