Q 1. What are the main functional regions of a cell? Explain with the help of diagram.
Q 2. Assertion (A) : Plasma membrane is a selectively permeable membrane.
Reason (R) : Plasma membrane allows entry and exit of substance from cell through the process of diffusion.
(a) Both A and R are true and R is the correct explanation of the assertion.
(b) Both A and R are true but R is not the correct explanation of the assertion.
(c) A is true but R is false.
(d) Both A and R are false.
Q 3. Explain in details the structure of nucleus with the help of a diagram.
Q 4. Why is mitochondria called ‘powerhouse of cell’? Give three similarities and one difference between mitochondria and plastid.
or
Correlate the structure and location with the function in case of:
(a) Simple squamous epithelium
(b) Columnar epithelium
Q 5. Cell wall is mainly composed of
(a) Glucose
(b) Fructose
(c) Sucrose
(d) Cellulose
Q 6. A body starts from rest and moves with a uniform acceleration of 2 m s / 2- until it travels a distance of 625 m. Find its velocity.
Q 7. A car travels at 54 km/h for first 20s, 36 km/h for next 30 s and finally 18 km/h for next 10 s. Find its average speed..
Q 8. (a) A stone is allowed to fall from a tower of height 200 m and at the same time another stone is projected vertically upwards from the ground at a velocity of 20 m/s. Calculate when and where the stones will meet.
(b) The walls of your classroom are in motion butappear stationary. Explain.
Q 9. A. truck starts from rest and rolls down the hill with constant acceleration. It travels a distance of 500 m in 25 seconds. Find the force acting on it if its mass is 6 metric tons.
Q 10. Assertion (A) : In solids, molecules are tightly packed.
Reason (R) : Force of attraction between molecules in solids is very weak
Q 11. “Evaporation is a surface phenomenon.” Explain.
Q 12. The smell of hot sizzling food reaches you several meters away, but to smell the cold food you have to go close. Why?
Q 13. Comment on the following statements:
(a) Rate of evaporation of an aqueous solution decreases with increase in humidity.
(b) Evaporation produces cooling.
(c) Conversion of solid state to liquid state is called fusion. What is meant by latent heat of fusion?
Or
(a) Which gas is supplied to hospitals in cylinders for artificial respiration?
(b) What does the diffusion of gases tell us about their particles?
(c) Why do liquids easily flow?
Q 14. Why can’t solids be compressed?
(a) The movement of the constituent particles are not estricted.
(b) The inter particle attractive forces are very weak.
(c) The constituent particles are closely packed.
(d) None of the above.
Q 15. Define latent heat of vaporisation. What is the value of latent heat of vaporization for water ?
Or
Write the steps you would use for making tea. Use the words solution, solvent, solute, dissolve, soluble, insoluble, filtrate and residue.