Prokaryotic and eukaryotic cell Flashcards
What are the names of the two families for prokaryotic cells?
Archaea and Bacteria
What are extremophiles?
Cells that are adapted to living in extremes of salinity, pH and temperature.
Were can extremophiles be found?`
Hydrothermal vents and salt lakes (similar environments to that of the early Earth).
What defines a prokaryotic cell?
It is a single-celled organism Its DNA is not contained within a nucleus They have few organelles There organelles are not membrane- bound
How is the DNA packaged in prokaryotic cells?
They only have one molecule of DNA , a chromosome, which is supercoiled to make it more compact. The genes on the chromosome are grouped into operons , meaning a number of genes are switched on or off at the same time.
How is the size or a ribosome determined?
The rate at which they settle, or form a sediment in a solution.
What are the size of the ribsosomes in a eukaryotic cell?
80S
What are the size of the ribsosomes in a prokaryotic cell?
70S
What can the larger, 80S, ribosomes do that the smaller, 70S ribosomes can not?
Form more complex proteins
What is the cell wall of prokaryotic cells made from?
Peptidoglycan (murein), a complex polymer formed from amino acids and and sugars.
How do prokaryotic cells rotate the filament that forms the flagellum?
The process of chemiosmosis
How do eukaryotic cells rotate the filament that forms the flagellum?
Through ATP
How is the flagellum is attached to the cell membrane of a bacterium?
By the basal body.
When did the first eukaryotic cell appear?
1.5 billion years ago
What is the name of the theory that states that organelles such as the mitochondria and the chloroplast were originally prokaryotes which where then taken inside another cell as a endosymbiont. This is said to be the evolution eukaryotic cells.
Endosymbiosis
