A flower containing a pistil, stamen, calyx, and corolla – Complete flower. When a flower consists of essential whorls pistil and stamen and accessory whorls calyx and corolla, the flower is said to be complete.
The collective term for the petals of a flower- Corolla. The corolla is a accessory whorl which consist s of its unit called petal.
It has pistils, but no stamens - Female flower. A flower with only pistil is called unisexual pistillate flower.
A stalk which supports the anther – Filament. A typical stamen consists of an anther, connective and a filament.
A flower that lacks one or more of the following parts: pistil, stamen, calyx, or corolla corolla.—Incomplete flower. A flower which lacks any of the essential or accessory whorl is called incomplete flower.
A flower that has male parts only – Male flower. A flower with only stamen is called unisexual staminate flower.
A spore produced by meiosis – Meiospores. Spores can produced by mitosis or meiosis. If it is produced as a result of mitosis it is said to be mitospores.
I believe the answer you are looking for has to do with cells, they are the basic building block of life and are the smallest life that can support itself.