Class 12th Biology 2016 Set3 Delhi Board Paper Solution
Question 20
Given below is a list of six micro-organisms. State their usefulness to humans.
Nucleopolyhedrovirus
Saccharomyces cerevisiae
Monascus purpureus
Trichoderma polysporum
Penicillium notatum
Propionibacterium sharnanii
Answer
Usefulnes to humans:
(1) Nucleopolyhedrovirus:
It is a biological control agent
it is a species-specific insectiside.
(2) Saccharomyces cerevisiae
It is used to ferment bread dough.
It is used in the preparation of ethanol by fermenting fruit juices and cereals
(3) Monascus purpureus:
It is used for producing statins for lowering blood cholestrol.
(4) Trichoderma polysporum:
It is used for producing cyclosporin A which is used as an immunosuppressive agent in organ transplant patients.
(5) Penicillium notatum:
Used for producing antibiotic penicillin.
(6) Propionibacterium sharnanii:
It helps in ripening of swiss cheese.It is also responsible for the appearance of large holes in the cheese, as it produces high amount of carbon dioxide.Popular Questions of Class 12th biology
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