Engaging in Science: Reflect on the most exciting science class experiences such as worm dissection, owl pellet analysis, osmosis eggs, genetic experiments with fruit flies.
Personal Anecdote: Discovery of an amoeba in 9th grade science class sparked interest in science.
The Cell Theory
Smallest Living Unit: The cell is the smallest living unit in all organisms.
Composition: All living things are made of cells (unicellular like amoebas or multicellular like humans).
Cell Reproduction: All cells come from pre-existing cells.
Cell Types
Prokaryotes vs. Eukaryotes
Common Features: Both have genetic material, cytoplasm, ribosomes, and cell membranes.
Differences:
Prokaryotes: No nucleus, no membrane-bound organelles.
Eukaryotes: Have nucleus and membrane-bound organelles.
Exploring the Cell
Cell Membrane: Selectively permeable to maintain homeostasis.
Cytoplasm: Jelly-like material surrounding organelles.
Cytoskeleton: Provides support and can aid in movement.
Key Organelles in Eukaryotes
Ribosomes
Not membrane-bound.
Make proteins; found in both prokaryotes and eukaryotes.
Nucleus
Holds genetic material (DNA).
Controls cell activities.
Contains nucleolus (ribosome production).
Endoplasmic Reticulum (ER)
Rough ER: Has ribosomes, involved in protein production and transport.
Smooth ER: Involved in detoxification and lipid production.
Golgi Apparatus
Packaging center for molecules.
Modifies, sorts, and directs molecules for secretion or internal use.
Mitochondria
Powerhouse of the cell, produces ATP through cellular respiration.
Distinctions Between Plant and Animal Cells
Chloroplasts (in plants): Conduct photosynthesis by converting light energy to glucose.
Vacuoles
Plant cells: Large central vacuole.
Animal cells: Several smaller vacuoles.
Cell Wall (in plants): Provides additional protection and structure.
Conclusion
Summary: Recap of cell components and their functions.
Encouragement: Stay curious and explore more about organelles in eukaryotic cells.