Structure of prokaryotic cells and viruses

• What 4 things do ALL prokaryotes have?

  -A cell wall made of murein for strength and rigidity

  -A cell membrane which is selectively permeable made from phospholipid bilayer

  -Circular DNA to store genetic information to code for bacterial proteins

  -Smaller 70S ribosomes to produce proteins
• What 3 things do only SOME prokaryotes have?

  -A capsule made of a polysaccharide that waterproofs the cell and protects it from other cells

  -One or more flagella that allow motility

  -Plasmids which contain extra genes
• Compare and contrast the structure of eukaryotic cells and prokaryotic cells

  -Eukaryotic cells (EC) are larger than prokaryotic cells (PC)

  -EC contain membrane-bound organelles but PC don't

  -Both have cell membranes

  -PC only have 70S ribosomes but EC contain 70S and 80S ribosomes

  -DNA in EC is in the nucleoplasm but in PC, it is in circular DNA loose in the cytoplasm

  -PC contain plasmids with extra DNA but EC don't

  -EC cell wall is made of cellulose or chitin but PC cell wall is made of murein

  -PC have a flagellum and capsid but EC don't
• Define a virus

  Viruses are acellular and cannot replicate independently so need to be in a host cell
• Name the components of the structure of HIV and their function in the replication cycle

  Attachment protein - complementary and bind with T cells

  Lipid envelope - fuses with T cell membrane

  RNA genetic information - converted to cDNA

  Capsid - protein coat that protects the RNA

  Reverse transcriptase enzyme - converts RNA to cDNA