Casparian strip is found in the endodermis. The walls of this layer are impervious to water because of the presence of suberin. So, it does not allow movement of water across the endodermis, rather is forced to enter the symplast pathway through cell membranes and reaches the xylem.

Difference between guttation and transpiration is as follows

Guttation	Transpiration
Guttation is the loss of liquid droplets from the plants.	It is the loss of water by a plant in the form of vapours.
Guttated water is a dilute solution of both inorganic and organic substances.	Transpired water is a pure water.
Guttation occurs at the margins and the tips of the leaves.	Transpiration occurs through the general surface of the leaves and the young stem.
Excessive guttation does not cause loss of turgidity.	Excessive transpiration results in wilting in severe cases, could be lethal to plant.

The plant continuously lose water in the vapour form from its body surfaces. It creates a transpiration pull to absorb more and more water from soil through roots. If the plant does not get water in soil, even then loss through transpiration is not stopped, so plant shows wilting sometimes it leads to the physiological wilting (non-recoverable) and plant dies. So, the transpiration is necessary evil.

The three physical properties of water that helps in ascent up to xylem are as given

Cohesive properties	Mutal attraction between molecules
Adhesive properties	Attraction of water molecules to polar surfaces (of tracheids)
Surface tension	Water molecules get attracted to each other more in liquid phase than in gas phase.

If gardener forgets to water the plants, it will start it wilting (a physiological state of plant in which plant leaves droop down). If watered in time, the plant may recover and become normal. But in second condition, if watering is delayed, the plant will not recover as if it reaches at physiological wilting stage, it will not recover and dies.