Cut surfaces of fruit and vegetables often become dark because
(a) dirty knife makes it dark
(b) oxidation of tannic acid in the presence of a trace of iron from the knife makes it dark
(c) dust of the air makes it dark
(d) none of the above
Cotton fibres mainly contains
(a) cellulose (b) glycogen
(c) protein (d) lipid
Which of the following sugars is not found in plants?
Jute fibres deteriorate quickly because
(a) cellulose content is high
(b) lignin content is high
(c) cellulose content is low
(d) lignin content is low
In a 50 gm living tissue, what would be the amount of water?
(a) 15-25 gm (b) 25-30 gm
(c) 35-45 gm (d) 70-90 gm
Which of the following elements is present in very less quantity in the body?
(a) K (b) Ca
(c) Mg (d) Cu
In a normal adult, ascending order of concentration of following molecules is
(a) K>Na>Fe>Cu (b) Na>K>Cu>Fe
(c) Fe>Na>K>Cu (d) Na>Fe>K>Cu
Select the option having all correctly matched pairs.
A. Alkaloids (i) Carotenoid; Anthocyanin
B. Pigments (ii) Vinblastin; curcumin
C. Drugs (iii) Morphine; Codeine
(a) A-i;B-ii;C-iii (b) A-ii;B-iii;C-i
(c) A-iii;B-i;C-ii (d) A-i;B-iii;C-ii
Which of the following is a homopolysaccharide?
(d) Hyaluronic acid
From the following groups, select the one which has only secondary metabolites?
(a) Arbin, cellulose, arginine, tyrosine
(b) Glycine, gums, serine, diterpenes
(c) Carotenoids, phenylalanine, curcumin, rubber
(d) Conclavin-A, morphine, codeine, vinblastine