An introduction to flowers

Flowers are plants’ devices for reproduction, the sexual organs of angiosperms (the flowering plants) and since very early times have kept the attention of humans. Their incredible diversity is probably the most distinctive feature for the identification of plants, having a special importance for botanists. However, not only botanists (or pollinators) have been attracted to flowers – they have a constant presence in our society having different meanings and we heard about them in history, traditional medicine, religion, and even artists from all fields have been inspired by their beauty.

To understand flowers’ morphology is to understand plants’ evolution and co-evolution with their pollinators. Maybe some of you are not interested on the evolution or morphology of flowers, but plants are everywhere, and by giving attention to these beings you will probably find out some surprising things. Although plants are still and silent, they have other ways to communicate with us – we just need to understand how they do it!

My aim with these stories is to explain the floral morphology, development and evolution by using a language understandable to all interested. This might be a nice way for you to get to know better the organization of structures in the flower itself.

On this first post, I will explain a little bit about the floral morphology and the basic floral characters – it will be easier for you to understand the stories and you can always take a look at this first post to remember what the structures are.

Flowers are formed by fertile and unfertile parts. The unfertile parts are usually to protect the fertile ones (sepals, the green and outermost parts of the flower), or to attract the pollinators (petals, which are usually showy and colourful). The fertile parts are in the center of the flower and consist on the male and female parts. The stamens (male organs), are formed by the filament and the anthers (the structures that produce the pollen grains). The female parts are the carpels and are always found in the center of the flower, surrounded by all the other floral structures. Carpels are formed by the ovary (the organ that bears the ovules and that, once fertilized will originate the fruit), the style and the stigma (the structure that receives the pollen grains, which are guided to the ovary to fertilize the ovules). As plants don’t move they have to pollinators (like animals or wind), to take the pollen to the stigma, this is called pollination.

Flowers are not this simple, but this will help you on understanding the basics of the flower morphology. Some flowers have extra structures, others lack structures, and others have modified structures, having a totally different appearance. I will talk about them later, on each story, as different flower have different structures for the most different reasons…