What is the job of a flower stalk in a flower?

The normal flower has three basic functions:

1. It provides a platform for the sexual reproductive system of the plant (androecium - male and gynoecium - female) - both monoecious and diecious flowers

2. It provides a mechanism to attract pollinators to facilitate pollination (petals) - monoecious flowers and diecious flowers

3. It provides a platform for fertilized ovules to develop and be distributed as fruit and seeds - monoecious flowers and female diecious flowers only.

Monoecious = having both sexes (male and female) on the same flower

Diecious = having separate sexed flowers (male flowers and female flowers)