Tooty Frooty Fruit Types

What is a Fruit?

• A fruit is a propagative unit developing from one or more fertilized egg cells enclosed by integuments and attached to megasporophylls, or a megasporophyll-scale complex, in a strobilus, cone, gynoecium, concrescent gynoecia, or gynoecia that disseminate together at the time it or its seed(s) are dispersed from the plant, or just prior to germination on the plant, and it may also include any other attached scales, bracts, modified branches, perianth, or inflorescence parts

What is a Fruit?

• A fruit is a ripened or mature ovary

• Fruits contain seeds

Review of Basic Floral Morphology

• A typical flower has 4 parts

– Sepals

– Petals

– Stamens

– Pistils

Review of Basic Floral Morphology

• Sepals are the outer green, leaf-like structures

– Function to protect the developing flower bud

• Collectively called the calyx

Review of Basic Floral Morphology

• Petals are the “pretty” parts

– They function to attract pollinators to the flower

• Collectively called the corolla

Review of Basic Floral Morphology

• Stamens are the “male reproductive” parts – They produce pollen,

which contain sperm

• Stamens consist of – Anthers, where pollen is

produced

– Filaments which support the anthers

• Collectively called the androecium

Review of Basic Floral Morphology

• Pistils are the “female” reproductive parts

• They consist of three parts – Stigma

– Style

– Ovary

• Ovaries contain ovules

• Ovules produce eggs

• Collectively called the gynoecium

Review of Basic Floral Morphology

• All the floral parts sit on a base called the receptacle

Reproduction in Flowering Plants

• Reproduction in flowering plants is a 2-step process consisting of

– Pollination

– Fertilization

Pollination

• Pollination is the transfer of pollen from the anthers of a flower to the stigma(s) of another, compatible flower

Fertilization

• Fertilization is the fusion of two gametes

– Eggs produce by ovules in the ovary

– Sperm produced by the anthers

• Results in a zygote

Seed & Fruit Development

• The process of fertilization initiates both seed and fruit development

• While seeds are developing in the ovules, the ovary tissue undergoes a series of changes resulting in the development of the fruit

Seed & Fruit Development

• As the ovary develops into a fruit, its wall thicken and become differentiated into 3, more or less distinct layers

• These 3 layers, together, are called the pericarp

• The pericarp surrounds the developing seed or seeds

Pericarp Layers

• The 3 fruit layers are

– Exocarp: outermost layer; consists mostly of epidermis

– Mesocarp: the middle layer; varies in thickness

– Endocarp: inner layer; shows lots of variation from species to species

Classifying Fruits

• Fruits can be classified into 3 major groups

– Based on the number of ovaries and number of flowers involved in their formation

• Simple fruits

• Aggregate fruits

• Multiple fruits

Classifying Fruits

• Fourth “kind”

– Accessory fruits

• Fruits that develop from tissues surrounding the ovary are called accessory fruits

Simple Fruits

• Simple fruits develop from a single matured ovary in a single flower

Types of Simple Fruits

• Fleshy fruits have pericarps that are fleshy at maturity

– Berry: one or more carpels with one or more seeds; ovary wall fleshy

– Pepo (accessory fruit): a berry with a hard rind; the receptacle partially or completely encloses the ovary

Types of Simple Fruits

• Hesperidium: a specialized berry with a leathery rind

• Drupe: a stone fruit derived from a single carpel and containing (usually) a single seed; the exocarp is a thin skin

Types of Simple Fruits

• Pome (accessory fruit): derived from several fused carpels, receptacle, and outer part of pericarp; fleshy inner part of the pericarp is papery or cartilaginous and forms a core

Simple Fruits

• Hip (accessory fruit): several separate carpels enclosed within the fleshy or semi-fleshy receptacle

Simple Fruits

• Dry fruits have a pericarp that is dry at maturity

– Dehiscent fruits: dehisce or split open at maturity

Simple Fruits Dry Dehiscent Fruits

• Follicle: composed of one carpel and dehiscing along a single suture

Simple Fruits Dry Dehiscent Fruits

• Legume: composed of a single carpel and dehiscing along 2 sutures

Simple Fruits Dry Dehiscent Fruits

• Capsule: composed of several carpels and dehiscing at maturity in one of four ways

Simple Fruits

• Types of capsules

– Septicidal: dehiscing along the line of carpel union

– Loculicidal: dehiscing along the middle of each carpel

– Poricidal: deshiscing by pores at the top of each carpel

– Circumscissile: dehiscing along a circular, horizontal line

Septicidal Capsule

• Dehisces along the line of carpel union

Loculicidal Capsule

• Dehisces along the middle of each carpel

Take me to your leader!

Poricidal Capsule

• Deshisces by pores at the top of each carpel

Circumscissile Capsule

• Dehisces along a circular, horizontal line

Simple Fruits

• Silique: composed of 2 carpels which separate at maturity, leaving a persistent partition between them

Simple Fruits

• Indehiscent fruits: do not open at maturity

– Achene or akene: one-seeded fruit with the seed attached to the fruit at one point only

– Caryopsis or grain: one-seeded fruit in which the seed is firmly attached to the fruit at all possible points

– Samara: one- or two-seeded fruit with the pericarp bearing a wing-like outgrowth; a modified achene

Achene (Akene)

• A one-seeded fruit with the seed attached to the fruit at one point only

Caryopsis (Grain)

• A one-seeded fruit in which the seed is firmly attached to the fruit at all possible points

Samara

• A one- or two-seeded fruit with the pericarp bearing a wing-like outgrowth; a modified achene

Simple Fruits

• Schizocarp: two carpels which separate along the midline at maturity into 2 one-seeded halves, each of which are indehiscent

• Loment: has several seeds which break into one-seeded segments at maturity

• Nut: a hard, one-seeded fruit, generally formed from a compound ovary, with the pericarp hard throughout

Schizocarp

• Two carpels which separate along the midline at maturity into 2 one-seeded halves, each of which are indehiscent

Loment

• Fruit with several seeds which break into one-seeded segments at maturity

Nut

• A hard, one-seeded fruit, generally formed from a compound ovary, with the pericarp hard throughout

Aggregate Fruits

• Aggregate fruits consist of a number of matured ovaries formed in a single flower and arranged over the surface of a single receptacle

• Individual ovaries are called fruitlets

Multiple Fruits

• Multiple fruits consist of mature ovaries of several to many flowers more or less united into a mass

• Multiple fruits are almost always accessory fruits

Accessory Fruits

• Fruits that develop from tissues surrounding the ovary are called accessory fruits

• Accessory fruits generally develop from flowers that have inferior ovaries and the receptacle or hypanthium becomes part of the fruit

• Accessory fruits can be simple, aggregate, or multiple fruits

Accessory Fruits

Fruit Sort