What Is a Perfect Flower?
Amateur botanists may see perfection in any flower, but there is a specific meaning to the term ''perfect flower.'' A perfect flower is one that has all three of these traits:
- It makes and distributes male gametes.
- It makes female gametes.
- It receives male gametes.
What is a gamete? A gamete is a sex cell that will unite with another sex cell during the process of sexual reproduction. In this example, gametes are either male or female and look to pair with the opposite type (male cells look for female cells and vice versa).
So a perfect flower produces both male and female gametes (sex cells). Let's take a look at what this really means.
In the flower world, the male reproductive structures are called stamens, and the female reproductive structures are called pistils. The stamens are made up of two parts: the anther and the filament. The anther is the part of the stamen that produces pollen. Pollen is the male gamete, or sex cell. The filament supports the anther to make pollen available to insects that aid in cross-pollination.
The pistils (remember, these are the female structures) are made up of three parts: the stigma, the style, and the ovary. The stigma is the part that catches the pollen. The style is a tube where caught pollen is transferred from the stigma to the ovary. The ovary is located at the base of the style and this is where eggs (the female gametes, or sex cells) are produced and can combine with the pollen when it's present. When the male and female gametes combine, they form a fertilized seed. Because a perfect flower has both the stamens and the pistils, it is capable of producing its own fertilized seed. It's like sexual reproduction without requiring a partner!
Self vs. Cross-Pollination
When a flower has both male and female reproductive parts and can create its own fertilized seed, it is capable of self-pollination, meaning it doesn't require gametes from another plant to reproduce. Some perfect flowers depend entirely on self-pollination.
On the other hand, some perfect flowers are capable of self-pollination but they still try to avoid it. Instead, they rely on cross-pollination, usually aided with the help of insects like bees. In cross-pollination, an insect will visit a flower and pick up pollen that usually sticks to it, and when the insect flies to the next flower, some of that pollen falls off. If it falls off in the vicinity of a pistil and there's an egg waiting in the ovary, then that egg can become fertilized and a seed will develop.
Perfect flowers that rely on cross-pollination for reproduction may keep their male and female structures physically separated to reduce the risk of self-pollination, or they may produce each gamete at different times. In some cases, a perfect flower will self-pollinate but the seed will not be viable (meaning it's not capable of growing into a new plant).
Now we know that a perfect flower produces both male and female gametes, so it makes sense that an imperfect flower is one that has only male structures and gametes or only female structures and gametes.
Perfect Flower: Examples
Let's look at some examples of perfect flowers. Many of the flowers you encounter on a daily basis have both male and female reproductive structures, making them perfect flowers. These include roses, tulips, lilies, orchids, apples, and cherries, among many others.
Okay, let's review what we've learned about perfect flowers. As we learned, perfect flowers are those that have both male and female reproductive structures. They produce both male and female gametes, which are sex cells that unite with other sex cells during the process of sexual reproduction, and they're capable of receiving male gametes from other flowers. In terms of the, well, terminology, we also learned the following about plant reproductive structures:
- Stamens, which are the male reproductive structures
- Pistils, which are the female reproductive structures
- The anther, which is the part of the stamen that produces pollen
- Pollen, which is the max gamete, or sex cell
- The filament, which supports the anther to make pollen available to insects that aid in cross-pollination
- The stigma, which is the part that catches the pollen
- The style, which is a tube where caught pollen is transferred from the stigma to the ovary
- The ovary, which is located at the base of the style and is where eggs (the female gametes, or sex cells) are produced and can combine with the pollen when it's present
We also learned how some perfect flowers rely solely on self-pollination, meaning they use their male and female gametes to develop fertilized seeds. Other perfect flowers still rely on cross-pollination for reproduction, in which an insect will visit a flower and pick up pollen that usually sticks to it, and when the insect flies to the next flower, some of that pollen falls off, fertilizing a plant's egg cell. Many flowers we are familiar with are examples of perfect flowers, such as roses, lilies, orchids, tulips, apples, and cherries, among others.
To unlock this lesson you must be a Study.com Member.
Create your account
Perfect Flowers: Crossword Puzzle
This activity will assess your knowledge of the definition, structure, and examples of perfect flowers.
Complete the crossword by filling in a word that fits each of the given clues. For this activity, you'll need a printer to reproduce the following page. With a pencil and an eraser, neatly write your answers in the boxes provided.
3. The __________ is essential in the reproduction of flowering plants, for it produces pollen grains.
5. The sexual reproduction in flowering plants involves the production of male and female __________.
8. A discrete female structure at the center of a flower capable of receiving pollen and producing fruit is called the __________.
9. The __________ is the enlarged base of a pistil that produces the egg cells.
10. Self-pollination is when __________ from the same plant arrives at the stigma of the same flower.
1. __________ flowers have both male and female structures, allowing them to self-pollinate.
2. The gluey part of a flower that receives the male gamete during pollination is called the __________.
4. Plants cross-pollinate by using the bright color and alluring fragrances of their flowers to attract __________.
6. A __________ is a specialized structure that contains all the reproductive organs of a plant.
7. The __________ carries the pollen grains from the stigma to the ovary of the flower.
Register to view this lesson
Unlock Your Education
See for yourself why 30 million people use Study.com
Become a Study.com member and start learning now.Become a Member
Already a member? Log InBack