1. The Reproductive Body: Fruits and Seeds
PBIO 006
Spring 2016
Chapter 6

2. Outline
I. Fruit Types
II. Fruit Dispersal
III. Seed Structure and Germination

3. Ovary to fruit

5. Kinds of Fruits

6. Kinds of Fruits
Simple fruits develop from a single ovary (simple or compound) of a single flower
Fleshy (e.g., tomatoes, lemons, cucumbers, cherry, apple)
Dry, dehiscent (e.g., legumes, like peanuts)
Dry, indehiscent (e.g., sunflower “seeds”)
Aggregate fruits develop from many separate simple pistils in a single flower (e.g., raspberries, strawberries)
Multiple fruits develop from the fusion of ovaries from many separate flowers on an inflorescence (e.g., pineapples)

7. Berry: a simple, fleshy fruit with a soft pericarp
Grapes
Tomato
Blueberry
Kiwifruit

8. Drupe: A simple, fleshy fruit where the pericarp is divided into three layers
Peach, Prunus persica

9. Dry fruits have a woody or papery pericarp
Some dry fruits are dehiscent
Amaryllis capsule
Dry, dehiscent fruits
Milkweed (Asclepias syriaca) follicle

10. Dry, indehiscent fruits
Red maple fruit is a samara
Sunflower fruit is an achene
Fruit of the grass family is a grain

11. Kinds of Fruits
Simple fruits develop from a single ovary (simple or compound) of a single flower
Fleshy (e.g., tomatoes, lemons, cucumbers, cherry, apple)
Dry, dehiscent (e.g., legumes, like peanuts)
Dry, indehiscent (e.g., sunflower “seeds”)
Aggregate fruits develop from many separate simple pistils in a single flower (e.g., raspberries, strawberries)
Multiple fruits develop from the fusion of ovaries from many separate flowers on an inflorescence (e.g., pineapples)

12. Aggregate fruit
A raspberry is an aggregate fruit: each little “drupelet” is the product of a separate ovary. Each drupelet contains a single seed.

13. Accessory fruit
strawberry achene
The strawberry is an accessory fruit: the sweet, juicy part is receptacle, not ovary wall! The true fruit part is the achene.

14. Multiple fruits
The pineapple is an example of a multiple fruit: the fruit is derived from the fusion of an entire inflorescence.

16. wind
animal (active)
animal (passive)

17. Fleshy fruits are dispersed by birds and other frugivorous animals.

18. Coconuts are dispersed
by water.

20. Outline
I. Fruit Types
II. Fruit Dispersal
III. Seed Structure and Germination

21. So what is a seed again?
A brief review…

23. (in
central cell)
cell

25. S E D T R U C

26. S cotyledons E D hypocotyl G R M I N A epicotyl T (not visible) O
radicle
lev70065_06_02.jpg
Dicot embryo

27. Germinating peanut seedling
Seed structure
Germinating peanut seedling
epicotyl

28. Seed germination in the common garden bean, a eudicot
Foliage leaves
Cotyledon
Cotyledon
Cotyledon
Figure 38.9 Two common types of seed germination.
Radicle
Seed coat
Seed germination in the common garden bean, a eudicot

29. Chapter 6 Review Questions
Describe the relationship between the ovary and the fruit; between the ovule and the seed.
What is a simple fruit? Describe several different kinds, distinguishing between them.
How do aggregate and multiple fruits differ from simple fruits?
What functions do fruits serve in the life of the plant?
Diagram a seed. What are its principal parts and what functions do they serve?