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Right choice is (C) SERINE

To explain I would say: LYSINE and ARGININE are polar and POSITIVELY charged amino acids. While Aspartate is a polar and negatively charged amino acid. Serine is a polar and uncharged amino acid.

Right option is (a) Protein folding occurs in Golgi bodies

The explanation: The folding of proteins occurs in the lumen of the ENDOPLASMIC RETICULUM (ER). A NEWLY synthesized protein undergoes a series of modifications in the ER with the help of a number of MOLECULAR chaperones and folding enzymes that all together assist its PROPER folding and subsequent release from ER. The majority of ER proteins are dedicated to the folding of proteins. Golgi bodies help in the proper packaging and transport of proteins.

Right OPTION is (c) Histidine

To EXPLAIN: The amino acids may be negatively CHARGED, positively charged or neutral at a neutral pH. Here, Arginine and Lysine are positively charged or protonated at neutral pH, while Glutamate is negatively charged at neutral pH. However, Histidine may or may not be protonated at normal pH. The side chain of Histidine has a pKa of 6.5, which MEANS only 10% of Histidine is protonated.

Correct option is (d) snRNA

Easy explanation: micro RNA(miRNA) is a SMALL non-coding RNA that helps in gene silencing. Small interfering RNA (siRNA) helps in gene silencing through the RNA interference pathway. Short HAIRPIN RNA (shRNA) SILENCES TARGET gene via RNA interference. However, small NUCLEAR RNA or snRNA helps in RNA splicing and processing.

The correct choice is (d) GLYCOSAMINOGLYCAN

For EXPLANATION: A more complex STRUCTURES of polysaccharides is glycosaminoglycan (GAGs). Unlike other polysaccharides, they have an A-B-A-B where A and B represent two different sugars.An EXAMPLE of GAG is heparin, which is secreted by cells in lungs against tissue damage. Heparin prevents blood coagulation, enabling free FLOW of blood to heart or lungs.

The correct option is (d) ACETIC acid

To explain I would SAY: Sodium dodecyl sulfate or SDS is a strong denaturant of protein and is used in SDS-PAGE technique. DTT is OFTENTIMES used along with SDS to further denature proteins by reducing their disulfide bonds to ALLOW for better separation of proteins during electrophoresis. Phenol is used as a protein denaturant during isolation of RNA from plants.

The correct answer is (d) X-ray crystallography

Easy explanation: In X-ray crystallography technique, a crystal of the protein is bombarded by a thin beam of X-ray and the radiation that is scattered by the electrons of the protein’s atoms is allowed to strike a radiation sensitive plate or detector, forming an image of SPOTS. When these diffraction patterns are subjected to COMPLEX mathematical ANALYSIS, an investigator can work backward to derive the STRUCTURE responsible for producing the PATTERN.

The correct choice is (d) Disulphide bond

The best I can explain: Disulphide bond is not present in a DNA MOLECULE. PHOSPHATE bond is present between two deoxy-nucleotides (dNTPs) of DNA. The nitrogen bases on the two strands of DNA have hydrogen bonds between them. ADENINE is connected THYMINE by 2 hydrogen bonds, GUANINE is bound to Cytosine by 3 hydrogen bonds. The base stacking in DNA is due to Vanderwaal’s force.

The correct option is (c) Lactose and Cellobiose

To EXPLAIN: Among the disaccharides, sucrose, maltose and isomaltose have ALPHA(1->4) GLYCOSIDIC bond. However, lactose, lactulose and sucrose have beta(1->4) glycosidic LINKAGE.

Right choice is (b) Covalent > Ionic > Vanderwaal > HYDROGEN

The explanation: Intramolecular bonds are called covalent bonds and are far stronger that intermolecular forces (or bonds). The latter are usually ranked as follows: ionic > Vanderwaal > hydrogen. Hydrogen bonding includes inter MOLECULAR interactions with permanent dipoles (and partial charges) between hydrogen atoms and a few other elements. Vander WAALS interactions are based on random and instantaneous dipoles which last for fractions of a SECOND in long, polarizable bonds.

Right OPTION is (C) Exons

Easy EXPLANATION: Intervening sequences, also called introns are the portions of DNA excluded during transcription and thus are not there in the mRNA product. Exons are the part of DNA transcribed to form mRNA. The genes with intervening sequences are called SPLIT genes.

Correct OPTION is (c) STEROIDS are found in the cell membranes of both PLANT and animal

Easiest explanation: Cholesterol is a STEROID which is found in the cell membranes of animals. Cholesterol is largely absent from plant cells, which is why vegetable oils are considered “cholesterol-free”.

Right option is (c) Ethylene

Easiest explanation: Polar molecules occur when two atoms do not share ELECTRONS equally in a covalent bond. A dipole is formed, with part of the molecule CARRYING a slight POSITIVE charge and the other part carrying a slight negative charge. This happens when there is a difference between the electronegativity of each atom. An extreme difference forms an ionic bond, while a lesser difference forms a polar covalent bond. When molecules share electrons equally in a covalent bond there is no NET electrical charge ACROSS the molecule. In a nonpolar covalent bond, the electrons are evenly distributed.

Correct choice is (b) scRNA

Best explanation: siRNA, SNRNA and miRNA are all PRODUCED naturally in the cell. Small cytoplasmic RNA (scRNA) is an ENGINEERED (artificial) RNA MOLECULE that HELPS in in-vitro and in-vivo signal transduction.