Chapter 3 Flashcards
The theory of spontaneous generation
Life can arise from non-living matter
Francesco Redi’s experimental setup (1668)
A container, a container sealed with a cork top, and a container covered in mesh that let in air but not flies.
How did Louis Pasteur refute the theory of spontaneous generation?
Experimented using the unique swan-neck feature which allowed air to enter the flask but prevented the entry of bacterial and fungal spores.
What was the cell theory popularized in an 1855 essay entitled “Cellular Pathology.”
All cells arise from cells
The Endosymbiotic Theory
Mitochondria and chloroplasts are each derived from the uptake of bacteria. These bacteria established a symbiotic relationship with their host cell that eventually led to the bacteria evolving into mitochondria and chloroplasts.
Why were mothers more likely to die in hospitals than when treated by midwives?
Due to lack of handwashing by staff after touching infected bodies.
The Germ Theory of Disease
Handwashing to prevent transfer of disease between patients by physicians.
What does the cell theory state?
The cell is the fundamental unit of life.
What are the 4 basic cell components?
Cytoplasm (a gel-like substance composed of water and dissolved chemicals needed for growth)
Plasma membrane/cell membrane/cytoplasmic membrane
One or more chromosomes (genetic information of the cell)
Ribosomes: the production of proteins.
What does a typical prokaryotic cell contain?
A cell membrane, chromosomal DNA that is concentrated in a nucleoid, ribosomes, and a cell wall.
What is a coccus cell shape?
Perfectly round
What are the different arrangements of the coccus cells?
Coccus - single coccus
Diplococcus - pair of two cocci
Tetrad - grouping of 4 cells arranged in a square
Streptococcus - chain of cocci
Staphylococcus - cluster of cocci
What is a bacillus shape?
A straight rod
What are the arrangements of bacillus cells?
Bacillus - single bacillus
Streptobacillus - chain of rods
What is a vibrio shape?
A curved rod.
What is a coccobacillus shape?
A short rod
What is a spirillum shape?
A loose spiral
What is a spirochete shape?
Long, helical spiral
What is an isotonic solution?
Solute concentration is equal inside and outside of the cell. No net movement of water.
What is a hypotonic solution?
Higher solute concentration inside the cell. Net water movement into the cell.
What is a hypertonic solution?
Lower solute concentration inside the cell. Net water movement out of the cell. Causes crenation.
Crenation versus plasmolysis
Crenation - animal cells
Plasmolysis - plant cells
What is the nucleoid?
Condensed area of DNA found within prokaryotic cells.
How are prokaryotic chromosomes described?
Circular, haploid (unpaired), and not bound by a complex nuclear membrane.
What is the number for ribosomes in prokaryotic cells?
70S (30S & 50S)
What is sporulation?
The process by which vegetative cells transform into endospores.