Why does the exchange of gases happen only in alveoli, though arteries are present in pharynx, trachea and bronchus?

The exchange of gases in the alveoli of the lungs takes place by

In which organisms does exchange of gases take place through diffusion ?

Why does the wooden block float on water even though it is heavier than a marble ?

Observe the diagram and answer the following. If only stamens are present in flower what does it indictes.

An atom is electrically neutral. But the electrons present in it are negatively charged particles. If only negative charges were present, the atom would not be neutral. Then, why are atoms considered to be neutral?

On the basis of the postulates of kinetic theory of gases, it is possible to derive the mathematical expression, commonly known as kinetic gas equation. PV = 1/3 m n u^3? where, P= Pressure of the gas, V a volume of the gas, m=Mass of a molecule, n = Number of molecules present in the given amount of a gas and u = root mean square speed For one mole of gas, PV = RT and n=N_A 1/3 m N_a u^2 = RT or 2/3 .1/2m N_A u^2 = N_A [1/2mN_Au^2 = KE "per mole"] ,2/3K.E. = RT implies K.E. 3/2RT Average kinetic energy per mol does not depend on the nature of the gas but depends only on temperature. This, when two gases are mixed at the same temperature, there will be no rise or decrease in temperature unless both react chemically. Average kinetic energy per molecule = ("Average K.E. per mole")/N = 3/2(RT)/(N) implies 3/2kT where k is the Boltzmann constant The average kinetic energy (in joule) of the molecules in 8g methane at 27&@C is.

On the basis of the postulates of kinetic theory of gases, it is possible to derive the mathematical expression, commonly known as kinetic gas equation. PV = 1/3 m n u^3? where, P= Pressure of the gas, V a volume of the gas, m=Mass of a molecule, n = Number of molecules present in the given amount of a gas and u = root mean square speed For one mole of gas, PV = RT and n=N_A 1/3 m N_a u^2 = RT or 2/3 .1/2m N_A u^2 = N_A [1/2mN_Au^2 = KE "per mole"] ,2/3K.E. = RT implies K.E. 3/2RT Average kinetic energy per mol does not depend on the nature of the gas but depends only on temperature. This, when two gases are mixed at the same temperature, there will be no rise or decrease in temperature unless both react chemically. Average kinetic energy per molecule = ("Average K.E. per mole")/N = 3/2(RT)/(N) implies 3/2kT where k is the Boltzmann constant Which of the following expressions correctly represents the relationship between the average molar kinetic energies of CO and N_2 molecules at the same temperature ?

Which of the following group constitute the right pathway of gases in the respiratory system ? A. Nostrils to Nasal cavity to Larynx to Pharynx to Bronchus to Trachea to Bronchioles to Alveolus to Blood B.Nostrils to Nasal cavity to Pharynx to Larynx to Trachea to Bronchus to Bronchioles to Alveolus to Blood

Why does the zygote begin to divide only after the division of Primary endosperm cell (PEC)?