mcq biology

NET Life Science Model Question Paper 2015: Biology MCQ-8: Biochemistry: Amino Acids: Part 4


Biology MCQ (Multiple Choice Questions in Life Science)
(Sample/Model/Practice Questions for JRF/NET Life Science Examination, ICMR JRF, DBT JRF, GATE, ICAR NET, PG Entrance)

MCQ Biochemistry: Amino Acids Part 4 (MCQ 008)


1). Which group of a fully protonated glycine (NH3+ – CH2 – COOH) first release a ‘proton’ when it is titrated against – OH- ions?

a.       Carboxyl group
b.      Amino group
c.       Both at the same time
d.      It cannot be predicted

2). pKa is the measure of a group to __________ proton.

a.       Take up
b.      Release
c.       Combine
d.      Consume

3). Which of the following amino acid bears a guanidine group in the side chain?

a.       Lysine
b.      Arginine
c.       Histidine
d.      Proline

4). The precursor of glycine synthesis in microbes and plants is_______.

a.       Serine
b.      Leucine
c.       Valine
d.      None of these

5). Single letter code of selenocysteine is _____.

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mcq biology

MCQ Biology 07: Biochemistry: Amino Acids – Part 3 for Life Science JRF/NET Examination, June 2015

Biology MCQ (Multiple Choice Questions in Life Science)
(Sample/Model/Practice Questions for JRF/NET Life Science Examination, ICMR JRF, DBT JRF, GATE, ICAR NET, PG Entrance)


Biochemistry: Amino Acids Part 3 (MCQ 007)


(1). pH below pI amino acids will be___.        (ICMR JRF Exam, 2006)

a.       Anionic
b.      Cationic
c.       Net charge zero
d.      No charge

(2). Naturally occurring proteins are usually polymers of _____.

a.       D-amino acids
b.      L-amino acids
c.       A mixture of D and L amino acids
d.      Either D amino acids or L- amino acids

(3). At zwitterionic form, an amino acid will act as_____.

a.       Proton donor
b.      Proton acceptor
c.       Proton donor and acceptor
d.      None of these

(4). Which of the following amino acid is more likely to occupy the interior of a globular protein?

a.       Methionine
b.      Aspartate
c.       Lysine
d.      Arginine
e.       All of these

(5). Proteins absorb UV light at 280 nm and show a characteristic peak at this wavelength. Which amino acid residue in the protein is responsible for this absorption?

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mcq biology

Biology MCQ-06: Biochemistry: Amino Acids: Part 2 for JRF/NET Life Science Examination


Biology MCQ With Answers and Explanations 
(Sample/Model/Practice Questions for JRF/NET Life Science Examination, ICMR JRF, DBT JRF, GATE, ICAR NET, PG Entrance)

Biology MCQ-6: Biology/Life Science Multiple Choice Questions (MCQ) / Model Questions with answers and explanations in Biochemistry: Amino Acids Part 2 for preparing CSIR JRF NET Life Science Examination and also for other competitive examinations in Life Science / Biological Science such as ICMR JRF Entrance, DBT JRF, GATE Life Science, GATE Biotechnology, ICAR, University PG Entrance Exam, JAM, GRE, Medical Entrance Examination etc. This set of practice questions for JRF/NET Life Science will help to build your confidence to face the real examination. A large quantum of questions in our practice MCQ is taken from previous year NET life science question papers. Please take advantage of our NET Lecture Notes, PPTs, Previous Year Questions and Mock Tests for you preparation. You can download these NET study material for free from our SLIDESHARE account (link given below).


Biochemistry MCQ: Amino Acids – Part 2 (MCQ-6)


.(1). Which amino acid, among the 20 standard protein coding amino acids, is most abundantly occurs in proteins?

a.       Glycine
b.      Methionine
c.       Serine
d.      Leucine

(2). Which of the following amino acid is having more polarity?

a.       Lysine
b.      Arginine
c.       Histidine
d.      Aspartate

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mcq biology

Biology MCQ-05: Biochemistry: Amino Acids: Part 1 for JRF/NET Life Science Examination


Biology MCQ with Answers and Explanations
(Sample/Model/Practice Questions for JRF/NET Life Science Examination, ICMR JRF, DBT JRF, GATE, ICAR NET, PG Entrance)

Biology MCQ-6: Biology/Life Science Multiple Choice Questions (MCQ) / Model Questions with answers and explanations in Biochemistry: Amino Acids Part 2 for preparing CSIR JRF NET Life Science Examination and also for other competitive examinations in Life Science / Biological Science such as ICMR JRF Entrance, DBT JRF, GATE Life Science, GATE Biotechnology, ICAR, University PG Entrance Exam, JAM, GRE, Medical Entrance Examination etc. This set of practice questions for JRF/NET Life Science will help to build your confidence to face the real examination. A large quantum of questions in our practice MCQ is taken from previous year NET life science question papers. Please take advantage of our NET Lecture Notes, PPTs, Previous Year Questions and Mock Tests for you preparation. You can download these NET study material for free from our SLIDESHARE account (link given below).


Biochemistry: Amino Acids Part 1 (MCQ 5)


.(1). Which of the following amino acid is sweet in taste?

a.       Glycine
b.      Alanine
c.       Glutamic acid
d.      None of these

(2). Which of the following amino acid act as inhibitory neurotransmitter?

a.       Glycine
b.      Alanine
c.       GABA
d.      All of these
e.       None of these

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biological chemistry

Enzyme Specificity (Biochemistry Lecture Notes)


Biochemistry of Enzyme Substrate Specificity and its Classification With Examples

.“There is more to life than increasing its speed…”

                                                                                    Mahatma Gandhi


Enzymes are biological catalysts. They accelerate the rate of metabolic reactions in the cells by reducing the activation energy of the reactants. Almost all enzymes are specialized proteins with definite structural conformations.

Important characteristic features of enzyme are:

1. Catalytic Power (ratio of enzyme catalyzed rate of a reaction to the un-catalyzed rate)

2. Regulation (control of enzymatic reaction)

3. Specificity (Selectivity of enzyme to their substrate)

What is enzyme specificity?

Specificity is the ability of an enzyme to choose exact substrate from a group of similar chemical molecules. The specificity is actually a molecular recognition mechanism and it operates through the structural and conformational complementarity between enzyme and substrate. Enzymes show different degrees of specificity towards their substrate.

how enzyme and substrate binds .. conformational asymmetry of enzyme and substrate

The specificity shown by enzymes are grouped into 6 categories

1.  Bond specificity

2.  Group specificity

3.  Substrate specificity

4.  Stereo specificity (Optical specificity)

5.  Geometrical specificity

6.  Co-factor specificity

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