Prokaryotes Flashcards
What is the difference between organic and inorganic carbon?
Inorganic carbon comes from geology - ores, minerals etc, whilst organic carbon originates from photosynthesis - found in plants & animals.
How do chemoorganoheterotrophs access nutrients?
Organic carbon (e.g from carbohydrates). Same strategy as all animals.
How do chemolithoheterotrophs access nutrients?
Inorganic chemicals from the environment. This strategy is only used by prokaryotes.
How do photolithoautotrophs access nutrients?
They reduce atmospheric CO2 to produce carbon for biosynthesis using inorganic electron sources.
How do chemolithoautotrophs access nutrients?
Inorganic carbon from atmospheric CO2.
Explain how plants act as photolithoautotrophs.
They photosynthesize, reducing atmospheric carbon using water as their inorganic electron source.
How does a photoorganoheterotroph access nutrients?
Use light as their energy sources but gain carbon and electrons from organic carbon sources - cannot source entirely from atmospheric CO2.
Do bacteria carry out meiosis?
No
How do bacteria evolve and introduce genetic diversity if not by meiosis?
Horizontal gene transfer
Name and explain the 3 modes of horizontal gene transfer in bacteria.
Transformation (DNA from dead bacteria released and taken up by another).
Transduction (DNA is transferred between bacteria by viruses)
Conjugation (transfer of DNA through cell-to-cell contact and conjugation bridge).
In what ways are bacteria and archaea (both prokaryote groups) different?
Slightly different cell membrane structure and make-up. Archaeal DNA replication more closely resembles that of eukaryotic cells, as do their transcription and translation machinery.
What shapes do prokaryotes exist in?
Bacillus (rod shaped), coccus (spherical or oval) and spirillum (long and helical).
In what ways are prokaryotes beneficial?
