C1.1.1— Enzymes as catalysts.

• Define catalyst.
• State the role of enzymes in the chemical reactions on which life is based.
• State that enzymes speed up chemical reactions without being altered, so can be reused.

Define Catalyst:

A Catalyst is a substance that can lower ⬇️ the activation energy 🔆 in a reaction while leaving the reaction unchanged, 🙅‍♀️ thus causing an increase ⬆️ in the rate of reaction. 🧪

State the role of enzymes in the chemical reactions on which life is based:

• 🍕⬇️→ 👶 & 💪
• Enzymes play central roles in chemical reactions on which life are based:
• They’re central to metabolism, digestion and the breakdown of complex molecules for energy (catabolism) and the synthesis of complex molecules for the growth and repair of the body (anabolism)

Two Types of Reactions:

Catabolic Reactions:

• Complex molecules (Proteins, Carbs, Lipids, etc) into simpler ones (Amino Acids, Sugars, Fatty Acids)
• Releases energy by breaking chemical bonds, what’s released is usually ATP
• Pro tip: Remember, Cats like breaking stuff and destroying it, they also rip stuff apart for their food 🐈

IMPORTANT CATABOLIC REACTIONS

• Glycolysis: The breakdown of glucose into pyruvate (3carbonacid naturally formed during glycolysis) in the cytoplasm.
• Cellular Respiration: The oxidation of glucose and other organic molecules to produce ATP.
• Protein Degradation: The breakdown of proteins into amino acids.
• Lipolysis: The breakdown of fats into fatty acids and glycerol.