CSIR JRF NET Life Sciences December 2017 Solved Question Paper PDF
Official / Original Previous Year (Old) Solved Question Paper of CSIR Junior Research Fellowship (JRF) and National Eligibility Test (NET) Life Sciences (XL) Examination December 2017 with Answer Key as PDF. CSIR aspirants can download the question paper as single PDF file for your exam preparation. To download the question paper, please click on the download link below the PDF preview. Please inform the Adminif you find any mistake in the answer key.
Gibberellic Acid (GA) vs Abscisic Acid (ABA) (Difference between the Physiological Effects of Gibberellic acid and Abscisic Acid in Plants)
Gibberellin (Gibberellic Acid) and Abscisic Acid (ABA) are two important plant hormones. Plant Hormones also called ‘Phytohormones’ or ‘Plant Growth Substances’, are signaling molecules produced in very minute quantities in the plants that have immense physiological and metabolic effects. They regulate the growth and development of plants.
The present post discusses the Difference between the Physiological effects of Gibberellin (Gibberellic Acid) and Abscisic Acid (ABA) in plants with a Comparison Table.
Gibberellic Acid: Gibberellic acid or gibberellin, abbreviated as GA, is a major phytohormone produced by some plants and microbes (fungi) which promote the growth and cell elongation. Gibberellic acid was first identified in Japan as a metabolic by-product of a plant pathogenic fungus called Gibberella fujikuroi. The infection of rice plants with this fungi cause a disease called ‘bakane’ meaning ‘foolish seedlings’. The diseased plants will grow much taller than the normal and they eventually die because they are not sturdy enough to support their own weight. The excessive elongation of the internodes in these infected plants was found be to be due to the effect of Gibberellic acid produced by the pathogen.
Structure and Functions of Immunoglobulins (Antibodies) The Organization of Heavy and Light Chains in an Immunoglobulin (Ig)
In the previous post, we have discussed the introductory features of antibodies. There we have also discussed the reason for calling Antibodies (Ab) as Immunoglobulins (Ig). In this lesson, we will see the detailed molecular structure and organization of immunoglobulins (antibodies).
What are Immunoglobulins (Ig)?
As we discussed earlier, the Antibodies or Immunoglobulins are globularproteinspresent in the serum and tissue fluids. They are produced by the plasma cells (B-cells) and are used in theimmune systemof the body to neutralize pathogenic microbes or other toxic foreign components. Antibodies play a very crucial role in the immune system of an organism. Antibodies bind to definite molecules of microbes called antigens with high affinity and specificity. This enables our immune system to detect foreign organisms such as invading pathogens, of its products and initiate the mechanism to eliminate these foreign particles. The production of antibodies by the plasma cells is also stimulated by the antigens.
How Immunoglobulins (Ig) are classified?
The immunoglobulins constitute about 20 – 25% of the total serum proteins. Based on the Physiochemical and Antigenic differences, the immunoglobulins are classified into FIVE categories. These immunoglobulins variants are called as Isotypes. The five isotypes or classes of the immunoglobulins are given below.
Flower vs Vegetative Branch (Difference between Flower and Reproductive Shoot)
The flower is the reproductive structure formed in the plant group Angiosperms or Magnoliophyta, commonly called as the ‘Flowering Plants’. The flower is a ‘modified branch’ or axis developed from a ‘determinate’ apical meristem. The term ‘determinate’ indicates the absence of further growth of the apical meristem after the production of flowers. Even though the flower is a modified shoot, the morphological and anatomical features of a flower and a vegetative branch show many differences. The present post discusses the Difference between a Flower and a Vegetative Branch with a Comparison Table.
Lyophilic Sols vs Lyophobic Sols (Difference between Lyophobic and Lyophilic Sols)
Sols are colloidal systems in which a solid is dispersed in a liquid. There are two types of sols – (1) Lyophobic Sols and (2). Lyophilic Sols
(1). Lyophilic sols: They are solvent loving sols. In lyophilic sols, the dispersed phase shows a positive affinity for the dispersion medium (solvent). The high affinity of dispersed particles with the dispersed medium is due to the formation of a large number of hydrogen bonds.
(2). Lyophobic sols: They are solvent hating sols. In lyophobic sols, the dispersed phase does not have any attraction for the dispersion medium.