Prokaryotic Cells Flashcards
How old are prokaryotic cells?
3.5 billion years ago
Do prokaryotic cells have a nucleus?
No just circular DNA
Are prokaryotic cells biochemically diverse?
Yes
When did eukaryotic cells develop?
2 billion years ago
What groups can prokaryotes be divided into?
Bacteria and Archaea
What does the cytoplasm of prokaryotic cells contain?
Ribosomes
What are flagella composed of?
Protein Flagellin
What is the purpose of Pili?
Help bacteria stick to their substrate
What is the role of prokaryotic cell wall?
Protects cell against mechanical and osmotic shocks
What is a prokaryotic cell wall composed of?
Peptidoglycan
What is gram positive bacteria?
Part of the wall which has a 40nm layer of peptidoglycan
What is a gram negative bacteria?
Part of the wall with a complex cell wall structure which are more dangerous to humans
What is a photoautotroph?
Photosynthetic organism which use light to synthesise organic compounds from carbon dioxide
What is a chemoautotroph?
Use carbon dioxide as a carbon source and obtain their energy by oxidising inorganic substances
What is a photoheterotroph?
Use light to generate ATP but must obtain their carbon in an organic form
What is a chemoheterotroph?
Use organic molecules to supply both carbon and energy
Are viruses alive?
No
Can viruses self repair?
No
What microscope are viruses visible on?
Electron
What are features of Filamentous viruses?
Nucleic acid is arranged in a helix, with the protein sub units surrounding and stabilising it eg Tobacco mosaic virus
What are Spheroid viruses?
Nucleic acid is condensed inside a protein envelope
Organised into a multisided geometric shape
What are Tailed Spheroid viruses?
Spheroid virus with a tail
What are enveloped viruses?
Spheroid virus but with lipoprotein coat
What are the features of ebola?
Filamentous
single stranded RNA virus with variable length branches morphology
Helical capsid is enclosed inside a membrane
What are the 4 modes of nutrition among prokaryotes?
Photoautotrophs
Chemoautotrophs
Photoheterotrophs
Chemoheterotrophs