in the molecular orbital diagram of O₂ molecule, it may be noted that it contains two unpaired electrons in ∏^*2p_x and ∏^*2p_y molecular orbitals. When orbital is changes to O₂^- the next electron adds in the ∏^* orbitals.

generally the presence of electron withdrawing group (EWG) increases the acidic character of the carboxylic acids. Higher the number of halogen atoms increases the strength of acid. Hence, trichloroacetic acid has the highest acidity among the given compounds.

Flocculation refers to the process by which fine particulates are caused to clump together. KBr is least effective since bromine ion has least charge as compared to other flocculating ions.

some fungi which inhabit soil helps to combat diseases caused by soil borne fungi. Species of trichoderma like trichoderma lignorum and gliocladium fimbriatum are found in damp soils. They inhibit the growth of mycellium of pythium. They supress the fungi causing disease to seedlings and therefore helps in to increase the growth of crops.

the genetically modified crop plants having cry or Bt toxin genes do not require protection of insecticides as they themselves act as bio insecticides. Some common insects affected by Cry proteins are lepidoterans (tobacco budworm, armyworm), coleopterans (beetals), and dipterans (flies, mosquitoes).

Hybrid vigour also known as heterosis or outbreeding enhancement is the improved or increased function of any biological quality in a hybrid offspring. It is done in maize by cross breeding two different pure-bred lines having certain desirable traits.

Electron Spin Resonance (ESR) is a process which measures the number of charges occupying deep traps in crystal band gap. The basic principle of ESR is same as those for luminescence when electrons become trapped and are stored as a result of ionizing radiations for e.g., Dating of tooth enamel.

The events for initiation of DNA replication in prokaryotes may be given as follows 
(a) pre-priming (occurring only at the origin); 
(b) priming (recurring with the initiation of each okazaki fragment during elongation phase. 
Unwinding of DNA is followed by the synthesis of RNA primers by RNA primase.

Clotting of blood can be prevented by coating the test tubes with silicon or adding chelating agents.Heparin, citrate and EDTA are anti-coagulants.

In the resting state of neural membrane, the cytoplasm inside the axon has a high concentration of K⁺ and a low concentration of Na⁺thus if diffusion occurs against concentration gradient Na+ enters the cell.

Glomerular filtration depends on three main types of pressure. One pressure, the glomerular blood hydrostatic pressure, promotes the process of filtration. The other two pressures, the capsular hydrostatic pressure and the blood colloid osmotic pressure, that opposes filtration.

Gills are present in fishes and aquatic animals. They are used to remove carbondioxide in the aquatic animals. They also excrete salt in many bony fishes.