List of practice Questions

E.coli having $pBR322$ with $DNA$ insert at BamHI site cannot grow in medium containing tetracycline. Recognition site for BamHI is present in $tet^R$ region of $pBR322$.

Earthworms are known as 'friends of farmers' Earthworms make burrows in the soil and make the soil porous, which helps in respiration and penetration of developing plant roots

Diaphragms, cervical caps and vaults are barriers made of rubber. Diaphragms, cervical caps and vaults are inserted into the male reproductive tract during coitus.

Dark reactions are called biosynthetic phase of photosynthesis. Dark reactions do not directly depend on the presence of light but are dependent on the products of the light reaction, i.e., $ATP$ and $NADPH$.

Decomposition of hydrogen peroxide is an example of disproportionation reaction. In a disproportionation reaction, an element in one oxidation state is simultaneously oxidised and reduced.

Diamond is the hardest substance on the earth. It has high melting point.

Cresols are less acidic than phenol. Electron releasing groups do not favour the formation of phenoxide ion.

Crossing over leads to recombination of genetic material on the two chromosomes. : Crossing over is the exchange of genetic material between two homologous chromosomes.

$CsCl$ has body-centred cubic arrangement. $CsCl$ has one $Cs^+$ ion and $8\, Cl^-$ ions in its unit cell.

$Cr^{2+}$ is reducing and $Mn^{3+}$ is oxidising. $Cr^{2+}$ and $Mn^{3+}$ have $d^4$ configuration.

Copper dissolves in dilute nitric acid but not in dilute $HCl$. Copper has positive $E^?$.

Cork or phellem is impervious to water. Cork has suberin deposition in the cell wall.

Compressed natural gas $(CNG)$ is natural gas under pressure and mainly composed of methane. One of the advantages of using $CNG$ as a fuel in automobiles is that it requires very less space for storage as compared to that of petrol or diesel.

Connective tissues are the most abundant and widely distributed in the body of complex animals Connective tissues link and support other tissues or organs of the body

Consciousness is a defining property of living organisms. Human being is the only organism that has self consciousness.

Cooking food is difficult on hills. The boiling point decreases with increase in pressure.

CO and CN are referred as $\pi$ acid ligands. In CO and CN vacant $\pi$ type orbitals are present.

Cockroach shows sexual dimorphism The female cockroach bears a pair of short thread like anal styles

Cohesion, adhesion and surface tension give high tensile strength to water. Capillarity is aided by small diameter of the tracheary elements.

Common name of $1,1$-dichloroethane is ethylidene chloride. Ethylidene chloride is a gem-dihalide.

Classical smog is oxidising smog whereas photochemical smog is reducing smog. Classical smog occurs in warm, dry and sunny climate whereas photochemical smog occurs in cool humid climate.

Classification is necessary to study all living organisms. In classification, individuals are grouped into categories.

Closed circulatory system is less efficient than open circulatory system. The blood flow is slow in closed circulatory system than in open circulatory system.

$CO_{2}$ is a gas at room temperature while $SiO_{2}$ is a crystalline solid. $SiO_{2}$ is a network of silicon and oxygen atoms joined by multiple bonds.

Catenation tendency is weaker in nitrogen. Nitrogen exists as diatomic gas.