Euks/proks/archaea Flashcards
types of cellular organisms
eukaryotes
prokaryotes
archaea
dna in bacteria
single celled chromosome, may have circular plasmids
benefit of plasmids in bacteria
may contain genes that have adaptive value under certain environmental conditions
do bacteria have membranes?
only ones that separate extracellular and intercellular processes- no membranes surrounding organelles unlike in euks
sizes of bacteria?
smallest are around 200-300 nanometres, some are around 1-2 micrometres
benefit of small size of bacteria?
more effective diffusion because to surface area to volume ration is smaller, so the molecules do not have to travel far to reach the cells interior
size of genomes- euks v proks
proks have smaller genome and lack the large stretches of non coding dna found in euks
conjugation and bacteria
when two bacteria are drawn together and dna flows between each cell- this is done by membrane bound pili, which contracts
how bacteria can diversify
- replication is mostly from parent to daughter cell
- conjugation
- transformation
- horizontal gene transfer
transformation and bacteria
dna from other bacteria cells can be taken up by other cells
horizontal gene transfer and bacteria
viruses can sometimes integrate their dna into the host bacteria’s dna- called transduction
HGT is the movement of dna from one organism to another
are archaea eukaryotic or prokaryotic?
prokaryotic
do archaea have membrane bound nuclei?
no
minimum requirements for a cell to function
plasma membrane
cytoplasm
dna
ribosomes
Where is dna located in bacteria?
the nucleoid region but there is no membrane surrounding it
