Zoology MCQs for NEET — Practice Questions with Answers

Azidothymidine, also known as Zidovudine or AZT, is an antiretroviral medication used for the treatment of HIV/AIDS. It was one of the first drugs approved for the treatment of HIV/AIDS, and it remains an important component of many antiretroviral therapy regimens.

(d) H⁺ from weak acids or strong acids or enzyme's invertase catalyse the hydrolysis of sugar.

(b)

Radon decays into radioactive polonium and alpha particles. This emitted radiation made radon useful in cancer therapy.

(d) Phospholipids are esters of glycerol with two carboxylic acid residue and one phosphate group. Hence, phospholipids may be regarded as derivative of glycerol in which two hydroxyl groups are esterified with fatty acid, while third is esterified with phosphoric acid.

 Glucose reduces Fehling solution to give red ppt. of Cu₂O.

$\underset{Glu\cos e}{\underset{CHO}{\overset{CHO}{\underset{\left|}{\overset{\right|}{{\left(\mathrm{CHOH}\right)}_4}}}}}+\underset{Fehling solution}{2CuO}\to \underset{C{H}_{\mathit{2}}OH}{\overset{COOH}{\underset{\left|}{\overset{\right|}{{\left(\mathrm{CHOH}\right)}_4}}}}+\underset{\mathrm{Red} \mathrm{ppt}}{{\mathrm{Cu}}_2\mathrm{O}}$

 Fructose is the sweetest sugar and highly soluble in water and slightly soluble in alcohol and insoluble in ether fructose in laevorotatory hence, called laevulose.

(a) In DNA the two strands are held together by hydrogen bonds. For example guanine is bonded to cytosine and adenine to thymine by hydrogen bonding.

(c) The segment of DNA which acts as the instrumental manual for the synthesis of protein is gene. Every protein in a cell has a corresponding gene

 Starch is hydrolysed with dilute acids or enzymes and break down to molecules of variable complexity and finally gives D-glucose.

$$\begin{gathered} {\left({\mathrm{C}}_6{\mathrm{H}}_{10}{\mathrm{O}}_5\right)}_n \stackrel{ }{\to }{\left({\mathrm{C}}_6{\mathrm{H}}_{10}{\mathrm{O}}_5\right)}_{n\text{'}} \stackrel{ }{\to }{\mathrm{C}}_{12}{\mathrm{H}}_{22}{\mathrm{O}}_{11}\stackrel{ }{\to }{\mathrm{C}}_6{\mathrm{H}}_{12}{\mathrm{O}}_6 \\ \mathrm{Starch} \mathrm{Diastase} \mathrm{Maltose} \mathrm{D}-\mathrm{glucose} \end{gathered}$$