1. Structure and Function
Cells
Structure and Function

2. Cells Cont.
To be Considered alive, all organisms must be made of one or more cells.
CELL: The smallest unit of matter that can carry on all of the processes of life.

3. Cell History
The discovery of the cell was made possible via the development of the microscope in the 17th century.

4. Cell History The Year: 1665 The Person: Robert Hooke
Discovery: 1st person to observe cells (cork)
Legacy: Coined the term Cells because the cork reminded him of the living quarters of Monks and Monks lived in cells.

5. Cell History The Year:1673 The Person: Anton Von Leeuenhoek
Discovery:Independent of Hooke, Leeuenhoek was the first person to observe living cells.
Legacy: Was considered the world foremost microscope maker. He also had funny hair.

6. History Continues
Matthias Schleiden (Botanist) 1838: All Plants are made of cells
Theodore Schwann (Zoologist)1839: All animals are made of Cells
Rudolf Virchow (Physician) 1855: Cells come from other cells.

7. Cell Theory
The work of these scientists became a unified theory called the cell theory. The Theory consists of 3 parts.
1. All living things are composed of one or more cells.
2. Cells are the basic units of structure and function.
3. Cells come from pre-existing cells

8. Cell Diversity
Size: 6.5 ft (nerve cell giraffe) in (bacteria)
Most Plant and animal cells are about .002 in in diameter and are only visible with a microscope.
What limits a cells Size?
Surface area to volume. This controls the rate at which a cell receives nutrients

9. Cont.
Cell Shape : Cells can be a variety of shapes. Most often the shape of the cell depends upon the function.

10. Internal Organization
All Cells Contain Organelles.
Organelle: A Component that performs a specific function for the cell.

11. Prokaryote vs Eukaryote
Two Types of Cells
Prokaryote: Unicellular organisms that lack a membrane bound Nucleus as well as other organelles.

12. Cont.
Eukaryote: Organisms that contain a membrane bound nucleus.

13. Eukaryotic Structures
Cell Membrane
A. Separates the cytoplasm of the cell from its environment
B. Protects the cell & controls what enters and leaves
C. Cell membranes are selectively permeable only allowing certain materials to enter or leave

14. Cell Membrane Cont.
D. Composed of a lipid bilayer made of phospholipid molecules That are amphipathic.
Amphipatic: Both Water Loving and Fearing in One Model.

15. Fluid Mosaic Model

16. Membrane Proteins
Peripheral Proteins: Located on Either Surface Of The Membrane. Important in Molecular Transport Through The Membrane.
Integral Protein: Goes Through The Membrane. Form Ion Channels or Pores For Transport.

17. Cont.
Carbohydrate: Serves as an anchor or a receptors for bacteria or viruses. Can also be used by medicine.
Steroids (Cholesterol): Structure and support.
Phospholipids: Structure and support. Main Component of Membrane.

18. The Nucleus Often Called The Brain…ehhhhh The most prominent organelle
The Nuclear Envelope, which surrounds the nucleus, is a double membrane.

19. Nucleus Cont.
The Envelope has holes (Pores) in it to allow for things to enter and leave the Nucleus
Contains the genetic information in the form of Chromatin or Chromosomes.
Contains the Nucleolus which is a region in the nucleus that partially assembles ribosomes.

20. Mitochondria
Mitochondria are the site for chemical reactions that create Energy.
The # of Mitochondria depends upon the energy requirement for that cell (Can be up to 2500 per cell….Liver)

21. Cont. The Mitochondria has a double membrane.
Outer Membrane is smooth and serves as a barrier
Inner membrane (Cristae) is folded and is the site of Energy production.
Why is it folded?
Increase surface area, in crease chem rxn and increase energy output.

22. Cont. Mitochondria also contain their own DNA.
The DNA is Maternal and is often used in tracking missing persons or identifying soldiers

23. Endoplasmic Reticulum
Considered to be the highway system of the cell.
Used in transporting things around the cell.
There are two types:

24. Rough ER Rough ER is studded with ribosomes.
Its called Rough because the ribosomes make it look…….ROUGH (DUH).
Its main function is to produce protein

25. Smooth ER The Smooth ER is not Studded with Ribosomes.
Since it is not Studded with Ribosomes it is considered to be smooth.
Functions in making cell membrane lipids (Fats).

26. Golgi Apparatus This is the UPS of the cell for the following reasons:
It receives products produced by the cell
It modifies those products (packages)
It sends the packaged products to their final destination

27. Cilia
Cilia are short hair-like projections that are used most often to propel the cell.
Used in cellular movement mainly by single celled organisms.

28. Flagella Long Whip-like tail used by cells to to propel themselves.
Used mainly in single celled organisms.