Daily NEET MCQ- June 20, 2022 - NEET MCQ

The elements of carbon family exhibit + 2 and + 4 oxidation state. The compounds of plumbum in + 4 oxidation state are powerful oxidizing agents since +2 oxidation state of plumbum is more stable due to inert pair effect.

The Carbon family can form two types of oxides, mono oxides of the type MO like carbon monoxide and silicon monoxide which are all basic, it can also found the oxides of the type MO₂ where carbon dioxide and silicon dioxide are acidic and the dioxide of Germanium, silicon and plumber are amphoteric.

Carbon dioxide is linear gas at ordinary temperature but at low temperatures, it is in solid form and also known as dry ice or drikold. it is used for storing frozen substances at a lower temperature than normal water and it is used for cooling.

Let the pressure outside the bubble be P₁, between the two layers be P₂ and pressure inside the bubble be P₃.
P₂ – P₁ = 2S/R
P₃ – P₂ = 2S/R
∴ P₃ – P₁ = 4S/R
This shows that excess pressure just inside the first layer is 2S/R while excess pressure completely inside the bubble is 4S/R.

The pressure in the bubble will be more than the pressure just outside it by an amount 2S/R.
The pressure just outside the bubble is P₀ + ρgh.
Therefore, pressure inside bubble = P₀ + ρgh + 2S/R
= 10⁵ + (1000*10*1) + (2*0.075/0.01)
= 110015 Pa.

Rice doesn’t show vernalisation. Other crops such as Wheat, Barley and rye which are have two varieties: spring and winter require cold treatment to stimulate photoperiodic response of plants.

Polycarpic plants are plants that set seeds numerous times before senescence. Apple is a polycarpic plant. Sugarbeet, Cabbage & Carrots are some of the common biennials. Biennials are plants that take 2 seasons to complete their lifecycle.

Leaves are the site for perception of light/dark duration. Florigen is responsible for flowering. Shoot apices are modified to flowering apices prior to flowering. The hormone further migrates to stem and roots.

The hypothetical hormone florigen is said to be responsible for flowering in plants. Vernalin is promotes early maturity leading to flowering. ABA is majorly an inhibitor and functions in stressful conditions. Cytokinin stimulates shoots development.

Planaria uses the method of fragmentation and regeneration to reproduce. Whereas fungi reproduce using spores, amoeba uses binary fission to reproduce and hydra uses budding to reproduce.