Introduction to Cells

1
Introduction to Cells
2
The Cell Theory

• All living things are composed of cells.
• Cells are the basic units of structure and
  function in living things.
• New cells are produced from existing cells.

3
Levels of Organization

• Put these terms in order from smallest to
  largest

Organism
Molecule
Cell
Organ
Organ System
Tissue
4
Give an example of each level

• Molecule
• Cell
• Tissue
• Organ
• Organ System
• Organism

5
What do you notice?
6
Types of Cells

• Two kinds of cells depending on whether they have
  a nucleus

Eukaryote
Prokaryote
Genetic material
7
Prokaryotes

• Usually small and simple
• Genetic material (DNA) is not contained in a
  nucleus
• The ONLY prokaryotes in the world are BACTERIA.

8
Prokaryotic Cells
9
Eukaryotes

• Larger and more complex than prokaryotes.
• May be unicellular like an amoeba or
  multicellular like a plant
• Contain dozens of specialized structures called
  organelles.
• Examples protists, fungi, plants and animals.

10
Eukaryotic cells
11
Eukaryotic cell structure

• Two major parts
• Nucleus
• Cytoplasm-portion of the cell outside the nucleus