Question

define the terms: (1)antibiotics, (2)food preservation and (3)nitrogen fixation

Answer 1

here is your required answers ;

→ Antibiotics :
----------------------------------------------

Antibiotics are the Substances produced by certain fungi and bacteria, which kill micro- Organisms and stops the growth of special or particular bacteria.


→ Food preservation :
--------------------------------------------------

Food preservation is the process by which perishable food materials are preserved to prevent their spoilage and to retain their nutritive value for long periods.


→ Nitrogen Fixation :
--------------------------------------------------

wheat and rice use up large amounts of nitrogen from soil. legumes fix atmospheric Nitrogen ( Converting free nitrogen into it's compounds is called Nitrogen fixing ). This increases the Nitrogen content of the soil.


hopes it helps ^_^

Answer 2

Antibiotics are the medicines which prevent infection on the wound

Preserving (maintaing safe)food for long time is known as presarvation.
Conversion of atmospheric nitrogen into nitrated is known as nitrogen fixation