Although most of us have a good idea what fruits and vegetables are when we eat them, it would be difficult provide a definition for someone of just what makes one food a vegetable and another a fruit. For a botanist, the definitions are easier; a fruit is a reproductive structure of an angiosperm which develops from the ovary and accessory tissue, which surrounds and protects the seed. Fruits are important in seed dispersal. A vegetable is a part of one of the vegetative organs of the plant: roots, stems or leaves, or shoot systems. There are a few "vegetables which are difficult; broccoli and cauliflower are inflorescence buds, and artichokes are the entire inflorescence. Since flowers, the reproductive organ of the plant produce fruits and seeds, perhaps those vegetables which are inflorescences are more similar to fruits than they are vegetables. No matter what we call our nutritious dietary components, in botany what constitutes a fruit is straightforward, and this lab looks at the structure and classification of fruits.
The process of fertilization initiates both seed and fruit development. While seeds develop from the ovules, the ovary tissue undergoes a series of complex changes which result in the development of the fruit. Many fruits are "fleshy" and contain sugars which attract animals who then disperse the enclosed seeds to new locations. Other, non-fleshy, fruits use other mechanisms for seed dispersal. In some plants, fruits can develop without fertilization. This is called parthenocarpy, and such fruits are seedless. As the ovary develops into a fruit, its wall often thickens and becomes differentiated into three, more or less distinct, layers. The three layers together form the pericarp, which surrounds the developing seed or seeds.
The three fruit layers are:
• Exocarp, the outermost layer often consisting of only the epidermis
• Mesocarp, or middle layer, which varies in thickness
• Endocarp, which shows considerable variation from one species to another
Materials Required per pair of students and for Demonstration
• Fresh snap beans or garden peas. Other available legumes may be substituted.
• Dry and soaked corn grains
• Tomatoes, cranberries or grapes
• Peaches, plums, or cherries
• Apples, pears, or quinces
• In addition, an assortment of various kinds of fruits that are available should be available for demonstration. Dry and fleshy fruits of different types should be provided, as should aggregate and multiple fruits.
Exercise 1 Classifying Fruits
All fruits may be classified into three major groups on the basis of the number of ovaries and the number of flowers involved in their formation. The following outline includes most of the common types of fruits. A simple key to classifying fruits is provided here. Use these descriptions and the "Key to Fruit Types" provided to identify the types of fruits you will be observing in the lab.
A. Simple Fruits.
Simple fruits develop from a single matured ovary in a single flower. Accessory fruits have some other flower part united with the ovary.
1. Fleshy Fruits, pericarp fleshy at maturity
a. Berry, consisting of one or more carpels with one or more seeds, the ovary wall fleshy
(1) Pepo (an accessory fruit), a berry with a hard rind, the receptacle partially or completely enclosing the ovary
(2) Hesperidium, a specialized berry with a leathery rind
b. Drupe, a stone fruit, derived from a single carpel and containing (usually) one seed. Exocarp a thin skin
c. Pome (an accessory fruit), derived from several carpels, receptacle and outer portion. of pericarp fleshy, inner portion of pericarp papery or cartilaginous, forming a core
d. Hip (an accessory fruit), several separate carpels enclosed within the fleshy or semi-fleshy receptacle
2. Dry Fruits, pericarp dry at maturity
a. Dehiscent fruits, those which dehisce or split open when fully mature
(1) Follicle, composed of one carpel and splitting along a single suture.
(2) Legume, composed of a single carpel and splitting along two sutures
(3) Capsule, composed of several carpels and opening at maturity in one of four ways:
(a) Along the line of carpel union (septicidal dehiscence)
(b) Along the middle of each carpel (loculicidal dehiscence)
(c) By pores at the top of each carpel (poricidal dehiscence)
(d) Along a circular, horizontal line (circumscissle dehiscence)
III. Identification of Miscellaneous Fruits
There is a key for the identification of fruits at the end of this exercise. Study the various fruits available in the laboratory, having your instructor name them for you if necessary, and record your information on each one on the Table provided. Label the drawings of all of the fruits you have identified.
1 votes Thanks 1
alexisjoynoveloso16
all i know is that my teacher discussed sepals ( ̄ε(# ̄)☆╰╮o( ̄皿 ̄///)
GMilky
that is not our lesson, and this is our lesson "Lesson 8: Identify the parts of the flower." and "Lesson 9: Describe the parts and functions of a flower."
