Inside the perianth is the androecium house of man , a whorl composed of stamens. Each stamen has a long filament holding up pollen sacs called anthers. Inside the androecium is the gynoecium house of woman , which is composed of carpels. Each carpel has an ovary at the base where ovules are housed. The style emerges from the ovary and is topped by the stigma. Pollen grains land on the stigma and must grow a tube down the style to reach the ovule and complete fertilization. All of these whorls attach to an area called the receptacle , which is at the end of the stem that leads to the flower.
This stem is called the peduncle. In the case of an inflorescence, where multiple florets are produced in place of a single flower, the stems leading to the florets are called pedicels. In the diagram of the flower below, add labels for all of the bolded terms above and assign each whorl a different color.
Make a key for the colors and whorls. Flowers that have multiple lines of symmetry like a starfish are radially symmetrical , also called actinomorphic. Flowers with only a single line of symmetry like you are bilaterally symmetrical , also called zygomorphic.
Flowers with parts in sets of 3 are generally monocots. Flowers with parts in sets of 4 or 5 are generally eudicots. Sometimes these parts are fused together and can be difficult to count.
For example, in the diagram of the lily above, there are three fused carpels. You would only be able to determine this by counting the lobes on the stigma or by looking at a cross section of the ovary to count the different compartments called locules.
Many wind pollinated flowers have evolved to be either male or female, containing either an androecium or gynoecium, but not both. These flowers are called imperfect , while flowers containing both internal whorls are called perfect. Flowers that contain all whorls are called complete.
Figure 2. The corn plant has both staminate male and carpellate female flowers. Staminate flowers, which are clustered in the tassel at the tip of the stem, produce pollen grains. Carpellate flower are clustered in the immature ears. Each strand of silk is a stigma. The corn kernels are seeds that develop on the ear after fertilization. Also shown is the lower stem and root.
If the anther is missing, what type of reproductive structure will the flower be unable to produce? The ovary, which may contain one or multiple ovules, may be placed above other flower parts, which is referred to as superior; or, it may be placed below the other flower parts, referred to as inferior Figure 3.
Figure 3. The a lily is a superior flower, which has the ovary above the other flower parts. Improve this page Learn More. Skip to main content. Module 9: Plant Reproduction. Search for:. Flower Structure Learning Outcomes Describe the components of a complete flower. Practice Question If the anther is missing, what type of reproductive structure will the flower be unable to produce?
Show Answer Pollen or sperm. Show Answer Carpellate. Show Answer Staminate. Try It. Did you have an idea for improving this content?
0コメント