1. Chapter 7
Cells and Organelles

2. Background Every living thing is made of cells
Robert Hooke coined the term “cells”
Antonie van Leeuwenhoek discovered the first living cell

3. The Cell Theory states that:
All organisms are composed of one or more cells.
The cell is the basic unit of organization in all organisms.
All cells come from pre-existing cells

4. Levels of organization
Smallest living unit is the cell
Cells
Tissues
Organs
Organ
System

5. Two types of cells Types of cells Prokaryotes – simple cells, bacteria
Eukaryotes – complex cells, animal and plant
We will go over move differences later…

6. Inside the cell there are smaller parts called organelles
Organelle means little organ

7. Plasma Membrane
The plasma membrane, aka the cell membrane, surrounds the cell
It is present in all cells
Function – controls what enters and leaves the cell
Selectively permeable – selects what moves through it

8. Plasma membrane
Structure
Phospholipid bilayer
Proteins
Carbohydrates

9. Cell Wall Surrounds some cells Though and ridged Made of cellulose
Plant cells, fungi cells, and bacteria cells
Though and ridged
Made of cellulose

10. Nucleus Controls everything in the cell
Reproduction, movement, eating
Only present in eukaryotic cells
Contains all genetic information

11. Surrounding the nucleus is the nuclear envelope
Inside the nucleus is the nucleolus
The nucleolus produces an organelle called the ribosomes

12. Ribosome Ribosomes are the site of protein synthesis
Found all over the cell

13. Endoplasmic Reticulum
Two types: smooth and rough
Smooth – stores lipids
Rough – after the ribosomes make proteins the rough ER packages them in vesicles to move around, or out of, the cell
Rough because it is covered in ribosomes

15. Golgi Apparatus
Modifies proteins before they are sent out of the cell

16. Production of Proteins
Each organelle has a role to play in the production of proteins

17. Vacuole Main function is storage
In both plant and animal cells, but they are much larger in plant cells

18. Mitochondria Produces energy for the cell
Does this through a process called cellular respiration
Many folds to increase surface area
Why?

19. Chloroplast Produce sugar, or food, by using light energy
This process is celled photosynthesis
Found in plant cells and protist cells

20. Lysosome
The lysosomes job is to digest things that are no longer needed by the cell
Contain special enzymes to do this

21. Different types of cells

22. Animal v Plant Cells

23. Different types of cells

24. Stem cells Eukaryotic organisms begin as a mass of cells
Each cell has the same DNA so how do we end up with hundreds of cell types?
It has to do with the DNA!

25. Stem Cells
Cell differentiation is when these cells become different. When this happens only specific parts of the DNA are activated.
the parts of the DNA that are activated determine the function and specialized structure of a cell.
Once a cell is differentiated it cannot be reversed.
So what does this have to do with stem cells?

26. Stem Cells Stem cells have not differentiated yet
They have the ability to become any cell!
Embryonic stem cells – found in the embryo
Adult stems cells – found in adult living organisms (example – bone marrow)
Both types have potential to be come specialized cells
Why is this important?? How can it be useful??