Venation refers to the arrangement of veins in a leaf. It is of two types:  

1. Reticulate venation – Veins form a network, found in dicots (e.g., mango).  

2. Parallel venation – Veins run parallel to each other, found in monocots (e.g., grass).  

Phyllotaxy is the arrangement of leaves on a stem or branch. It is of three types:  

1. Alternate – A single leaf grows at each node alternately (e.g., sunflower).  

2. Opposite – Two leaves grow at the same node opposite each other (e.g., guava).  

3. Whorled – More than two leaves grow in a circle at a node (e.g., Alstonia).