Biomolecules MCQ Questions & Answers in Organic Chemistry | Chemistry

The number of molecules of $$ATP$$  ( Adenosine tri phosphate ) produced in lipid metabolism of a molecule of palmitic acid is 130. Monosaccharide ribose is an $$ATP,$$  which acts as energy currency of the cells during metabolism of carbohyd rates, protein and fats.

Enzymes are globular proteins which catalyse biochemical reaction in the living systems.

Gene is a hereditary unit consisting of a sequence of $$DNA,$$  and occupying a specific position or locus within the genome.

Thytoxine is $$3,5,3',5' - $$  tetra iodothyronine. It is secreted by follicular cells of thyroid glands.
Its structure is given as

Thyroxine stimulates the consumption of oxygen and thus, the metabolism of all cells or tissues in the body.

$${C_6}{H_{12}}{O_6} + 6{O_2} + 2ATP \to 6C{O_2} + 6{H_2}O + 38\,ATP$$
∴ Net $$ATP$$  molecules evolved $$= 36$$

Molisch's Test : This is a general test for carbohydrates. One or two drops of alcoholic solution of $$\alpha $$ - naphthol is added to $$2 ml$$  glucose solution. $$1 ml$$  of cone. $${H_2}S{O_4}$$  solution is added carefully along the sides of the test tube. The formation of a violet ring at the junction of two liquids confirms the presence ofa carbohydrate or sugar.

Vitamin $${B_6}$$  is called pyridoxine. It is found in fruits, green-vegetables, milk, etc.

$$RNA$$  and $$DNA$$  molecules have ribose and deoxyribose sugar respectively. Both are chiral, their chirality is due to $$D$$ - ribose or deoxyribose sugar components.

Sucrose does not contain a free aldehydic or ketonic group hence it does not show mutarotation.

Cyclization of the open chain structure of $$D - \left( + \right) - $$  glucose has created a new stereocenter at $${C_1}$$ which explains the existence of two cyclic forms of $$D - \left( + \right) - $$   glucose, namely $$\alpha - $$ and $$\beta - .$$  These two cyclic forms are diasteromers, such diastereomers which differ only in the configuration of chiral carbon developed on hemiacetal formation ( it is $${C_1}$$ in glucose and $${C_2}$$ in fructose ) are called anomers and the hemiacetal carbon $$\left( {{C_1}\,{\text{or}}\,{C_2}} \right)$$  is called the anomeric carbon.