A leaf is modified to carry out relatively several additional functions in

In Nepenthes, the basal half of petiole is modified as phyllode for photosynthesis, the upper half is modified as tendril for climbing and the lamina to trap the insects for insectivory. In Venus-fly-trap, the petiole is for photosynthesis and leaflet for trapping the insect. In Cacti, the complete leaf is modified as spine for protection. In australian acacia only the petiole is left out in a leaf and modified as phyllode for photosynthesis.