State the four ways in which saliva is useful to us.

State four ways in which machines are useful to us.

List any four ways by which GMO's have been useful for enchanced crop output.

What is vaccination ? Mention the four ways in which vaccines are prepared, giving the name I of one disease for which each type of vaccine is used.

List any four ways in which the antibiotics are being used.

State four ways for the judicious use of energy.

State the use of echo in medical field.

State the units of three variables used in gas laws.

State four physiological function / uses of ethylene.

There are animals, which are useful to us in more than one way. Select an appropriate code to match the animals to untiliy.