The Cell Theory and Microscopes Flashcards
Who named the cell and what did he observe?
Robert Hooke, cell walls of cork tissue
When was the cell named?
1665
What term did Robert Hooke coin?
Cellulae
Who created the first microscope?
Anton Van Leeuwenhoek
What and when did Leeuwenhoek base his observation of unicellular organisms on?
Protozoa (1673), Bacteria (1683)
What term did Leeuwenhoek coin?
Animalcule
What is the “Brownian motion”?
Pollen grains in water that jiggled around
Who discovered the nucleus?
Robert Brown
When and who proposed that cells are the fundamental units of plants?
1838, Matthias Schleiden
When and who proposed that cells are the fundamental units of animals?
1839, Theodor Schwann
Who were the credited founders of The Cell Theory?
Schleiden and Schwann
Who stated “omnis cellula a cellula” and what does it mean?
Rudolph Virchow, all cells arise from pre-existing cells
What is The Cell Theory?
- All organisms are made of cells.
- Cells are the smallest structural and functional unit of an organism.
- All cells arise from pre-existing cells.
What are viruses?
Viruses are not composed of cells but consist of a nucleic acid in a protein coat, yet it conducts all the cell processes (although with help).
What is the main use of a microscope?
To produce an enlarged image of an object.
What type of microscope is used when specimen is mounted on glass?
Compound Light Microscope
What microscope is used to study live specimen?
Compound Light Microscope
What microscope provides 3D imaging?
Scanning Electron Microscope (SEM)
When using SEM, what type of coating is used to spray the surface?
Fine metal coating
Are the specimens sliced for viewing in SEM?
No
How does a SEM produce an enlarged image?
SEM uses electron beam and fluorescent screen or photographic plates.
What is the maximum magnification of SEMs?
100,000x magnification
How does a TEM produce an enlarged image?
TEM uses a beam of electrons on a very thinly sliced specimen placed on a fluorescent screen or photographic plate.
What is the maximum magnification of TEMs?
200,000x magnification
What type of microscopes cannot be used to view live specimens?
Scanning and Transmission Electron Microscope
ATP
Adenosine triphosphate
