PlanetofProkaryotesLEC20 Flashcards
How old is the first found amber that contain an ancient spider attack fossil?
100 million year old
What are the two kingdoms early classification systems had?
Plants & Animals
What replaced the old classification system? What are they split into? By who?
A 3 domain system: -Archaea -Bacteria -Eukarya Each one is split into many kingdoms by taxonomists.
What is a virus?
A microsopic, noncellular infectious particle that attack every kingdom of life. They do have DNA & can evolve.
In a hand full of soil, is the number of living prokaryotes greater or less than the number of people who ever live?
Greater
Where can prokaryotes thrive?
Almost everywhere, including extreme conditions.
Most prokaryotes are what? What do they remarkably have?
Unicellular
Genetic diversity
Prokaryotic cells have cell walls, and have variety of what?
Shapes.
Common shapes are spherical, rod-shaped, and spiral.
What is a fimbriae, and what does it do for prokaryotes?
Hairlike structures that allow prokaryotes to stick to their substrate or other individuals in a colony.
What is a flagella, and what does it do for most motile bacteria?
Tail-like structure similar to a sperm’s tail. It helps them propel themselves.
Many prokaryotes can move, but others can what?
Grow toward or away from stimuli in the way plants do.
How do prokaryotes reproduce?How often do they divid?
Quickly by binary fission. If conditions are good, they divid every hour.
What shape do DNA have in prokaryotes?
A long ring.
Some also have smaller rings of DNA called plasmids that can be considered independant life-forms similar to viruses.
What can horizontal gene transfer do for prokaryotes?
Speed up their evolution.
When one bacterium obtain resistence, it can quicky transfer those genes to many species of bacteria.
What can prokaryotes form, which can remain viable in harsh conditions for centuries?
Endospores
