Flowers - Introduction

Introduction

The word flower often conjures up images of familiar blooms that enliven homes, such as roses and sunflowers. Yet flowers do far more than beautify the world. A flowerThe reproductive part of a flowering plant. is the reproductive structure of flowering plants, which are called angiospermsA flowering plant that has its seeds produced within an ovary.. Flowering plants include the familiar blooms as well as grasses, shrubs, and trees. The flowers on plants are widely diverse in size, shape, color, and scent. Flower sizes range from the Wolffia, which can fit through the eye of a sewing needle, to the Titan Arum, a cone-shaped flower that can tower 9 feet (2.7 meters). Some flowers resemble insects, and others sport brightly colored petals. Yet all flowers share the same key function: to make seeds to give rise to a new generation of the plant.

The evolution of flowers supplied many advantages for plant survival and thus, life on Earth. Flowers provide protection for seeds and a food source for animals. In return for food, the animals supply genetic variation to the flower. Mixing up the genetic material allowed flowers to develop new features that led to plants increasing in types and numbers. First appearing on Earth about 145 million years ago during the era of dinosaurs, today about 90 percent of plants are flowering plants.