Trees are greenish. They are greenish at the tip too.How does the water rise upward in a tree or plant against the force of gravity?

How does the trees increase their girth ?

How does Rhytidome protect the plant against forest fire?

A heavy box is kept on a smooth inclined plane and is pushed up by a force F acting parallel to the plane. Does the work done by the force F as the box goes from A to B depend on how fast the box was moving at A and B? does the work by the force of gravity depend on this?

The force of buoyancy exerted by the atmosphere on a balloon is B in the upward direction and remains constant. The force of air resistance on the balloon acts opposite to the direction of velocity and is proportional to it. The balloon carries a mass M and is found to fall down near the earth's surface with a constant velocity v. How uch mass hsould be removed from teh balloon so that it may rise with a constant velocity v?

Vanda is an epiphyte. Epiphytes are the plants growing on branches of trees. They do not have direct contact with soil. How they obtain water for its photosynthetic activity ?

Assertion (A) : Sap wood is vital to the plant but heart wood is not . Reason (R ) : When the heart wood of the tree is destroyed, no vital function of the plant is affected , when the sap wood is destroyed the plant will die, conduction of water is blocked.

A block of wood is floating on water at 0^(@)C with a certain volume 'V' above the water level. The temperature of water is slowly raised to 20^(@)C . How does the volume 'V' change with the rise in temperature ?