A fruit develops from one or more carpels. Usually only part of the gynoecium, the ovary, develops into a fruit; the style and stigma wither. Accessory (extracarpellary or noncarpellary) structures may be closely associated with the carpel or carpels and display various degrees of adnation (fusion) to them, thus becoming part of the fruit. Such accessory parts include sepals (as in the mulberry), the bases of sepals, petals, and stamens united into a floral tube (apple, banana, pear, and other species with inferior ovaries), the receptacle (strawberry), the pedicel and receptacle (cashew), the peduncle (fleshy part of the fig), the involucre composed of bracts and bracteoles (walnut and pineapple), and the inflorescence axis (pineapple).
A fruit derived from only carpellary structures is called a true fruit, or, because it develops from a superior ovary (one inserted above the other floral parts), a superior fruit (corn, date, grape, plum, and tomato). Fruits with accessory structures are called accessory (or inaptly, false or spurious) fruits (pseudocarps), or, because of their frequent derivation from inferior ovaries (inserted below the other floral parts), inferior fruits (banana, pear, squash, and walnut).
Fruits can be characterized by the number of ovaries and flowers forming the fruit. A simple fruit is derived from one ovary (tomatoes, pomegranates, grapes, watermelon, peach, pear, apples), an aggregate fruit from several ovaries of one flower (magnolia, rose, and strawberry). A multiple (collective) fruit is derived from the ovaries and accessory structures of several flowers consolidated into one mass (fig, pandan, pineapple, and sweet gum).
The fruit wall at maturity may be fleshy or, more commonly, dry. Fleshy fruits range from soft and juicy to hard and tough. Dry fruits may be dehiscent, opening to release seeds, or indehiscent, remaining closed and containing usually one seed per fruit. Dry fruits include grains (rice, corn, wheat, etc.) dandelions, sunflower seeds, nuts (acorns, peanuts, hickory nuts, etc.), and legumes (peas, beans, etc.). Fleshy fruits are rarely dehiscent.
The pericarp is the fruit wall developed from the ovary. In true fruits, the fruit wall and pericarp are synonymous, but in accessory fruits the fruit wall includes the pericarp plus one or more accessory tissues of various derivations. Besides the fruit wall, a fruit contains one or more seed-bearing regions (placentae) and often partitions (septa). If one were to examine and identify various structures of a fruit then a better understanding of angiosperms will be achieved.
Tomato, Pomegranate, Lemon, Avocado, Apple, Strawberry, Walnut, Pineapple, Seedless Watermelon, and Coconut
Fruit Battery Device (Lemon Required)
Mystery Fruit: TBA
Station Information/Questions (ie 1-5)
Various Tools: ie. Peering Knife, Hammer, Screwdriver, Nut Cracker, Scalpel, Probe, etc
Notebook / Pencil/Pen per student
1. Fruits come in many varieties and classifications; however, they each have similar tissue anatomy. For each of the fruits, read the information about them to help understand the anatomy and perhaps help answer some questions.
2. After the entire group has read the information. Cut the fruit as directed and examine the structures. Share the responsibility of the dissection amongst members of your group. Use the diagram(s) to help identify the main parts; plus, any
others. Some fruits may need to be shared amongst the stations/groups or cut already.
3. Once you have completed the dissection, answer the questions pertaining to the fruit on a separate sheet of notebook paper labeled “Flesh Fruit Lab”. Be sure to place your name on the paper and title each section you go to.
4. Clean your table accordingly and dispose of the fruit that you examined in the trash.