3: Fruit

Question 1

What is a fruit?

Answer 1

a mature ovary that contains a seed

Question 2

T or F: fruit provides nutrients for the seed

Answer 2

FALSE

Question 3

What is the function of the fruit around the seed?

Answer 3

It is a means for seed dispersal because animals will ingest fleshy fruits and deposit them elsewhere ready to germinate or animal fur/wind will pick up and relocate dry fruits

Question 4

What are the 4 kinds of fruits?

Answer 4

1. Simple fleshy fruits
2. Dry fruits
3. Aggregate fruits
4. Multiple fruits

Question 5

Explain what simple fleshy fruits are. What are some characteristics of the flower ovary it was derived from?

Answer 5

Fruits that are fleshy/juicy and edible when mature. They develop from a flower with a single pistil, and they will rot or get eaten by animals to disperse seeds.

The ovary can be derived from a single carpel (simple ovary) or multiple carpels (compound ovary).

The ovary can be superior or inferior in the flower.

The ovary can develop into the fruit itself or other parts of the flower may develop with it

Question 6

What are the three layers in a mature fruit? Describe each. What is the collective term for all 3?

Answer 6

1. exocarp: outer layer/wall of ovary becomes the skin of the fleshy fruit
2. mesocarp: middle layer/wall of ovary that will become the fleshy part we eat (usually)
3. endocarp: the inner layer/wall of ovary, usually where the seed is held

Collective: Pericarp

Question 7

What are the 5 groups of fleshy fruits?

Answer 7

1. True berries
2. Hesperidium (berry-like)
3. Pepo (berry-like)
4. Pome
5. Drupe

Question 8

What are the characteristics of true berries and give examples

Answer 8

• simple fleshy fruits
• soft throughout with thin easily peeled skin when mature
• contain more than one seed (with some exceptions)
• multiple carpels with locules = usually develop from a compound ovary
• the entire pericarp is fleshy, making it difficult to distinguish between the mesocarp and endocarp

ex. Grapes, tomatoes, kiwi, bananas, avocados, dates, peppers, eggplants

Question 9

Define parthenocarpic berries and give an example

Answer 9

Berries that do not have seeds, the exception to the characteristic that makes true berries.

Ex. Bananas, but they have been selectively modified to not have seeds, their wild ancestor did have seeds

Question 10

What are the characteristics of Hesperidium fruits? Give some examples

Answer 10

They are berry-like, simple, fleshy fruits that are:

• soft inside
• leathery exteriors with aromatic oil cavities in skin
• contain multiple carpels filled with sacs containing juice
• contain multiple seeds within the carpels = compound ovary

ex. grapefruits, limes, oranges, lemons

Question 11

What are some characteristics of Pepo fruits? Give some examples

Answer 11

They are berry-like, simple, fleshy fruits that are:

• soft throughout
• have a hard/thick outer skin (rind) that is composed of receptacle tissues and cannot be peeled off
• contain many seeds clustered in the middle
• many carpels = compound ovary

ex. melons, cucumber, pumpkins, squashes

Question 12

What are some characteristics of Pome fruits? Give some examples

Answer 12

• they are SIMPLE fleshy fruits
• they are derived from a flower with an inferior ovary embedded within the floral tube. The ovary will become the core and the floral tube will expand around the ovary to form the accessory tissue/hypanthium which is the fleshy part animals eat.
• endocarp is leathery or papery right around the seeds

ex. apples, pears, quinces

Question 13

Define hypanthium

Answer 13

The floral tube outside the ovary that becomes the fleshy part of pome fruits (such as apples) that animals eat

Question 14

What are the characteristics of a Drupe? Give examples

Answer 14

• simple, fleshy fruit
• usually contain only one seed enclosed in a hard, stony endocarp (usually a pit)
• usually develops from flowers with a superior ovary containing a single ovule
• mesocarp is not always fleshy (ex. coconut husks are the mesocarp and exocarp)

ex. coconuts, stone fruits (peaches, cherries, nectarines, plums, olives, almonds)
- almond seeds grow with husks too that are removed before marketing, then the seed that we consume is enclosed in a hard endocarp that must be cracked

Question 15

Define placenta

Answer 15

the fleshy tissue in some fruits where the seeds are attached
ex. in bell peppers

Question 16

Define locule

Answer 16

the cavity within the fruit where the seeds are located

Question 17

Explain what dry fruits are. What are the two kinds?

Answer 17

Fruits whose mesocarps are dry at maturity.

