Enzymes and Characteristics of Living Organisms

Enzymes

• Enzymes are biological catalysts, typically proteins, that accelerate chemical reactions in living organisms.
• They function by lowering the activation energy needed for a reaction to occur.
• Enzymes are highly specific, meaning they typically catalyze only one type of reaction.
• Enzyme activity is affected by factors such as temperature and pH.
• Enzymes have an active site, a specific region where the substrate binds.
• The substrate binds to the active site resulting in an enzyme-substrate complex.
• The reaction occurs, and the product is released from the enzyme.
• Enzymes can be regulated to control the rate of the reactions they catalyze.
• Enzyme inhibition happens when a molecule binds to the enzyme and reduces its activity.

Characteristics and Classification of Living Organisms

• Living organisms share several key characteristics:
  • Organization: Composed of cells.
  • Metabolism: Carry out chemical reactions to obtain energy and build materials.
  • Growth: Increasing in size and complexity.
  • Adaptation: Adjusting to the environment.
  • Response: Reacting to stimuli.
  • Reproduction: Producing offspring.
  • Homeostasis: Maintaining a stable internal environment.
• Living organisms can be classified into various groups such as:
  • Bacteria: Prokaryotic, unicellular organisms.
  • Archaea: Prokaryotic, often found in extreme environments.
  • Protists: Eukaryotic, unicellular organisms or simple multicellular organisms.
  • Fungi: Eukaryotic, obtain nutrients through absorption.
  • Plants: Eukaryotic, multicellular organisms that primarily perform photosynthesis.
  • Animals: Eukaryotic, multicellular organisms that obtain nutrients by ingestion.

Cell Structure and Organisation

• Cells are the basic units of life.
• There are two main types of cells: prokaryotic and eukaryotic.
• Prokaryotic cells lack a nucleus and membrane-bound organelles.
• Eukaryotic cells have a nucleus and membrane-bound organelles, such as mitochondria and the endoplasmic reticulum.
• Cellular organization typically involves specialized cells working together in tissues, tissues forming organs, and organs forming organ systems.

Diffusion and Osmosis

• Diffusion is the net movement of molecules from a region of high concentration to a region of low concentration.
• The driving force behind diffusion is the concentration gradient.
• Diffusion continues until equilibrium is reached, where there is an equal concentration of molecules throughout a space.
• Diffusion occurs in liquids and gases.
• Osmosis is the movement of water across a semi-permeable membrane from a region of high water concentration to a region of low water concentration.
• Osmosis is a type of diffusion that specifically involves water molecules.
• The concentration of solutes affects water movement in osmosis, as water moves to equalize the concentration of solutes on both sides of the membrane.
• Osmosis is crucial for maintaining the water balance within cells and organisms.
• Different environments affect cells differently depending on the relative concentration of solutes inside and outside the cell (hypotonic, isotonic, hypertonic).

Explore the fascinating world of enzymes, the biological catalysts that speed up chemical reactions in living organisms. This quiz also covers the essential characteristics that define life, such as organization and metabolism. Test your knowledge on how enzymes work and their crucial role in biological processes.