Questions

Veins seen in the leaves, serve the function of Transpiration.

Transpiration is the process by which moisture is carried through plants from roots to small pores on the underside of leaves, where it changes to vapor and is released to the atmosphere. 

Both of them are relation ship constraints

A change to the Constitution is called as An Amendment.

An Amendment ::

An Amendment is ratified after two-thirds of the House and Senate approve of the proposal and send it to the states for a vote. That Convention can propose as many amendments as it deems necessary. Then, three-fourths of the states must affirm the proposed Amendment.

Biological Control: This method is very effective. One pest is destroyed by another organism. For example the aphids are killed by lady beetle. The prickly pear is eradicted by cochineal insect. Here the advantage is, one does not use harmful chemicals which may get into the host plants.