viruses topic Flashcards
what are fungi cell walls made of?
chitin
what component does fungi not have?
chloroplasts - they don’t photosynthesise
role of the cell wall in bacteria?
physical barrier that excludes certain substances and protects against mechanical damage and osmosis lysis
role of the capsule in bacteria?
protects bacterium from other cells and helps groups of bacteria to stick together for further protection
role of circular DNA in bacteria? (not true nucleus)
possesses the genetic information for the replication of bacterial cells
role of plasmids in bacteria?
small circles of DNA - possess genes that may aid the survival of bacteria in adverse conditions e.g. produce enzymes that break down antibiotics (give cells useful functions like antibiotic resistance)
role of the CSM in bacteria?
acts as a differentially permeable layer which controls the entry and exit of chemicals/substances
name the components of a bacteria cell?
capsule, cell wall, plasma membrane, cytoplasm, plasmids, ribosomes, circular DNA
how to prokaryotic cells replicate?
binary fission - produces two daughter cells
why is it hard to treat viral infections?
some viruses remain asleep in our bodies and periodically awaken and cause harm, viruses reproduce so rapidly that they have the opportunity to change their genetic stripes - allows them to develop resistance to drugs, they can genetically change so their attachment proteins are different
what components do viruses have?
attachment proteins, lipid envelope, capsid, reverse transcriptase (enzyme), genetic material (DNA or RNA)
how do viruses cause damage?
attachment proteins bind to receptor proteins (antigens) on the host cell surface - cause damage by taking over and using the cell machinery for viral replication
