Fruits
PLANT SCIENCE
UNIT 2
Fruit
 In flowering plants –
fruit is a mature ripened
_________ that
contains the seeds
 A fruit is defined as a
ripened ovary
 Pericarp – the ovary
wall

May consist of two or three
layers: exocarp, mesocarp,
endocarp
Pericarp
Fruit Types
Simple
Aggregate
Multiple
Simple Fruit
 A simple fruit – develops from a single ovary of a
single flower
 Can be either fleshy or dry when mature
 Simple fleshy fruit

Berry
Simple Fleshy Fruit
Berry – entire fruit wall is soft and fleshy at
maturity. Inside is slimy. Contains no stony layer
but contains one to many seeds.
1.
1.
Examples: Grapes, tomatoes, etc
2. Hesperidium - a berry with a tough, leathery
rind (peel)
2.
Examples: Oranges, lemons, other citrus
Simple Fleshy Fruit
3. Drupe – outer part of fruit wall is soft and fleshy,
inner part is hard and stony. Has a pit.
3.
Examples: Peach, plum, cherries
Simple Fleshy Fruit
4. Pepo – also a fleshy
fruit with a tough outer
rind
 All members of the
squash family:
pumpkin, melon,
cucumber
Simple Fleshy Fruit
5. Pomes: most of the fleshy part of pomes develops
from the enlarged base of the perianth (corolla and
calyx) that has fused with the ovary wall
Examples: Pears, apples
Simple Dry Fruits
 Simple dry fruits are dry (not fleshy) at maturity.
Simple dry fruits that open at maturity include
capsules and legumes
 Capsule – fruit is dry at maturity and splits open
along several seams

Example: Cotton
Simple Dry Fruit
 Legumes are dry at maturity and split open along
__________ seams

Examples: pea pods, bean pods, peanut
Simple Dry Fruits
Simple dry fruits that do NOT
open at maturity include:
 Caryopsis: seed coat is fused
to the ovary wall

Examples: corn, wheat
 Nuts: single-ovary wall and
seed coat remain separate,
ovary wall is very hard

Example: acorn s
Aggregate Fruit
 An aggregate fruit develops from one flower with
many separate pistils/carpels, all ripening
simultaneously

Examples: strawberry, raspberry, blackberry
Multiple Fruit
 Multiple fruit develops from ovaries of several
flowers borne/fused together on the same stalk

Example: pineapple
What is the purpose of the fruit?
 The main function of the fruit is to disperse the seeds
 Dispersal is important because
 It spreads the progeny in order to colonize new environments
 Reduces the chances of predators destroying all of the plant’s
yearly seed production
 Reduces plant competition
 4 types of dispersal
Self Dispersal
 Plants disperse their seeds by forceful ejection –
explosive fruits!
 Witch hazel, squirting cucumber (jet propulsion)
Self Dispersal
 The peanut plant sows
(buries) its own seeds!
 Geocarpic: carpel
grows inside the earth
Wind Dispersal
 Fruit and seeds may have special devices for wind
dispersal
 Plumes catch wind currents: dandelion
 Trees take advantage of their great heights for wind
dispersal. Fruits with wings are used to slow the
descent to land: maple, ash fruit
Water Dispersal
 Fruits and/or seeds use flotation devices to travel by
water
 Fruit may have air spaces, waterproof coverings, and
corky floats

Example: coconuts
Animal Dispersal
 Some dry fruit attach and cling to animals
 Some have velcro-like hooks that cling to animal fur
(burdock, cockleburs)
 Others that sticky substances that stick to host
(mistletoe)
Check it out!
 http://www.vtaide.com/png/seed-dispersion.htm
 Gives more examples of how specific fruits are
dispersed