I. Adaptation of chloroplast and mitochondria to their functions:

I. Adaptation of chloroplast and mitochondria to their functions:

• Chloroplast:

  • Thylakoids are stacked into grana, increasing the surface area for light-dependent reactions and maximizing light absorption by chlorophyll.
  • The stroma contains enzymes necessary for the light-independent reactions (Calvin cycle) to synthesize sugars.

• Mitochondria:

  • The inner membrane is highly folded into cristae, which greatly increases the surface area for the electron transport chain and ATP synthase, maximizing ATP production during cellular respiration.
  • The matrix contains enzymes for the Krebs cycle and link reaction, as well as mitochondrial DNA and ribosomes, facilitating energy production.

II. Differentiation between a bacterial and a chlorenchyma cell using electron microscope structures:

• A chlorenchyma cell (plant cell) possesses a true nucleus enclosed by a nuclear envelope, chloroplasts for photosynthesis, and mitochondria for respiration. It also has a large central vacuole and a cell wall made of cellulose.
• A bacterial cell (prokaryote) lacks a true nucleus (having a nucleoid region instead), lacks membrane-bound organelles like chloroplasts and mitochondria, and has a cell wall made of peptidoglycan.

III. Advantages and disadvantages of using light and electron microscopes to study cell organelles:

• Light Microscope (LM):

  • Advantages: Can view living specimens, relatively inexpensive, and has simple sample preparation.
  • Disadvantages: Lower resolution and magnification, limiting the detail of internal organelles.

• Electron Microscope (EM):

  • Advantages: Offers much higher resolution and magnification, revealing fine details of internal cell structures and organelles.
  • Disadvantages: Cannot view living specimens (samples must be in a vacuum), is expensive to purchase and maintain, and requires complex sample preparation.