Which functional group participates in disulphide bond formation in proteins?
A
Thioester
B
Thioether
C
Thiol
D
Thiolactone
Explanation
Disulphide bond may be reduced to thiol
by means of reagents i.e., NaBH4
, which shows the
presence of thiol group in disulphide bond
formation.
2
AIPMT 2005
MCQ (Single Correct Answer)
The cell membranes are mainly composed of
A
fats
B
proteins
C
phospholipids
D
carbohydrates
Explanation
Cell membranes (Plasma membranes) constitutes bilayer of phospholipid with embedded
proteins. In humans, lipids accounts for upto
79% of cell membrance.
3
AIPMT 2004
MCQ (Single Correct Answer)
Which of the following structures represents the peptide chain?
A
B
C
D
Explanation
In peptide linkage i.e., (– CONH) group,
the carboxyl group of one amino acid molecule forms
an amide by combination with the amino group of
the next amino acid molecule with the liberation of
water molecule.
4
AIPMT 2004
MCQ (Single Correct Answer)
The helical structure of protein is stablised by
A
dipeptide bonds
B
hydrogen bonds
C
ether bonds
D
peptide bonds
Explanation
The $$\alpha $$-helix structure is formed when the
chain of $$\alpha $$-amino acids coils as a right handed
screw (called $$\alpha $$-helix) because of the formation
of hydrogen bonds between amide groups of
the same peptide chain, i.e., NH group in one
unit is linked to carbonyl oxygen of the third
unit by hydrogen bonding. This hydrogen
bonding between different units is responsible
for holding helix in a position.
Questions Asked from Biomolecules
On those following papers in MCQ (Single Correct Answer)
Number in Brackets after Paper Indicates No. of Questions
