Plants that bear flowers can be divided up into two groups, dicotyledons and monocotyledons, or dicots and monocots, based on a number of characteristics. A cotyledon is a "seed leaf" or "baby leaf" produced by the embryo of a seed to nourish the plant before the true leaves form. Dicots have two and monocots have one. They also have rather different roots, leaf vein structures and flower parts.
Petals And Sepals
Petals are often the most obvious part of a flower, usually large and colorful. Cicots feature four or five of them, or multiples of these numbers. These attract the insects that pollinate the flowers and may be scented or have lines on them to guide the insect to the center, where the fertile parts of the flower are located. Collectively, they are called the perianth.
Sepals, usually smaller and green, are leaf-like bracts that protect the flower as it develops and matures. Certain flowers, such as dogwood "flowers," feature sepals that are large, look much like petals, and are called tepals. Collectively, they are called the calyx.
The carpel, the female parts of the flower, is made up of the stigma, style, ovary, and ovule. In dicots, these are in fours or fives. It is usually the innermost part of the flower, sitting right at the center.
The stigma is a sticky place at the top of the carpel that holds the pollen, often also having various groves or hairs. It is situated on top of a style, the stalk that raises the stigma up above the ovary. One function of the style is to prevent self-fertilization of the flower by its own pollen.
The ovary is the rounded part at the base of the style that becomes the fruit. If it sits on top of the place where the petals are attached, it is called a superior ovary; if below, with the petals and sepals surrounding it, it is called an inferior ovary. Inside, there are locules in which ovules (fertile "eggs") develop.
The ovule contains one egg cell that, when fertilized, develops into a new plant. It has a gap in its outer covering through which the tube that grows from a pollen grain delivers a sperm cell.
Stamens are the male parts of the flower and are also found in fours or fives. They are made up of a filament and an anther.
The anther is rounded or oval and contains two locules, the fertile area that produces the pollen that is released to the outside through slits or pores. Dicot pollen has three furrows or pores, and monocots have just one.
The filament is the stalk that holds up the anther and, in an unopened flower, delivers nutrients to it as it develops.