Compare the following :
(a) Central nerual system (CNS) and Peripheral neural system (PNS).
(b) Resting potential and actions potential .
(c ) Choroid and retina.

Which of the following statemente is / are INCORRECT? (a) Mechanical energy is the sum of kinetic energy and potential energy. (b) Potential energy is a relative quantity. It depends on the choice of reference point. (c ) Kinetic energy must be non negative. (d) Potential energy must be postive.

Answer the following : (a) Which part of the ear determines the pitch of a sound ? (b) Which part of the human brain is the most developed ? (c ) Which part of our central neural system acts as a master clock ?

Differentiate between the following: (a) Diffusion and Osmosis (b) Transpiration and Evaporation (c) Osmotic Pressure and Osmotic Potential (d) Imbibition and Diffusion (e) Apoplast and Symplast pathways of movement of water in plants. (f) Guttation and Transpiration.

Two cylinders A and B of equal capacity are connected to each other via a stopcock. A contains a gas at standard temperature and pressure. B is completely evacuated. The entire system is thermally insulated. The stopcock is suddenly opened. Answer the following: (a) What is the final pressure of the gas in A and B ? (b) What is the change in internal energy of the gas ? (c) What is the change in the temperature of the gas ? (d) Do the intermediate states of the system (before settling to the final equilibrium state) lie on its P-V-T surface ?

In a hydrogen atom, the electron and proton are bound at a distance of about 0.53 Å (a) Estimate the potential energy of the system in eV, taking the zero of the potential energy at infinite separation of the electron from proton. (b) What is the minimum work required to free the electron, given that its kinetic energy in the orbit is half the magnitude of potential energy obtained in (a)? (c) What are the answers to (a) and (b) above if the zero of potential energy is taken at 1.06 Å separation?