Lecture Notes: Introduction to Cells and Organelles

Opening Thoughts

• Importance of engaging science experiences.
  • Example: Observing an amoeba under a microscope sparked a love for science.
• Fascination with cells:
  • Single-celled organisms like amoebas.
  • Multicellular organisms like humans.

Modern Cell Theory

• First Statement: Cell is the smallest living unit in organisms.
• Second Statement: All living things are composed of one or more cells.
• Third Statement: All cells arise from pre-existing cells.

Types of Cells

• Prokaryotes
  • No nucleus or membrane-bound organelles.
  • Examples: Bacteria and Archaea.
• Eukaryotes
  • Have a nucleus and membrane-bound organelles.
  • Examples: Plants, animals, fungi, and protists.

Commonalities Between Prokaryotes and Eukaryotes

• Genetic material.
• Cytoplasm.
• Ribosomes for protein synthesis.
• Cell membranes for selective permeability.

Organelles and Their Functions

Plasma Membrane

• Selectively permeable to maintain homeostasis.

Cytoplasm

• Jelly-like material that supports organelles.

Ribosomes

• Not membrane-bound.
• Protein synthesis.
• Present in both prokaryotes and eukaryotes.

Eukaryotic Organelles

• Nucleus
  • Contains genetic material (DNA).
  • Controls cell activities.
  • Contains nucleolus for ribosome production.
• Endoplasmic Reticulum (ER)
  • Rough ER: Protein production and transport.
  • Smooth ER: Lipid production, detoxification.
  • Transports molecules via vesicles.
• Golgi Apparatus
  • Packaging and modifying center.
  • Sorts and directs molecules.

Mitochondria

• Produces ATP energy via cellular respiration.

Plant vs. Animal Cells

• Plant Cells
  • Contain chloroplasts for photosynthesis.
  • Have a large central vacuole.
  • Possess a cell wall for additional protection.
• Animal Cells
  • May have multiple smaller vacuoles.

Conclusion

• Cell organelles each have distinct functions.
• Encouragement to explore more about cell biology.

Stay curious and continue to explore the world of cells!