The main difference between sepals and petals is that sepals are the green colour, leaf-like structures that form the outermost whorl whereas petals are the bright-colored petaloid structures which form the inner whorl.
Answers & Comments
Fruit Types and Classification of Fruits
Introduction
Although most of us have a good idea what fruits and vegetables are when we eat them, it would be difficult provide a definition for someone of just what makes one food a vegetable and another a fruit. For a botanist, the definitions are easier; a fruit is a reproductive structure of an angiosperm which develops from the ovary and accessory tissue, which surrounds and protects the seed. Fruits are important in seed dispersal. A vegetable is a part of one of the vegetative organs of the plant: roots, stems or leaves, or shoot systems. There are a few "vegetables which are difficult; broccoli and cauliflower are inflorescence buds, and artichokes are the entire inflorescence. Since flowers, the reproductive organ of the plant produce fruits and seeds, perhaps those vegetables which are inflorescences are more similar to fruits than they are vegetables. No matter what we call our nutritious dietary components, in botany what constitutes a fruit is straightforward, and this lab looks at the structure and classification of fruits.
The process of fertilization initiates both seed and fruit development. While seeds develop from the ovules, the ovary tissue undergoes a series of complex changes which result in the development of the fruit. Many fruits are "fleshy" and contain sugars which attract animals who then disperse the enclosed seeds to new locations. Other, non-fleshy, fruits use other mechanisms for seed dispersal. In some plants, fruits can develop without fertilization. This is called parthenocarpy, and such fruits are seedless. As the ovary develops into a fruit, its wall often thickens and becomes differentiated into three, more or less distinct, layers. The three layers together form the pericarp, which surrounds the developing seed or seeds.
The three fruit layers are:
• Exocarp, the outermost layer often consisting of only the epidermis
• Mesocarp, or middle layer, which varies in thickness
• Endocarp, which shows considerable variation from one species to another
Materials Required per pair of students and for Demonstration
• Fresh snap beans or garden peas. Other available legumes may be substituted.
• Dry and soaked corn grains
• Tomatoes, cranberries or grapes
• Peaches, plums, or cherries
• Apples, pears, or quinces
• In addition, an assortment of various kinds of fruits that are available should be available for demonstration. Dry and fleshy fruits of different types should be provided, as should aggregate and multiple fruits.
Exercise 1 Classifying Fruits
All fruits may be classified into three major groups on the basis of the number of ovaries and the number of flowers involved in their formation. The following outline includes most of the common types of fruits. A simple key to classifying fruits is provided here. Use these descriptions and the "Key to Fruit Types" provided to identify the types of fruits you will be observing in the lab.
A. Simple Fruits.
Simple fruits develop from a single matured ovary in a single flower. Accessory fruits have some other flower part united with the ovary.
1. Fleshy Fruits, pericarp fleshy at maturity
a. Berry, consisting of one or more carpels with one or more seeds, the ovary wall fleshy
(1) Pepo (an accessory fruit), a berry with a hard rind, the receptacle partially or completely enclosing the ovary
(2) Hesperidium, a specialized berry with a leathery rind
b. Drupe, a stone fruit, derived from a single carpel and containing (usually) one seed. Exocarp a thin skin
c. Pome (an accessory fruit), derived from several carpels, receptacle and outer portion. of pericarp fleshy, inner portion of pericarp papery or cartilaginous, forming a core
d. Hip (an accessory fruit), several separate carpels enclosed within the fleshy or semi-fleshy receptacle
2. Dry Fruits, pericarp dry at maturity
a. Dehiscent fruits, those which dehisce or split open when fully mature
(1) Follicle, composed of one carpel and splitting along a single suture.
(2) Legume, composed of a single carpel and splitting along two sutures
(3) Capsule, composed of several carpels and opening at maturity in one of four ways:
(a) Along the line of carpel union (septicidal dehiscence)
(b) Along the middle of each carpel (loculicidal dehiscence)
(c) By pores at the top of each carpel (poricidal dehiscence)
(d) Along a circular, horizontal line (circumscissle dehiscence)
III. Identification of Miscellaneous Fruits
There is a key for the identification of fruits at the end of this exercise. Study the various fruits available in the laboratory, having your instructor name them for you if necessary, and record your information on each one on the Table provided. Label the drawings of all of the fruits you have identified.
Answer:
The main difference between sepals and petals is that sepals are the green colour, leaf-like structures that form the outermost whorl whereas petals are the bright-colored petaloid structures which form the inner whorl.