Study Notes
Biological molecules in living organisms are mainly carbohydrates, proteins, and lipids, all of which contain carbon and are organic. Carbohydrates are long chains of simple sugars like glucose. Example: Starch is a polysaccharide formed from glucose molecules. Lipids are made of triglycerides, consisting of glycerol and fatty acids. Example: Fats are solid lipids at room temperature. Proteins are long chains of amino acids with unique sequences and shapes. Example: Enzymes are proteins with specific active sites for reactions. DNA is a double helix molecule containing genetic instructions. Example: Adenine pairs with Thymine in DNA. Enzymes are proteins that act as biological catalysts. Example: Amylase breaks down starch.
Exam Tips
Key Definitions to Remember
- Carbohydrates are organic molecules made of simple sugars.
- Lipids are organic molecules made of glycerol and fatty acids.
- Proteins are organic molecules made of amino acids.
- DNA is a molecule containing genetic instructions in a double helix.
- Enzymes are proteins that speed up chemical reactions.
Common Confusions
- Confusing the terms 'denatured' and 'dying' for enzymes.
- Mixing up the roles of different enzymes like protease and lipase.
Typical Exam Questions
- What is the basic unit of carbohydrates? Simple sugars like glucose.
- How do enzymes function? They speed up reactions without being used up.
- What is the structure of DNA? A double helix with base pairs.
What Examiners Usually Test
- Understanding of food tests and their color changes.
- The role of sugars, amino acids, and fatty acids in biological molecules.
- The effect of temperature and pH on enzyme activity.