Introduction to Cell Biology
LEARNING OBJECTIVES
1. Explain what cells are.
2. Outline the history of cell discovery and the importance of microscopy.
3. Describe how cells differ in size, structure, and function.
What are cells?
Cells are small units filled with a concentrated aqueous solution of chemicals (aka CYTOSOL), bound
by a plasma membrane (or cell wall e.g. plants).
Remember key vocab.
• Greek for “hollow vessel”
• Prefix → “cyto…”
• Suffix → “…cyte”
• Cytology → microscopic study of cell structure and organisation
• Cytochemistry → Cell chemistry
• Immuno → immune system, relating to antibodies
• Endocytosis → moving INTO cells
• Exocytosis → Moving OUT OF cells
• EXAMPLES → Hepatocyte = liver cell
Cells are FUNDAMENTAL UNITS OF LIFE
They are the smallest functional component of a multicellular organism: THE SMALLEST LIVING
ENTITY.
Some organisms are unicellular e.g. bacteria and Amoeba
• Cells are not always small though e.g. Frog cells are 1mm in diameter
• Simplest form of life = SOLITARY cells
Animals and plants are a vast colony of cells. Their function is regulated by intricate systems of cell-
to-cell communication.
Contents of a cell
• Cytosol = aqueous fluid
• Cytoplasm = Chemicals
• Cytoskeleton = structural support
• Membrane bound organelles IN EUKARYOTES ONLY
, Relative sizes/dimensions
Organism - BIGGEST
Organ Systems
• Includes the 11 body systems e.g. endocrine, reproductive,
cardiovascular etc (discussed in Lectures 1 and 2 in Sem B)
Organs
• Solid structures
Tissue
• Collection of cells; can be liquid e.g. blood
Cell
Organelle
• E.g. mitochondrion (involved in oxidative phosphorylation)
Molecule
• Carbs, fats, proteins, RNA/DNA
Atom - SMALLEST
• Hydrogen, Carbon, Nitrogen, Oxygen
LEARNING OBJECTIVES
1. Explain what cells are.
2. Outline the history of cell discovery and the importance of microscopy.
3. Describe how cells differ in size, structure, and function.
What are cells?
Cells are small units filled with a concentrated aqueous solution of chemicals (aka CYTOSOL), bound
by a plasma membrane (or cell wall e.g. plants).
Remember key vocab.
• Greek for “hollow vessel”
• Prefix → “cyto…”
• Suffix → “…cyte”
• Cytology → microscopic study of cell structure and organisation
• Cytochemistry → Cell chemistry
• Immuno → immune system, relating to antibodies
• Endocytosis → moving INTO cells
• Exocytosis → Moving OUT OF cells
• EXAMPLES → Hepatocyte = liver cell
Cells are FUNDAMENTAL UNITS OF LIFE
They are the smallest functional component of a multicellular organism: THE SMALLEST LIVING
ENTITY.
Some organisms are unicellular e.g. bacteria and Amoeba
• Cells are not always small though e.g. Frog cells are 1mm in diameter
• Simplest form of life = SOLITARY cells
Animals and plants are a vast colony of cells. Their function is regulated by intricate systems of cell-
to-cell communication.
Contents of a cell
• Cytosol = aqueous fluid
• Cytoplasm = Chemicals
• Cytoskeleton = structural support
• Membrane bound organelles IN EUKARYOTES ONLY
, Relative sizes/dimensions
Organism - BIGGEST
Organ Systems
• Includes the 11 body systems e.g. endocrine, reproductive,
cardiovascular etc (discussed in Lectures 1 and 2 in Sem B)
Organs
• Solid structures
Tissue
• Collection of cells; can be liquid e.g. blood
Cell
Organelle
• E.g. mitochondrion (involved in oxidative phosphorylation)
Molecule
• Carbs, fats, proteins, RNA/DNA
Atom - SMALLEST
• Hydrogen, Carbon, Nitrogen, Oxygen
