Microscopy, Cellular Biology, Microbiology Flashcards
Who invented the first compound microscope?
Zacharias Janssen & Hans Lippsershey (independently)
- Janssen’s first microscope was telescope like and really long.
Galileo was the first to perfect the manufacture of the compound microscope. (17th century)
What were the problems with early microscopes?
Early microscopes had a small field of view and they distorted images due to uneven glass. They were initially looked at as a toy.
Marcello Malpighi
Malpighi described capillaries in the lungs and discovered kidney tubules. He studied plant anatomy based on the idea that it was similar to animal anatomy, which was a wrong conclusion.
Jan Swammerdam
Swammerdam dissected the mayfly larvae and provided a detailed internal anatomy. He also made minutely accurate dissections of frogs, honeybees, etc.
Anton van Leeuwenhoek
He perfected the single lens microscope.
- Observed sperm tissues, bacteria, hydra, compound eye of insects, etc.
Robert Hooke
- Important publication: Micrographia
- Drew the cellular structure of a cork
- First to use the word ‘cell’
- Observed the sting of nettles and bees
Nehemiah Grew
Provided a critical anatomical description of the different parts of the flower and also found vessels in stems (independent of Malpighi).
What important concepts did microscopy bring to science?
- The creation of microscopes disproved the theory of spontaneous generation
- The ‘unseen’ microscopic world was being revealed
- Starting point for fields like physiology, embryology
- It gave the term ‘cell’ more importance: initially cells were connected with plants
Johannes Purkinje
- Physiologist that coined the word ‘protoplasm’
- Foresaw cell theory before Schwann
- Listed three fundamental structures in living organisms (fibres, fluid, cells)
- Developed the use of stains
Matthias Schleiden
19th century; proposed 1st cell theory
- Said that cells crystallize out of the fluid surrounding the nuclei and then disappear. He deemed this by looking at the developing embryo sac of seed plants.
- The idea was called ‘Nucleus of crystallization’
Theodor Schwann
19th century
- His theory stated that plants and animals were composed of basically identical units. He believed the new cells arised from old ones.
- Showed that tissues were cellular in origin
- Suggested that eggs are essentially cells because they exhibit similar characteristics.
What is the theory of Preformationism and how did microscopy affect this theory?
Late 17th century
The theory that ‘animacules’ (like little versions of people) were present in semen and that was what we grow from. If you doubted this theory it was looked at as atheism.
Rudolph Albert von Koelliker
19th century
- First to recognize that ova and sperm were cells and the first to apply cell theory to embryology
- Discovered that nerve fibres were essentially elongated processes of nerve cells
- Did much to disprove that cells could arise freely (don’t arise from existing cells)
Rudolph Virchow
19th century
- Developed the cell theory into a theory of cellular pathology; ‘every pathological phenomenon occurs within cells or is derived from them
- ‘Every cell comes from a cell’
Max Schultze
Established the modern concept of the cell as a ‘nucleated protoplasm’. Protoplasm was now looked at as the physical basis of life (late 19th century) instead of being viewed as a simple liquid (early 19th century)
