Biology - Cell Structure and Functions Notes
1. What is a Cell?
The cell is the basic structural, functional, and biological unit of all living organisms. Cells can be prokaryotic
(without nucleus) or eukaryotic (with nucleus).
2. Discovery of Cell
- Discovered by Robert Hooke in 1665
- Cell Theory was proposed by Schleiden and Schwann
- All living organisms are made up of cells
3. Types of Cells
- Prokaryotic Cells: Lack a true nucleus (e.g., bacteria)
- Eukaryotic Cells: Have a well-defined nucleus (e.g., plant and animal cells)
4. Cell Organelles and Functions
- Nucleus: Controls cell activities, contains genetic material
- Mitochondria: Powerhouse of the cell, produces energy
- Endoplasmic Reticulum: Synthesizes proteins and lipids
- Golgi Apparatus: Modifies, sorts, and packages proteins
- Lysosomes: Digestive system of the cell
- Ribosomes: Site of protein synthesis
5. Plant Cell vs Animal Cell
- Plant cells have a cell wall and chloroplasts, animal cells do not
- Plant cells have a large central vacuole; animal cells have smaller ones
6. Importance of Cells
- Carry out essential life processes
- Help in growth, repair, reproduction
- Specialized cells perform different functions in multicellular organisms
1. What is a Cell?
The cell is the basic structural, functional, and biological unit of all living organisms. Cells can be prokaryotic
(without nucleus) or eukaryotic (with nucleus).
2. Discovery of Cell
- Discovered by Robert Hooke in 1665
- Cell Theory was proposed by Schleiden and Schwann
- All living organisms are made up of cells
3. Types of Cells
- Prokaryotic Cells: Lack a true nucleus (e.g., bacteria)
- Eukaryotic Cells: Have a well-defined nucleus (e.g., plant and animal cells)
4. Cell Organelles and Functions
- Nucleus: Controls cell activities, contains genetic material
- Mitochondria: Powerhouse of the cell, produces energy
- Endoplasmic Reticulum: Synthesizes proteins and lipids
- Golgi Apparatus: Modifies, sorts, and packages proteins
- Lysosomes: Digestive system of the cell
- Ribosomes: Site of protein synthesis
5. Plant Cell vs Animal Cell
- Plant cells have a cell wall and chloroplasts, animal cells do not
- Plant cells have a large central vacuole; animal cells have smaller ones
6. Importance of Cells
- Carry out essential life processes
- Help in growth, repair, reproduction
- Specialized cells perform different functions in multicellular organisms
