5.7: The human immunodeficiency virus

-Lipid envelope
-Attachment proteins
-Capsid
-RNA
-Reverse transcriptase

1. Attachment protein attaches to receptor molecule on T-helper cell

2. Viral RNA is released into the cell’s cytoplasm

3. Reverse transcriptase is used to make a complementary strand of DNA from viral RNA template

4. Double-stranded DNA produced and inserted into the human DNA

5. Host cell enzymes uses to make viral proteins

6. Viral proteins assembled into new viruses

• HIV attacks T-helper cells.
  -immune system cannot stimulate B cells to produce antibodies or cytoxic T cells

• body cannot produce an adequate immune response and becomes susceptible to other infections or cancers

enzyme linked immunosorbant essay

• Apply the sample to a surface to which all the antigens in the sample will attach

• Wash the surface to remove any unattached antigens
  -Add the antibody that is specific to the antigen

• Wash the surface to remove excess antibody
  -Add a second antibody with an enzyme attached that binds with the first antibody
  -Add the substrate of the enzyme
  The formation of an ES complex will cause colour to be released showing a positive result

• Antibiotics work by inhibiting the production of murein cell walls in bacteria
  -Viruses don’t contain murein cell walls

• Viruses rely on host cells to carry out metabolic processes
  -Antibiotics can’t reach them

ipe down surfaces with ​antibacterial cleaner,​​ both ​before and after experiment.
● Use a ​Bunsen burner​​ in the work space so that ​convection currents​​ draw microbes away from the culture.
● Flame the wire hoop​​ before using it to transfer bacteria.
● Flame the neck of any bottles​​ before using them to prevent any bacteria entering the vessel (air moves out so unwanted organisms don’t move in).
● Keep all vessels containing bacteria​ ​​open for the minimum amount of time.
● Close windows and doors​​ ​​to limit air currents.