Immunology MCQ for NET Life Science Exam with Answer Key (MCQ 001)


Immunology Quizzes

Immunology MCQ-01
(Biology / Life Sciences MCQ: Multiple Choice Questions in Immunology)

Immunology MCQ for CSIR NET Life Science Exam, Dec – 2017
(Sample/Model/Practice Questions for CSIR JRF/NET Life Science Examination, ICMR JRF Exam, DBT BET JRF Exam, GATE BT and XL Exam, ICAR JRF NE Exam, PG Entrance Exam, JAM Exam, GS Biology Exam and Medical Entrance Exam)

(1).  The stimulation of antigen specific T cells by appropriately presented antigen alone results in _____

a.       Cytotoxicity
b.      Allergy
c.       Cell division
d.      Production of IL-3

(2).  The thymus independent type I antigens are ______

a.       Polysaccharide of bacterial origin
b.      Small proteins of bacterial origin
c.       Bacterial nucleic acids
d.      Viral nucleic acids

(3).  Which of the following statement is true about Th-1 cells?

a.       They do not produce TNFγ
b.      They do not express CD4
c.       They don not binds to soluble proteins
d.      They don not activate macrophages

(4).  Select the false statement about T cells.

a.       T cells do not produce the IL-2
b.      T cells will not respond to IL-4
c.       T cells will not respond to IL-2
d.      T cell mediate their functions only through cell to cell contact

(5).  Which among the following can inhibit inflammation?

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Difference between Type I and Type II Interferons (INF Alpha/Beta vs INF Gamma)


Difference between INF alpha beta and gamma

Type I Interferons vs Type II Interferons
(Similarities and Differences between Type I and Type II Interferons)

Interferons or INFs are glycoproteins with indirect antiviral properties. They are cytokines whose production in the cell is induced by viral infections. Interferons stimulate the synthesis of antiviral proteins in the cells which inhibit the multiplication of viral particles.  

Learn more: Interferons: Definition, Properties, Antiviral Properties and Clinical Uses

Interferons are classified into TWO categories based on their type of Receptors. They are Type I Interferons (INFα and INFβ) and Type II Interferons (INFγ). The present post describes the Similarities and Differences between Type I and Type II interferons.

Similarities between Type I and Type II Interferons

Ø  Both type I and type II interferons are short glyco-proteins.

Ø  Both possess indirect antiviral properties.

Ø  The production of both types of interferons is triggered by viral infections.

Ø  Both can elicit immunological responses in the organ.

Ø  Both types operate through receptors present on the plasma membrane.

Ø  Both can trigger the production of antiviral proteins.

Difference between Type I and Type II Interferons

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Interferons (INF): Definition, Antiviral Properties, Functions, Classification and Clinical Significance


Functions Interferon

INTERFERONS
(INF: Definition, Antiviral Properties, Classification and Clinical Significance)

Interferons are Glycoproteins with Antiviral Properties

Interferons or INFs are low molecular weight glyco-proteins produced by certain eukaryotic cells in response to viral infections. They are cytokines with indirect or non-specific antiviral activities. Interferons stimulate the production of antiviral proteins in the cells which inhibit the synthesis of viral RNA and proteins. Interferons cannot directly inhibit the viral entry into the host cell. However, they can inhibit the replication of viral gene and the assembly of viral particles and thereby they limit the viral infection.

Interferons also regulate the growth, differentiation and functions of different types of immune cells in animals. Several classes of interferons are recognized in eukaryotes such as INFα, INFβ and INFγ. INFα and INFβ are produced by virus infected fibroblasts. Virus infected leukocytes, antigen stimulated T cells and natural killer cells can produce INFγ.

Interferon Production is Triggered by Viral Infection

The synthesis and release of interferons form a cell is induced by the viral particles. The intact viral particles and even the presence of double stranded viral RNA (dsRNA) in the cell can evoke the production of interferons. Specific interferons are recognized by receptors present on the plasma membrane. Once a cell receives the stimuli, the interferon proteins are synthesized and they are released out of the cell. Since they are secreted to the exterior of the cells, they can bind to its plasma membrane receptors. The secreted interferon molecules then bound to the ganglioside receptors on the plasma membrane of another cell (nearby or located far away from the secretion).

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Biotechnology Lecture Notes

Solid State Fermentation Technology: Examples, Advantages and Disadvantages


Solid-Substrate-Fermentation-SSF

Solid State Fermentation (SSF)
(Solid State Fermentation: Technology, Advantages and Disadvantages)

What is Solid State Fermentation (SSF)?

In Solid State Fermentation, also called Solid Substrate Fermentation or SSF, the fermentation substrate or media will be in the solid state. Here the microorganisms are grown on a solid substratum in the absence or near absence of free water. The moisture content of the substratum in SSF is usually maintained below 15%. The solid state fermentation is most commonly carried out for the production of fermented food products such as bread, fermented fish, meat, yogurt, cheese and pickles. The microbial fermentation increases the nutrient content and flavor of food products. It also increases the digestibility of foods. The cultivation of edible mushrooms on a suitable substratum is also a solid state fermentation process.

Pleurotus djamor

Mushroom Cultivation (wikipedia)

Substrates / Media in Solid State Fermentation

 

The substrates commonly used in SSF are usually very complex, heterogeneous and are insoluble in water. These substrates include cereals grains, wheat bran, lingo-cellulosic materials such as wood shavings, sawdust, molasses etc. In most of the cases, the substrate or the raw materials were undergone through a pre-treatment such as soaking, boiling in water, mechanical pre-treatment or chemical treatment. These pre-treatments increase the bioavailability of nutrients for the microbes to act on them.

Instrumentation and Growth Kinetics in Solid State Fermentation

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Molecular Biology Tutorials

Philadelphia Chromosome and Oncogenic BCR ABL Gene Translocation in CML


Philadelphia Translocation

Philadelphia Chromosome (PH)
(Philadelphia Translocation, PH and Chronic Myeloid Leukemia – CML)

Translocation is a Structural Aberration of Chromosome

Translocation is a type of structural aberration of the chromosome where a segment of chromosome gets translocated to another chromosome. There may be two types of translocation based on the nature of the exchange. They are:

(1). Homologous Translocation

(2). Heterologous Translocation

In homologous translocation, the exchange of chromosomal segments occurs between the homologous chromosomes. In heterologous translocation, the chromosomal segments are exchanged between non-homologous chromosomes. The heterologous translocation in most of the cases will be a reciprocal translocation (exchange of segments between chromosomes).

Translocation causes ‘Position Effect’

The translocation of chromosomes leads to a phenomenon in molecular genetics called the ‘Position Effect’. The position effect is the change in the expression pattern of a gene due to its current position in the chromosome. For example, a normally active gene may be converted to an inactive gene when it is translocated into a new position or vice versa.

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