Fill in the blanks :
(i) External defence also called …………and internal defence also called ………..are the types of non-specific defence mechanism of the human body against microbes.
(ii) ………….and ……………are called the soldiers and scavengers of the body.
(iii) An antiviral protein called ..........is released by the ...........infected cells. The latter makes nearby uninfected cells more resistant to infection.
(iv) The immune system comprises ..........cells and ............cells.
(v) Tears are secreted by ..........glands and contain an enzyme .............to fight eye infection.