An antibody is a protein that has which level of protein str
     An antibody is a protein that has which level of protein structure?  Primary  Quaternary  Tertiary  Secondary  Which cell type does the HIV infect?  Cytotoxic T lymphocytes  B lymphocytes  Helper T lymphocytes  Suppressor T lymphocytes 
  
  Solution
antibody is a protein which is in quaternary structure because it consist of more than one polypeptide chains (two heavy chain and two light chain ) joint by disulphide bond.
HIV infect Helper T lymphocyte(CD4+T cells).It causes the lower level of CD4+ cells by pyroptosis.When CD4 cell number is declined below a normal level than cell mediated immunity is lost and body become suceptible to various infection.

