1. The Cell Theory

2. When were the first lenses used and what was their purpose?
In the late 1500’s by merchants to determine the quality of cloth.
Who was the first person to use the microscope to study nature? (studied organisms in pond water)
Anton van Leeuwenhoek

3. In 1665, who used a light microscope to view slices of cork?
Robert Hooke
What is the basic unit of all forms of life?
the cell

4. Who, in 1839, concluded that all animals are made of cells?
Theodor Schwann
What did Rudolf Virchow discover in 1855?
Cells came from preexisting cells

5. Who, in 1838, concluded that all plants are made of cells?
Matthias Schleiden
What is the range in size of a typical cell?
1 to 100 micrometers

6. What are the three tenets of 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.

7. A thin lipid bilayer of a cell that separates the organelles of the cell from the surrounding environment.
Plasma membrane (cell membrane)
A strong fibrous layer on the outside of a plant cell made of carbohydrates and protein.
cell wall

8. A large structure in a cell that contains the cell’s genetic material and controls the cell’s activities.
the nucleus
All of the material inside of the cell membrane not including the nucleus.
the cytoplasm

9. In 1970 Lunn Margulis proposed that certain organelles were _________________________
once free living cells themselves.

10. Into what two categories do biologists divide cells?
prokaryotes and eukaryotes

11. ___________ have cell membranes and cytoplasm but do not have a nuclei.
Prokaryotes
E. coli and Staph are types of _________.
prokaryotes

12. These types of cells have a nucleus.
Eukaryotes
All plants, animals, fungi, and many microorganisms are ___________.

13. Plant cell walls are made mostly of _______, a tough carbohydrate fiber.
cellulose
The granular material visible within the nucleus is called ________.
chromatin

14. A small dense region inside of the nucleus is called the _________.
nucleolus
The assembly of ________ begins in the nucleolus.
ribosomes

15. The nucleus sends a steady stream of _____ and other information carrying molecules to the rest of the cell through the nuclear pores.
RNA
A network of protein filaments that helps the cell to maintain its shape.
cytoskeleton

16. Hollow tubes of protein that maintain cell shape and serve as tracks along which organelles are moved.
microtubules
Long, thin fibers that function in the movement and support of the cell.
microfilaments

17. Ribosomes assemble _________.
proteins
The ______________ assembles proteins and modifies them.
rough endoplasmic reticulum

18. This type of ER doesn’t have many ribosomes but is primarily responsible for synthesizing lipids for the plasma membrane.
smooth ER

19. An organelle that packages and sends proteins to their final destinations.
Golgi apparatus
Small organelles filled with enzymes that break down cell parts or other particles to be used by the cell.
lysosomes

20. Saclike structures used for storage by the cell.
vacuole
These organelles use energy from sunlight to make energy rich food molecules in a process known as photosynthesis.
chloroplasts