1. Life is Cellular
7-1

2. 1660’s
Anton van Leewenhoek invented the first microscope.

3. 1665
Robert Hooke used an early microscope to look at cork and named the small chambers he saw “cells.”

4. What is a cell?
Cells are the basic unit of structure and function of all living things.

5. Cell Theory 1) All living things are made of cells.
2) Cells are the basic unit of structure and function in living things.
3) New cells come from existing cells.

6. A) A cell membrane B) cytoplasm C) DNA D) ribosomes
All cells have. . .
A) A cell membrane
B) cytoplasm
C) DNA
D) ribosomes

7. A. Cell membrane A thin, flexible barrier around the cell.
Controls what enters and leaves the cell

8. B. Cytoplasm Jelly-like substance that fills the cell.
Site of many chemical reactions

9. C. DNA Stores the genetic information for the organism
Like a cookbook for making proteins

10. Use the instructions from DNA to make protein.
D. Ribosomes
Use the instructions from DNA to make protein.

11. Different types of cells
There are two types of cells:
Prokaryotic cells
Eukaryotic cells

12. How are they different? Prokaryote Eukaryote No nucleus Nucleus
No organelles
Organelles
Relatively small
Relatively large

13. Nucleus (eukaryotes) Controls the cell
Stores the genetic material (DNA)

14. What types of organisms are prokaryotes?
Bacteria

15. What types of organisms are eukaryotes?
Plants, animals, fungus, and protists (Everything except bacteria)

16. Multicellular vs. Unicellular Organisms
Multicellular – cells develop in particular ways for different functions.
i.e. humans
Unicellular – aka single celled. The one cell IS the organism.
Perform all of the functions in just one cell.
i.e yeast

18. An instrument that produces magnified images of tiny structures
Microscope
An instrument that produces magnified images of tiny structures

19. Compound Light Microscope
Most common microscope
Uses light
Compound = contains more than one lens

20. Electron Microscope More powerful than compound microscope.
Uses a beam of electrons to examine something.

21. Scanning Probe Microscope
Trace the surfaces of a sample with a tiny tip known as a probe

22. Viruses

23. What are viruses? Viruses are not cells.
They consist of DNA or RNA wrapped in a protein coat (capsid)

24. Viruses are NOT alive!!!
They inject their DNA/RNA into a cell and force it to make copies of the virus
Since they cannot reproduce on their own, they are not considered to be living.

25. Lecture Review Questions
Why was the invention of the microscope important?
How is the original definition of the cell different from today’s definition?
Virus are not living organisms, or cells, because they do not reproduce. How does their inability to reproduce go against Cell Theory?