prokaryotic cells + viruses

includes replication x

what is a bacterial cell wall made up of?

murein (peptidoglycan)

list 8 ways in which prokaryotic cells differ from eukaryotic cells

• much smaller

• 'cytoplasm lacks membrane bound organelles

• smaller ribosomes (70S)

• no nucleus - instead have a single circular DNA molecule which is free in the cytoplasm and not associated w/ protein

• murein cell wall

• have 1≤ plasmids (some)

• have a capsule surrounding the cell (some)

• have 1≤ flagella (some)

what are the 3 main structural components of a virus?

• genetic material

• capsid

• attachment protein

  

give 3 structural features found in all virus particles and describe their function":

• capsid - protects genetic material

• genetic material - codes for viral protein

• attachment protein - to bind to receptors on cell

name the 7 key structural components of a general bacterial cell

• flagellum

• genetic material (circular and plasmids)

• cytoplasm

• ribosomes

• capsule

• murein cell wall

• cell membrane

describe the process of binary fission:

• circular DNA and plasmids replicate (main DNA loop only replicated once but plasmids can be replicated many times)

• cell grows and DNA loops move to opposite poles of cell

• cytoplasm begins to divide and new cell walls begin to form

• cytoplasm divides and 2 daughter cells are produced w/ 1 copy of circular DNA but a variable no. of copies of plasmids

how do viruses replicate themselves (generally)?

• use attachment proteins to bind to complementary receptor proteins on cell surface membrane

• inject DNA/RNA into host cell - organelles help to replicate viral particles

why are viruses described as acellular and non living?

• not made of cells/no cell surface membrane

• no metabolism/nutrition

• cannot independently move/respire/replicate/excrete

give one reason why antibiotics are ineffective against viruses:

any 1 from:

• do not have bacterial structure/enzymes

• do not have metabolism

• do not have cell wall/murein