Cells are the basic unit of all living organisms, containing organelles and bounded by a plasma membrane. The cell theory, developed by Schleiden and Schwann in the 1800s, states that all living things are composed of cells, cells are the fundamental unit of life, and new cells are produced from existing cells. Key cellular components include the plasma membrane, cytoplasm, genetic material (DNA or RNA), and ribosomes. Cells carry out functions like metabolism, communication, and inheritance of DNA.

1.  What is a cell?
 Cell theory
 Basic stuctions of the cell
 Functions of the cell
 Types of cell

2.  Cells are the basic unit
of living organisms.
 Smallest unit that can
carry out functions of
living organisms.
 Contain Organelles
“ Small organs”

3.  Robert Hooke (1500’s) was first to use the term “cell”
 Schleiden (botanist) and Schwann (zoologist) (1800’s) make individual
observations about cells and form the cell theory.
Its postulates state that:
1. All living things are composed of cells
2. The cell is the simplest structural unit of all living things.
3. All cells come from other cells

4. Basic Structure of the Cell
 Plasma membrane-the outermost envelope
 Cytosol - fluid component within the cell
 Organelles - structures that carry out functions
 Nucleus
Functions of the Cell
 Communication. Cells produce and receive electrical
and chemical signals
 Cell metabolism and energy release
 Inheritance. Each cell contains DNA. Some cells are
specialized as gametes for exchange during sexual
intercourse

6. What do ALL cells have in common?
 Cell membrane (aka plasma membrane)
 Cytoplasm
 Genetic material (DNA or RNA)
 Ribosomes (produce proteins)
 Metabolism

7.  Cell membrane
A selectively permeable
phospholipid bilayer that
forms a barrier between
the cell and its environment
 Cytoplasm
Liquid substance that all
chemical reactions of life take
place in Has dissolved ions,
macromolecules Fills in around
the organelles of the cell

8.  Genetic Material DNA is
found as either: organized
chromosomes (eukaryotes)
Inside Nucleus single, loosely
packed chromosome (prokaryotes)
Ribosomes
Two-piece protein-based organelle
that makes proteins in both major
types of cell Varies structurally in
prokaryotes and eukaryotes