1. Determining the Basis of Life
Unit 2
Chapter 6
Lesson 2

2. Lesson Introduction
What is the difference between prokaryotic and eukaryotic cells?
Why is a virus structure not truly a cell?
Differentiate between a cell membrane and a cell wall.
Why is cell specialization important to human, animal, and plant life?

3. Structural Basis of Life
What are cells?
Structural unit that makes up all living things
Many variations that all appear similar but have different cell structure
General pattern of organization and relationship in a cell

4. Bacteria cell Plasma Membrane Cytoplasm Cell wall DNA Ribosomes Pili
Flagella

5. Virus Structure
Head
DNA
Tail sheath
Tail fiber

6. Prokaryotic Cell (Single Celled Organisms)
Cell Membrane
Ribosomes
DNA
Cell Wall

7. Eukaryotic Cell (Animal)
Vacuole
Nucleus
Cell Membrane
Lysosome
Nuclear Membrane
Ribosome
Smooth ER*
Rough ER*
Chromatin
Mitochondria
Golgi Body
Nucleolus
*ER = Endoplasmic Reticulum
Cytoplasm

8. Eukaryotic Cell (Plant)
Chloroplast
Cell Wall
Nucleus
Golgi Body
Nuclear Membrane
Ribosome
Smooth ER*
Rough ER*
Chromatin
Mitochondria
Vacuole
Nucleolus
*ER = Endoplasmic Reticulum
Cytoplasm

9. Cell Membranes What is a cell membrane?
Surrounds the animal cells
Gives shape and flexibility to cell
Controls movement of material in and out of the cell – very selective
Plants have a cell wall that provides structure to the plant and protects the cell
Animals don’t need structure from cell walls- they have skeletons to provide structure
Video Clip

10. Nucleus Near the center of the cell Surrounded by the nuclear membrane
Gives shape and flexibility to nucleus
Controls movement of material in and out of the nucleus – very selective
Command center for the cell
Stores genetic information on chromatin
Structure found in the nucleus that carries genetic information on DNA
Holds the nucleolus
Synthesizes ribosomes
Holds the cells RNA
Video Clip

11. Cell Parts Cytoplasm Microfilament Microtubules
Thick, semi-fluid (like hair gel) material that surrounds the nucleus.
Holds organelles in place
Provides protection to the nucleus
Helps to rid the cell of waste.
Microfilament
Help shape and support the cell
Provide movement
Microtubules
Also help provide shape and support
Main component in cilia and flagella
Move liquids across cell membrane
Video Clip 1
Video Clip 2
Video Clip 3
Video Clip 4

12. Other organelles… Centrioles Cilium Flagella
Move chromosomes when the cells divide
Produce microtubules
Cilium
Short hairlike extensions made of microtubules found on a cell’s surface
Function as a group (up to 50,000) to move the cell
Flagella
Long whip like structure that is made of microtubules
Found singly or in pairs like a tail
Moves the cell

13. Cellular Organisms What are multicellular organisms?
Any organism made of two or more cells
What are unicellular organisms?
Any organism made up of only one cell
What is cell specialization?
The development of a cell for a particular life function
Needed for multicellular organisms to have separate organs and tissues
Video Clip 1
Video Clip 2

14. Cell Specialization Tissues Organs Organ systems Organism
Group of cells that are alike in structure and activity
Organs
Collection of tissues that work together to perform a specific function
Organ systems
Several organs that work together to perform an activity
Organism
Group of organ systems that form one body