Unit 1: Introduction to the Cell Flashcards
He discovered cells while looking at a thin slice of cork
Robert Hooke
(1665)
He used a handmade microscope to observe animalcules in pond scum and various specimens
Anton van Leeuwenhoek
(1673-74)
He said that cells are found both in animals and plants
Anton van Leeuwenhoek
(1673-74)
A once widely accepted belief as to the origin of organisms
Spontaneous Generation
He discovered the nucleus, an opaque spot in cells
Robert Brown
(1831)
The random motion of particles resulting from their collision with the fast-moving atoms or molecules in a medium
Brownian Motion
He coined the term protoplasm to describe the contents of a cell
Johannes Purkinje
(1839)
He concluded that all plant parts are made up of cells; He is a cofounder of the cell theory
Matthias Schleiden
(1838)
He concluded that all animal tissues are made up of cells; He is a cofounder of the cell theory
Theodor Schwann
(1839)
He stated that cells originate from other preexisting cells
Rudolph Virchow
(1955)
He demonstrated the first evidence of cell division
Rudolph Virchow
(1955)
The statement of Rudolph Virchow as to the concept of cells arising from preexisting cells
Omnis cellula e cellula
The 3 statements of Cell Theory
- All organisms are composed of cells (Schleiden and Schwann, 1839-39)
- Cells are the smallest living things (Schleiden and Schwann, 1839-39)
- Cells arise only from preexisting cells (Virchow, 1955)
The 3 structures common in all cells
- Genetic Material
- Cytoplasm
- Plasma Membrane
The 4 additional statements of Cell Theory
- Cells pass on information during cell division using DNA
- All cells have the same chemical composition and metabolic activities
- All cells have the same chemical and physiological functions
- Cell activity depends on the activities of its structures
Microscopes that can resolve structures 200nm apart
Light Microscopes
Microscopes that can resolve structures 0.2nm apart
Electron Microscopes
A region of the cytoplasm where a prokaryote’s genome (DNA) is located
Nucleoid
A small extra piece of chromosome in prokaryotes
Plasmid
Also known as protoplasm, a gel-like substance that contains cell structures and processes
Cytoplasm
Bacteria’s storage for nutrients
Granules
A structure that separates the cell from its environment
Plasma Membrane
Bacteria with thick peptidoglycan cell walls
Gram-positive
Bacteria with thin peptidoglycan cell walls
Gram-negative
