31 Year NEET Previous Year Questions: Biomolecules - 2 - NEET MCQ

Manufacture - By hydrolysis of starch with
hot dil. mineral acids

Structure of DNA - It consists of two
polynucleotide chains, each chain forms a
right handed helical spiral with ten bases in
one turn of the spiral. The two chains coil to
double helix and run in opposite direction
held together by hydrogen bonding.

Enzymes being biocatalyst can increase the
rate of a reaction upto 10 million times. Even
very small amount can accelerate a reaction.

Basically digestion means hydrolysis.

α -D glucose and β–D glucose are the
isomers which differ in the orientation
(configuration) of H and OH groups around
C₁ atom.

When antigens enter in to the body cells
and destroy them, then antibodies being
proteins are synthesised in the body and
combine with antigens and destroy these
antigens by forming inactive complexes.
Therefore antibodies protein destroy
antigens.

The correct answer is option  B
Calcium ions (Ca²⁺) contribute to the physiology and biochemistry of organisms' cells. They play an important role in signal transduction pathways, where they act as a second messenger, in neurotransmitter release from neurons, in contraction of all muscle cell types, and in fertilization.

The hydrolysis of sucrose by boiling with
mineral acid or by enzyme invertase or
sucrase produces a mixture of equal
molecules of D(+) glucose and
D(–) Fructose.

2, 4- Dinitroflurobenzene, also known as
Sanger's reagent, reacts with the H2N - group
of the peptide to from 2, 4- dinitrophenyl
(DNP) derivative of the peptide. The DNP
derivative of the peptide is hydrolysed to
give DNP derivative of the single amino acid

 Water oxidation is catalyzed by a manganese-containing cofactor contained in photosystem II known as the oxygen-evolving complex. Manganese is an important cofactor, and calcium and chloride are also required for the reaction to occur.

Peptide bonds are present in enzyme

We know that in the lipid metabolism, when
palmitic acid is oxidised, then two carbon
fragments are removed sequentially to form
acetyl coenzyme. It enters the citric acid
cycle for production of 130 ATP.

In DNA, adenine faces thymine and guanine
faces cytosine.

We know that glucose reacts with one
molecule of phenyl hydrazine to give phenyl
hydrazone. When warmed with excess of
phenylhydrazine, the secondary alcoholic
group adjacent to the aldehyde group is
oxidised by another molecule of
phenylhydrazine to a ketonic group. With this
ketonic group, the third molecule of
phenylhydrazine condenses to glucosazone.
Therefore the value of X is 3

Fructose is the sweetest sugar.

Net total number of ATP molecules evolved
= 36 molecules.

Progesterone (Gestogens) is a steroid
hormone, which controls the development
and maintainance of pregnancy. Thryoxine
and Adrenaline are Amine hormones.

Na⁺, Cl^– and HCO₃^– are the electrolytes
present in plasma solutes in blood. Na+ and
Cl^– helps in maintainence of osmotic
pressure and fluid balance.

There are 20 amino acid in man out of which
10 amino acids are essential amino acids.
These essential amino acids are supplied to
our bodies by food which we take because
they cannot be synthesised in the body
.These are (i) valine (2) leucine (3) Isoleucine
(4) Phenyl alanine (5) Threonine (6)
Methionine (7) Lysine (8) Tryptho phone (9)
Arginine (10) Histidine.

Chlorophyll contain Mg.

Glucose contain aldehyde group. Hence it
give positive fehling solution test.

Due to resonance C — N bond in protein
acquires double bond character and is
smaller than usual C — N bond.

Starch is also know as amylum which occurs
in all green plants. A molecule of starch
(C₆H₁₀O₅ )n is built of a large number of
α-glucose ring joined through oxygen-atom.

The hydrogen bonds are formed between
the base (shown by dotted lines). Because
of size and geometrics of the bases, the only
possible pairing in DNA and between
G(Guanine) and C(Cytosine) through three
H-bonds and between A (Adenosine) and T
(Thymine) through two H-bonds.