Microbiology part two Flashcards
(24 cards)
What are protozoa?
They are a diverse group of eukaryotes, found in water, found in water, soil, animals, humans and insects.
Protozoa are classified by the way they move, what does Amoeba mean?
it means they move by pseudopodia (feet)
Protozoa are classified by the way they move, what does Flagellates mean?
They move by flagella
Protozoa are classified by the way they move, what does Cilliates mean?
they move by cilia
Protozoa are classified by the way they move, what does Sporoza mean?
they are non motile
What are the two forms of protozoa?
reproductive trophozoite and resting/infectious agent
Some protozoa are parasites which break down and absorb nutrients from the body of the host, what are two things they don’t do?
- don’t respond to antibiotics
- don’t grow on agar
What is a virus?
A virus is a piece of DNA or RNA that requires a host cell to reproduce. They are Acellular
How big are viruses?
they range from 10-30 nanometers (very small!!)
How do we see viruses as they are too small to be seen through a light microscope?
Through an electron microscope
What are the three main shapes of a virus?
- Helical
- Icosahedral
- complex
Why are viruses not considered living?
they can’t exist in an inert state outside of a host cell
What is the structure of a virus?
- they consist of a nucleic acid (DNA or RNA), surrounded by a protective protein coat (the caspid).
sometimes they have a lipid membrane (envelope) surrounding the protein and can have a tail.
What are the viruses that infect bacteria called?
Bacteriophages or phages
How do bacteriophages work?
Phages use their end plates, tail fibres and spikes to attach to bacteria before injecting their DNA into the host cell.
What is the difference between a virulent phage and a temperate phage?
- Virulent phages lyse the host cell after producing new phages
- Temperate ones do not
What is the virus life cycle? (4 steps)
- attachment
- penetration and uncoating
- mRNA synthesis
- Protein synthesis
Why can’t viruses grow on agar? and how are they tested as a result?
- it is because they are parasites that require the machinary of a eurkaryotic cell to provide their energy and reproduction. As a result testing is done by cell culture
Can viruses be killed by antibiotics? Why or why not?
- no
- they dont have cell walls
What are fungi?
microbes (mostly), eukaryotes
What are the five different branches of fungi and an example of each?
- Chytrids ( yeast)
- Common molds ( bread mold)
- Sac fungi ( truffles)
- Club fungi (mushrooms)
- Imperfect fungi ( penicillum)
What does mycelium refer to?
- the mass of growth of the hyphae which have interwined into an observable mass.
what are hyphae?
molds are filamentous fungi and have many individual filaments which are called hyphae
Disease caused by fungi are called ? and what can they be?
Mycoses and they can be superficial, cutaneous, subcutaneous or systemic
