Prokaryotic Cells And Viruses Flashcards
What are eukaryotic cells?
These are larger cells that have a nucleus bounded by nuclear membranes.
What is a prokaryotic cell?
This is a small cell that has no nucleus or nuclear envelope.
What are three features of bacteria that allows them to occur in every habitat in the world?
They are versatile, adaptable and very successful.
Why are they so successful?
This is because they have a small size ranging from 0.1 to 10 micro metres in length.
What is the bacterial cell wall made of?
Murein
What is murein a polymer of?
This is a polymer of polysaccharides and peptides.
How do many bacteria further protect themselves?
They secrete a capsule of mucilaginous slime around this wall.
What is inside the bacterial cell wall?
The cell-surface membrane.
What is inside the cell-surface membrane of a bacterial cell?
Within this is the cytoplasm that contains 70 S ribosomes which are smaller than those in the cytoplasm of eukaryotic cells but nevertheless still synthesise proteins.
What do bacteria store food reserves as?
They store it as glycogen granules and oil droplets.
What is the genetic material in bacteria in the form of?
It is in the form of a circular strand of DNA and separate from this are small circular pieces of DNA which are known as plasmids.
What part of the bacterial cell can reproduce itself?
Plasmids
What are plasmids used extensively as vectors in?
Genetic engineering
Do prokaryotic cells have membrane bounded organelles?
No they don’t.
Do prokaryotic cells have a nucleus?
They have no true nucleus, they only have an area where DNA is found.
Do prokearyotic cells have chloroplasts?
They have no chloroplasts, only bacterial chlorophyll associated with the cell-surface membrane and some bacteria.
What may aid the prokaryotic cell’s survival in adverse conditions?
The plasmid.
In which type of cell is DNA associated with proteins?
Eukaryotic cell
What type of eukaryotic cells contain chloroplasts?
Plants and algae.
What are most eukaryotic cell walls made of?
Cellulose or in fungi chitin.
Are viruses living or non living?
They are non-living particles.
What do viruses contain?
They contain nucleic acids.
Where can viruses multiply?
They can only multiply inside living host cells.
What is the nucleic acid in a virus coated in?
It is coated in a protein coat called the capsid.
What are some viruses further surrounded by?
A lipid envelope.
Give an example of a virus that is surrounded by a lipid envelope.
The human immunodeficiency virus or HIV.
What does the capsid have?
Attachment proteins.
Why are attachment proteins important?
They are essential to allow the virus to identify and attach it to a host cell.
