BIO101 ‒ Topic 2: The Cell (Structure and Function)
1. Definition and Discovery of the Cell
Cells are the basic structural, functional, and biological units of all living organisms. They
are often referred to as the 'building blocks of life.' The discovery of the cell is credited to
Robert Hooke in 1665, who observed cork cells using a primitive microscope.
2. Types of Cells (Prokaryotic and Eukaryotic)
Prokaryotic cells lack a true nucleus and membrane-bound organelles (examples: bacteria
and archaea). Eukaryotic cells possess a true nucleus and various organelles (examples:
plant, animal, and fungal cells).
3. Structure and Functions of Cell Organelles
Major organelles include the nucleus (controls activities), mitochondria (energy
production), ribosomes (protein synthesis), endoplasmic reticulum (transport and
synthesis), Golgi apparatus (modification and packaging), lysosomes (digestion), and
vacuoles (storage).
4. Differences Between Plant and Animal Cells
Plant cells contain chloroplasts, a cell wall, and a large central vacuole; animal cells lack
these but contain centrioles and smaller vacuoles.
5. Cell Membrane Structure and Transport Mechanisms
The cell membrane consists of a phospholipid bilayer with embedded proteins. It regulates
movement of substances in and out of the cell via diffusion, osmosis, and active transport.
6. Cell Specialization
In multicellular organisms, cells are specialized to perform particular functions ̶ for
example, nerve cells transmit impulses, and red blood cells transport oxygen.
7. Revision Questions and Answers
Q1: Who discovered the cell?
A: Robert Hooke in 1665.
Q2: State two differences between prokaryotic and eukaryotic cells.
A: Prokaryotic cells lack a nucleus and membrane-bound organelles; eukaryotic cells
1. Definition and Discovery of the Cell
Cells are the basic structural, functional, and biological units of all living organisms. They
are often referred to as the 'building blocks of life.' The discovery of the cell is credited to
Robert Hooke in 1665, who observed cork cells using a primitive microscope.
2. Types of Cells (Prokaryotic and Eukaryotic)
Prokaryotic cells lack a true nucleus and membrane-bound organelles (examples: bacteria
and archaea). Eukaryotic cells possess a true nucleus and various organelles (examples:
plant, animal, and fungal cells).
3. Structure and Functions of Cell Organelles
Major organelles include the nucleus (controls activities), mitochondria (energy
production), ribosomes (protein synthesis), endoplasmic reticulum (transport and
synthesis), Golgi apparatus (modification and packaging), lysosomes (digestion), and
vacuoles (storage).
4. Differences Between Plant and Animal Cells
Plant cells contain chloroplasts, a cell wall, and a large central vacuole; animal cells lack
these but contain centrioles and smaller vacuoles.
5. Cell Membrane Structure and Transport Mechanisms
The cell membrane consists of a phospholipid bilayer with embedded proteins. It regulates
movement of substances in and out of the cell via diffusion, osmosis, and active transport.
6. Cell Specialization
In multicellular organisms, cells are specialized to perform particular functions ̶ for
example, nerve cells transmit impulses, and red blood cells transport oxygen.
7. Revision Questions and Answers
Q1: Who discovered the cell?
A: Robert Hooke in 1665.
Q2: State two differences between prokaryotic and eukaryotic cells.
A: Prokaryotic cells lack a nucleus and membrane-bound organelles; eukaryotic cells
