Questions

The kidneys are stimulated to produce renin by a decrease in the blood pressure.

The renin-angiotensin system or RAS regulates blood pressure and fluid balance in the body. When blood volume or sodium levels in the body are low, or blood potassium is high, cells in the kidney release the enzyme, renin. Renin's primary function is therefore to eventually cause an increase in blood pressure, leading to restoration of perfusion pressure in the kidneys.

The inherited traits of an organism are controlled by DNA molecules.

The traits an organism displays are ultimately determined by the genes it inherited from its parents, in other words by its genotype. Animals have two copies of all their chromosomes, one from each parent.

The sentence that states the main idea of the paragraph is called as Thesis or the topic sentence.

A : B = (800 × 8+ 900+ 1000+ 1100+ 1200): (1600 × 8+ 1700+ 1800+ 1900+ 2000)
A : B = 53 : 101
Profit of A ⇒ 7700 ×53/154 = 2650 Rs.

The order of basicity for primary, secondary and tertiary amines are:

Secondary > Primary > Tertiary > NH3

* Amines are basic in nature as they have lone pair of electrons on nitrogen. Therefore, they have a strong tendency to donate this lone pair of electrons to electron acceptors.

* The stability of conjugate acids formed is dependent on the extent of H-bonding,and greater the number of H-atoms on N more stable is the conjugate acid.

* The conjugate acid of primary amine is the most stable with greater number (3) of H-bonds than > Secondary > tertiary. But primary amines are less basic than secondary as the electron density on the N atom is less and lone pair of electrons are not readily available for protonation.

* The two opposing factors i.e. the stability of conjugate acids formed and ease of availability of electrons for Protonation, balance each other in case of secondary amines and it is most basic.