Heaphy Flashcards
What is transduction?
Phage (virus) dependent transfer, the genetic information of an infected cell can become degraded as the viruses replicate, causing some new phage to mistakenly encompass the bacterial DNA
What are the two bacteriophage life cycles?
Temperate - Phage protein repressed so the viral chromosome replicates harmlessly as the bacterial chromosome replicates
Virulent - Lytic cycle where infection quickly gives rise to a large number of genetically identical clones
What is the order of classification of organisms
Domain, Phylum, Class, Family, Genus, Species
What is conjugation?
F+ plasmid proteins are needed for this process. It is copied and passed through a sex pilus to another cell and some of the donor cell’s genome goes along with it
What is the smallest free living bacterial genome?
Mycoplasma genatalium
What is transformation?
Uptake of DNA from dead/degraded bacteria
What family do viruses belong to?
Viridae
What are transposable elements? What are the simple and complex forms called?
DNA that are able to move between other DNA molecules. Simplest form are insertion sequences, complex form are transposons
What is the progressive theory of the origin of viruses?
Viruses are normal cellular nucleic acids that developed the ability to replicate autonomously
What are the steps of viral infection?
Attachment Penetration Uncoating and incorporation of genetic information Assembly Exit
Name an example of a virus with a lipid bilayer coating
HIV
What are the types of capsid that a virus could have?
Helical or icosahedral
What does pleomorphic mean?
Able to change shape
What two techniques are used to determine viral structure?
Electron microscopy and X-ray crystallography
What does the capsid protect the virus from?
Physical damage
Chemical damage e.g. UV radiation or enzyme breakdown
Advantages of capsomeres
Self-assembly is easier with identical subunits
Using smaller proteins reduces the chances of error and if an error does occur it’s unlikely to have an extensive effect
The virus becomes more stable as subunits are added
What is pathology?
The study of disease
What microorganism causes cholera?
Vibrio Cholerae
Where do T lymphocytes and B lymphocytes mature?
T lymphocytes - Thymus
B lymphocytes - Bone marrow
What causes TB?
Mycobacterium Tuberculosis
What is the difference between curds and whey?
Curds are the solid protein and fat portions, the whey is the liquid portion
What is the definition of fermentation?
When the reductant and oxidant redox couple are both organic
What is a genome?
All the cellular DNA in an organism
What are the stages of a measles infection?
1) Contact
2) 10 day incubation period
3) Prodromal period with general symptoms
4) Acute phase with more specific symptoms e.g. rash
5) Crisis – overheating
6) Decline – sweating
7) Convalescence – back to normal
Which two species acidify and ferment milk?
Streptococcus Cremoris and Streptococcus Lactis
What organism does TAQ polymerase come from?
Thermus Aquaticus
What are the stages of PCR and the temperatures they are carried out at?
Denaturation
Annealing
What does Cas9 come from?
Streptococcus Pyogenes
What makes Quorn?
Fusarium Venenatum
Cryptosporidium and T.gondii are what?
Coccidia
What are in T.gondii cysts?
Bradyzoites
What is a chemoautotroph?
An organism which derives energy from the oxidation of inorganic compounds.
What does a lithotroph use?
Inorganic chemicals
Fact about positive sense RNA
They can be directly infectious
Untranslated regions at the 5’ and 3’ ends
5’ mehylated nucleotide cap
3’ poly-A tail
Fact about negative sense RNA
Have to have their own RNA polymerase
Segmented - many separate strands
What is a medium sized DNA virus called?
Lambda
What does cholera cause
Exhaustive diarrhoea and vomiting
