11. Which of the following organism(s) produce(s) tetracycline?

A. Streptomyces aureofaciens
B. Steptomyces ramosus
C. Nocardia sulphurea
D. All of these

12. Media used for the production of chlortetracycline consists of

A. sugar, corn steep liquor, CaCO₃, (NH₄)₂SO₄and NH₄Cl
B. corn steep liquor, CaCO₃and (NH₄)₂SO₄
C. sugar, CaCO₃and (NH₄)₂SO₄
D. corn steep liquor, CaCO₃, (NH₄)₂SO₄and NH₄ Cl

13. Which of the following precursor is added in the medium to get penicillin G?

A. Phenyl carbamic acid
B. Phenylacetic acid
C. Ammonium sulfate
D. Ammonium chloride

14. High yield of chlortetracycline requires

A. no aeration
B. continuous aeration
C. aeration which does not affect the yield
D. controlled aeration

15. Streptomycin is produced by

A. S. griseus
B. IS. griseofulvin
C. S. aureofaciens
D. S. ramosus