bacteria Flashcards
what kingdom are they from
monera
what is bacteria
bacteria are unicellular organisms that are lager than viruses but also microscopic in structure
What kind of cells are Bacteria
prokaryotic cells
How do they get they food
Most bacteria are heterotrophic (can manufacture own food).
Some are autotrophic (can manufacture own food)
Is bacteria harmful
Yes and no
Some are pathogenic ie. They are disease causing.
But most are useful to the environment and to humans
Bacteria can be classified into three groups acc to how they obtain they energy
Name and explain them
• Photosynthetic bacteria: utilise radiant energy from the sun.
• Chemosynthetic bacteria: obtain energy from the breakdown of chemical compounds.
• Heterotrophic bacteria: feed on organic matter to release energy.
Describe the nucleus of bacteria
And explain where the dna is found
Bacteria do not have a clearly defined nucleus.
The DNA is confined to one area called the nucleoid.
DNA also occurs freely in the cytoplasm in the form of circular molecules of DNA called plasmids.
List the general characteristics of bacteria
• Bacteria are unicellular, prokaryotic organisms from the kingdom of Monera
• They have no membrane around the nuclear material and therefor are prokaryotic
They occur in different shapes
Bacteria can be autotrophic or heterotrophic
mutualistic, parasitic or saprophytic
Bacteria reproduce very rapidly by binary fission
Explain the different shapes bacteria can be found in
coccus - round
bacillus - rod-shaped
spirillum - spiral-shaped
vibrio - comma-shaped
How does bacteria reproduce
Reproduction is asexual and occurs through the process of binary fission (mitosis) during favourable conditions (sufficient food, water, space; correct temperature, pH; lack of toxins).
Explain the process of binary fission
