Prokaryotes

• What is a clade ?

  A group of organisms that includes an ancestor and all of its descendants.
• Prokaryotes lack nuclei and cellular organelles.
• Prokaryotic cells have cell walls made of peptidoglycan. and circular cromosomes
• Reproduce via binary fission
• Cell walls help prokaryotes in avoiding harm
• In bacteria: DNA is found in the cytoplasm and is not enclosed in a nucleus.
• In bacteria endospores can be formed, this preserves the cell's genetic material in times of extreme stress. And can remain dormant until conditions improve.
• Most motile bacteria use flagella to move around, but some use pili to attach to surfaces
• How is binary fission different from mitosis ?

  There is no spindle, no centrioles
• How can they adapt without sexual reproduction?

  Mutations (because of the large populations these mutations happen often) Combination
• Vertical gene transfer: The transfer of genetic information during reproduction from one generation to the next through the gametes
• Horizontal gene transfer is the transfer of genetic material from one organism to another by simple diffusion.
• Conjugation : Sex without reproduction, it's the genetic transfer between two individuals. One way transfer of genetic information. DNA transferred to the recipient using a structure called pilus.
• Transformation: A bacterium takes up a piece of DNA floating in its environment, often DNA shed by an other bacteria.
• Transduction: Viruses that infect bacteria move short pieces of chromosomal DNA from one bacterium to the other.
• Obligate anareobes: Organisms that are poisoned by Oxygen
• Obligate aerobes : Must use oxygen
• The first prokaryotes were chemoheterotrophs that absorbed organic molecules from the environment