May L. Medenilla1,2,3 1BS Biology Graduate, Polytechnic University of the Philippines 2 MS Biology Student, Centro Escolar University

3Instructor, Centro Escolar University

Outline

• Fruit • How are they formed?

• Function

• Types • Simple

• Multiple

• Accessory

• Aggregate

• Dispersal

From ovary to fruit

• The ovary of the flower contains the ovules.

• As fertilized ovules develop into seeds, the ovary wall develops into the fruit.

Fruit anatomy

Fruit

• In science, the term “fruit” refers to a mature ovary that contains seeds.

• Protects the seeds that lie within

• The excess food prepared by leaves gets stored around the seeds to form the fleshy part of the fruit.

• DEHISCENT- fruits crack open along two seems and shed their seeds into the environment when the fruit is ripe.

• INDEHISCENT fruit retain their seeds and do not crack open after ripening.

Fruit

• 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

Fruit

• Simple • Fleshy • Dry

• Multiple

• Aggregate

• Accessory

Fruit-SIMPLE

Fruit

•Fleshy Fruit – A simple fruit which is soft and pulpy at maturity. • Berry. The Pericarp is soft and fleshy • Drupe. The exocarp and the mesocarp are soft and

fleshy, but the endocarp and indehiscent.

Seed

Berry (simple fruit) A simple, fleshy fruit in which the fruit wall is soft throughout. Tomato (Lycopersicon lycopersicum)

Fig. 9-12a, p. 187

Single seed inside stone

Drupe (simple fruit) A simple, fleshy fruit in which the inner wall of the fruit is a hard stone.

Peach (Prunus persica)

Fig. 9-12b, p. 187

Fruit-DRY

Fruit

• Dry Fruit – This is dry and hard at maturity. This is of two types, the dehiscent and indehiscent

• Capsule. Composed of two or more fused carpels

• Legume. This develops from one carpel with two sutures

• Follicle. This develops from one carpel with one sutures

• Silique. This develops from two carpels separating at maturity.

• Achene. This is a fruit with only one seed, the ovary wall and seed coat of which are separable.

Split-open suture

Seed

Capsule (simple fruit) A simple, dry fruit that splits open along two or more sutures or pores to release its seeds; fruit is formed from ovary that consists of two or more carpels.

Iris (Iris)

Fig. 9-12e, p. 187

Seed

Legume (simple fruit) A simple, dry fruit that splits open along two sutures to release its seeds; fruit is formed from ovary that consists of a single carpel.

Green bean (Phaseolus vulgaris)

Fig. 9-12d, p. 187

Seed

Follicle (simple fruit) A simple, dry fruit that splits open along one suture to release its seeds; fruit is formed from ovary that consists of a single carpel.

Milkweed (Asclepias syriaca)

Fig. 9-12c, p. 187

Single seed

Seed coat

Achene (simple fruit) A simple, dry fruit in which the fruit wall is separate from the seed coat.

Sunflower (Helianthus annuus)

Fig. 9-12g, p. 187

Fruit

• Dry Fruit – This is dry and hard at maturity. This is of two types, the dehiscent and indehiscent

• Caryopsis or Grain. One seeded fruit, the ovary wall and seed coat of which are not separable

• Samara. Has one or two seeds. Characterized by the pericarp having wing-like extensions.

• Nut. One seeded fruit from a compound ovary.

• Schizocarp. Two carpels that separate at maturity.

Fused fruit wall and seed coat

Single seed

Caryopsis (simple fruit) A simple, dry fruit in which the fruit wall is fused to the seed coat.

Wheat (Triticum)

Fig. 9-12f, p. 187

Woody fruit wall

Single seed

Scale-covered cup

Nut (simple fruit) A simple, dry fruit that has a stony wall, is usually large, and does not split open at maturity.

Oak (Quercus)

Fig. 9-12h, p. 187

Types of dry fruits

Legume

(Bean pod)

Capsule

(Poppy)

Achene

(Sunflower) Silique

(Money Plant)

Follicle

(Columbine) Nut

(Hazelnut)

Fruit

• Multiple Fruits – This is a fruit that develops from ovaries of many flowers at a common axis.

• Aggregate Fruit – This develops from separate simple fruits of a flower.

• Accessory Fruit – This is a kind of fruit with other structures other than the major parts.

MULTIPLE FRUIT

• Fruit that develops from many ovaries of many flowers growing in proximity on a common axis

• Carpels of closely associated flowers fuse, or grow together

• Example: pineapple

Multiple Fruit

Seed

Mulberry (Morus)

Multiple fruit A fruit that develops from the ovaries of a group of flowers.

Fig. 9-12j, p. 187

AGGREGATE FRUIT

• Fruit that develops from a single flower with many separate ovaries

• Several separate carpels fuse, or grow together

• Example: raspberry

Aggregate Fruit

Seed

Aggregate fruit A fruit that develops from a single flower with several to many pistils (i.e., carpels are not fused into a single pistil).

Blackberry (Rubus)

Fig. 9-12i, p. 187

ACCESSORY FRUIT

• Fruit whose fleshy part is composed primarily of tissue other than the ovary

• Example: strawberries

Accessory Fruit

Enlarged floral tube

Ovary wall Seed

Apple (Malus sylvestris)

Accessory fruit A fruit composed primarily of nonovarian tissue (such as the receptacle or floral tube).

Fig. 9-12k, p. 187

Fruit dispersal

• The form of the fruit gives clues about its dispersal. • Small, dry fruits with “wings” or “parachutes” may be

wind-dispersed. • Fleshy fruits are often animal dispersed. • Explosive fruits can fling seeds away. • Floating fruits may be water dispersed.

How are these fruits dispersed?

Dandelion Coconut

Maple

Cocklebur Jewelweed