Lecture 1 Flashcards
When did Prokaryotes develop?
3.5 billion years ago.
When did eukaryotic cells develop, and from what?
2 billion years ago, from prokaryotic cells.
Relative mass of prokaryotes to eukaryotes?
10:1.
2 domains of prokaryotes?
Bacteria, archaea.
What domain of prokaryotes often live in extreme environments?
Archaea.
Which out of bacteria/archaea/eukarya contain a nuclear envelope?
Eukarya.
Which out of bacteria/archaea/eukarya contain membrane bound organelles?
Eukarya.
Which out of bacteria/archaea/eukarya contain peptidoglycan in cell wall?
Bacteria.
What types of membrane lipids do bacteria/archaea/eukarya contain?
Bacteria and eukarya - unbranched hydrocarbons.
Archaea - some branched hydrocarbons.
Which out of bacteria/archaea/eukarya contains more than one kind of RNA polymerase?
Archaea and eukarya.
What is the initiator amino acid for starting protein synthesis in bacteria/archaea/eukarya?
Bacteria - formyl-methionine.
Archaea and eukarya - Methionine.
Which out of bacteria/archaea/eukarya contain introns?
Archaea - some genes.
Eukarya.
Which out of bacteria/archaea/eukarya have their growth inhibited by antibiotics streptomycin and chloramphenicol?
Bacteria.
Which out of bacteria/archaea/eukarya contain histones associated with DNA?
Archaea and eukarya.
Which out of bacteria/archaea/eukarya contain a circular chromosome?
Bacteria and eukarya.
Which out of bacteria/archaea/eukarya can grow at temps over 100ºC?
Some archaea.
What are pili composed of? And what do they assist?
Pilin. Assist bacteria in sticking to their substrate or each other.
Many bacteria secrete a capsule. What does it contain?
Polysaaccharides.
Do some prokaryotes have flagella? What protein is it composed of?
Some do, composed of flagellin.
What does the bacterial cell wall do?
Protect cell against mechanical and osmotic shock.
What is the bacterial cell wall composed of?
Peptidoglycan.
2 types of bacterial cell wall?
Gram positive, Gram negative.
How thick is gram positive cell wall?
40nm layer of peptidoglycan.
Is the gram negative or gram positive cell wall more complex?
Gram negative.
Which bacterial cell wall typically resembles the more dangerous and harder to kill bacteria, gram positive or gram negative?
Gram negative bacteria.
3 examples of gram negative bacteria and what they cause?
Chlamydia trachomatis - blindness.
Vibrio cholerae - cholera.
Yersinia pestis - plague.
3 examples of gram positive bacteria and what they cause?
Clostridium tetani - tetanus.
Clostridium botulinum - botulism.
Streptococcus pneumoniae - pneumoniae.
Structure of gram negative cell wall from top to bottom?
Outer membrane with peptidoglycan proteins, periplasmic gel with peptidoglycan proteins.
What drug is produced bacterially at Lancaster related to Alzheimers?
β-amyloid.
4 modes of prokaryotic nutrition?
Photoautotrophs,
Chemoautotrophs,
Photoheterotrophs,
Chemoheterotrophs.
What are photoautotrophs and chemoautotrophs?
Photoautotrophs: Photosynthetic organisms using light to synthesise organic components from CO2.
Chemoautotrophs: Use CO2 as a C source, obtain energy from oxidising inorganic substances. - certain prokaryotes only.
What are photoheterotrophs and chemoheterotrophs?
Photoheterotrophs: Use light to generate ATP, but must obtain carbon organically. - certain prokaryotes.
Chemoheterotrophs: Use organic molecules for both C and energy.
Why are viruses not considered to be alive?
Can’t self-repair and don’t have an energy transduction system.
What is a complete viral particle called?
What is a virus’ protein coat called?
Viron.
Capsid.
What is the capsid made of?
Number of protein units called capsomers.
3 most common shapes of bacteria?
Cocci (spherical),
Bacilli (rod-shaped),
Spirochetes (helical).
4 shapes of virus, with an example of each?
Filamentous - Tobacco mosaic virus.
Spheroid - Adenovirus.
Tailed spheroid - Lambda phage.
Enveloped - Influenza virus.
Describe filamentous virus.
Nucleic acid arranged in a helix, protein sub-units surrounding and stabilising it.
Describe spheroid virus and tailed spheroid virus.
Nucleic acid condensed in a protein envelope - usually organised into multisided geometric shape.
Tailed spheroid same with a tail.
Describe enveloped virus.
Like spheroid virus but with lipoprotein coat.
What type of virus is ebola?
Filamentous, single-stranded RNA.
Helical capsid enclosed inside membrane.
