How are the alveoli designed to maximize the exchange of gases?
Answer: The human respiratory tract is made up of the nostril, larynx, nasal chamber, pharynx, trachea, epiglottis, alveoli, bronchioles, bronchi and... View Article
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The root mean square (R.M.S.) Speed V of the molecules of an ideal gas is given by the expressions, v = sqrt (3RT/M) and v = sqrt (3KT/m) where R is universal gas constant, T is the absolute (Kelvin) temperature M is the molar mass, K is Boltzman’s constant and M is the molecular mass. The R.M.S. speed of oxygen molecules (O2) at temperature T1 is V1. When the temperature is doubled, if the oxygen molecules are dissociated into atomic oxygen, what will be R.M.S. speed of oxygen atoms? (Treat the gas as ideal).
We have V1 = sqrt (3RT1/M) or V1 = sqrt (3kT1/m) on dissociation the molar mass as well as the... View Article
Select the incorrectly matched pair with regard to the C4 cycle. (1) Primary CO2 fixation product – PGA (2) Site of initial carboxylation – Mesophyll cells (3) Primary CO2 acceptor – PEP (4) C4 plant – Maize (5) Location of enzyme RuBisCO – Bundle sheath cells
Answer: (1) Primary CO2 fixation product – PGA The primary CO2 fixation product in C4 plants is oxaloacetic acid, which is... View Article
In PCl5, the three P- Cl bonds in plane are called as
For molecules adopting trigonal bipyramidal geometry there are 5 bonds. The three bonds in the plane called planar bonds or... View Article
Under what conditions is the work done i) maximum and ii) minimum?
Work done = FsCosθ Were θ is the angle between Force(F) and displacement(s). (i) Work done will be maximum when... View Article
Medicines that helps us to get rid of pain are called as:
Medicines that help us to get rid of pain are called as analgesics. Analgesics reduce or abolish pain without causing... View Article
An electric lamp of 100 Ohms, a toaster of resistance 50 Ohms, and a water filter of resistance 500 Ohms are connected in parallel to a 220 V source. What is the resistance of an electric iron connected to the same source that takes as much current as all three appliances, and what is the current through it?
Given parameters: Resistance of electric lamp (R1) = 100 Ω Resistance of toaster (R2) = 50 Ω Resistance of water... View Article
Kingdom Plantae has five divisions. Riccia and Funaria belongs to which category?
Riccia and Funaria are non-vascular plants which are found on land. They require water for survival and reproduction. They are... View Article
A stone of 1 kg is thrown with a velocity of 20 m s-1 across the frozen surface of a lake and comes to rest after travelling a distance of 50 m. What is the force of friction between the stone and the ice?
Given The initial velocity of the stone, u= 20 m/s The final velocity of the stone, v= 0 Distance covered... View Article
Name the blood vessel that has the lowest concentration of urea.
Urea is excreted out by the kidneys. Therefore, the blood vessel that leaves the kidneys will have the least concentration... View Article
Using a horizontal force of 200 N, we intend to move a wooden cabinet across a floor at a constant velocity. What is the friction force that will be exerted on the cabinet?
The cabinet will move with constant velocity only when the net force on it is zero. As the velocity of the... View Article
Answer the following questions on thermionic emission. a. Define Thermionic Emission. b. Mention an application of Thermionic Emission. c. Name a substance that is a good thermionic emitter.
a. The emission of electrons when heat energy is supplied to a metal surface is known as thermionic emission. b.... View Article
A man with blood group A marries a woman with blood group O and their daughter has blood group O. Is this information enough to tell you which of the traits blood group A or O is dominant? Why or why not?
Answer: The dominance of a trait is tested over at least 3 generations. In the above discussed situation, data from... View Article
Infants are vaccinated against many diseases. By vaccination their immune system gets
In the process of vaccination, infants immune system is activated so that in next invasion of the causative agent, the... View Article
Why does an ionic compound conduct electricity?
Answer: A solution of ionic compounds in water contains ions, which moves to the opposite electrodes when electricity is passed... View Article
Natural phenomenon like fog, mist or frost are caused due to (fill in the blank). a.Evaporation b.Transpiration c.Condensation d.Freezing
Fog, mist or frost are caused due to condensation. Condensation is a process when water is condensed or cooled to... View Article
In conversion from ethanol to ethene, concentrated sulphuric acid is used as:
During the conversion of ethanol into ethene in the presence of con. Sulphuric acid, a molecule of water is lost.... View Article
What is the ratio of C.G.S. to M.K.S. unit of acceleration?
C.G.S unit of acceleration = 1 cm/s2 M.K.S. unit of acceleration = 1m/s2 The ration of C.G.S. to M.K.S. unit... View Article
An insulated copper wire is wound on a soft iron core. Current is passed through the coil such that at end A the current flows anti- clockwise and a magnetic compass needle placed at other end B of the coil. a) What polarity is created at B? b) How is the magnetic compass affected when current flows through the coil?
Answer: i) At end B current flows clockwise thus end B becomes the South Pole. ii) The compass needle will... View Article
In an experiment, Radha took small amounts of an unknown food item in a test tube. Then, she added two drops of copper sulphate solution in the test tube along with a few drops of caustic soda solution. After a few minutes, the colour of the food item changed to violet.In the given experiment, the change in colour of the food item to violet indicates the presence of
The change in colour of the food item to violet after the addition of copper sulphate and caustic soda solution... View Article