1. Dehiscent
2. Indehiscent

Question 18

Explain what dehiscent fruits are and list the 5 groups

Answer 18

Dry fruits that split at maturity

1. follicle
2. legume
3. silique
4. silicone
5. capsule

Question 19

Explain what indehiscent fruits are and list the 5 groups

Answer 19

Dry fruits that do not split at maturity, so the SINGLE seed remains fused with the pericarp

1. nut
2. caryopsis (grain)
3. samara
4. achene
5. schizocarp

Question 20

What are the characteristics of follicle fruits? Give examples

Answer 20

Dry, dehiscent fruits that split along ONE side or seam of the fruit only to expose the seeds.
Ex. milkweed, peony, columbine

Question 21

What are the characteristics of legumes? Give examples

Answer 21

Dry, dehiscent fruits that split along TWO sides or seams of the fruit.

ex. peas, beans, lentils, carob, mesquite, most of the legume family (but not peanuts)

Question 22

What are the characteristics of silique fruits? give examples

Answer 22

Dry, dehiscent fruits that split along TWO sides/seams of the fruit but the seeds are attached or embedded to a central partition which becomes exposed when the fruit splits
* very slender and long *

ex. brassicas

Question 23

What are the characteristics of silicles? Give examples

Answer 23

Dry, dehiscent fruits that split along TWO sides/seams of the fruit but the seeds are attached or embedded to a central partition which becomes exposed when the fruit splits
* wide and circular *

ex. shepherd’s purse (brassica)

Question 24

What are the characteristics of capsules? Give examples

Answer 24

• dry, dehiscent fruits that are most common
• contain at least 2 carpels and can split in a variety of ways

ex. Orchids, poppies, lilies, rhododendrons

Question 25

What are the characteristics of nuts? give examples

Answer 25

Dry, dehiscent fruits that contain one seed - the pericarp is very hard and woody ex. acorns, hazelnuts

Question 26

What are the characteristics of achenes? Give examples

Answer 26

Dry, dehiscent fruits - only the base of the seed is attached to the pericarp, making the husk (pericarp) easy to separate from the seed ex. sunflower 'seeds', buttercup, buckwheat, dandelions

Question 27

What are the characteristics of samaras? Give examples

Answer 27

Dry, dehiscent fruits - the pericarp surrounding the seed extends out into a wing structure or membrane, aiding in dispersal ex. maples produce samaras in pairs ex. tree of heaven, elms, ashes produce samaras in singles

Question 28

What are the characteristics of caryopsis (grains)? Give examples

Answer 28

Dry, dehiscent fruits - the pericarp is tightly fused with the seed and cannot be separated ex. all members of Grass family including corn, wheat, rice, oats, barley

Question 29

What are the characteristics of schizocarps? Give examples

Answer 29

Dry, dehiscent fruits - they are composed of two fused twin fruits that upon maturing will break into two separate segments containing a single seed each ex. most of the Apiaceae (parsley) family like dill, fennel, carrot, anise, caraway

Question 30

Explain what aggregate fruits are and give examples

Answer 30

Compound fruits derived from a SINGLE FLOWER with MULTIPLE PISTILS. Each pistil will develop into an individual tiny drupe and as the fruit matures, the individual drupes will fuse into one unit on a single receptacle ex. raspberries, blackberries, strawberries (special case)

Question 31

Explain what multiple fruits are and give examples

Answer 31

Compound fruits derived from MANY FLOWERS, each with a single pistil, in a single inflorescence. As the flowers mature separately into fruitlets, they will develop together to form a single larger fruit ex. mulberry, pineapples, figs

Question 32

What are some methods of seed dispersal for fruits?

Answer 32

1. wind (winged or plumed fruits) - ex. samaras 2. ejection from seed pods when disturbed - ex. achenes 3. water (ability to float long distances) - ex. coconuts 4. animals can: - ingest the attractive fruits - store the fruit in caches - pick up the fruit or seeds on their fur/hair/feet

Question 33

What kind of fruit is an orange?

Answer 33

hesperidium - fleshy

Question 34

What kind of fruit is an apple?

Answer 34

pome - fleshy

Question 35

What kind of fruit is a strawberry?

Answer 35

aggregate - fleshy

Question 36

What kind of fruit is a grape?

Answer 36

berry - fleshy

Question 37

What kind of fruit is a peach?

Answer 37

drupe -fleshy

Question 38

What kind of fruit is a watermelon?

Answer 38

pepo - fleshy

Question 39

What does the outer flesh between the core and skin of a pome fruit (like an apple) come from?

Answer 39

the floral tube or hypanthium tissue (accessory tissue)

Question 40

what is the botanical term for the 'skin' or outside of the ovary wall?

Answer 40

Exocarp

Question 41

What is the term for the fruit types derived from a solitary flower that has more than one pistil (ovary)?

Answer 41

Aggregate

Question 42

What is the botanical term for the hard pit inside of a drupe fruit called?

Answer 42

endocarp

Question 43

What is the botanical term for the fleshy edible tissue between the skin and pit of a drupe?

Answer 43

mesocarp

Question 44

Which of the following dry fruit types does NOT split at maturity? a) samaras b) follicles c) legumes d) capsules

Answer 44

a) samaras - the pericarp needs to soften and rot in order to release the seed

Question 45

Compare & contrast (2 differences, 1 similarity) aggregate and multiple fruits. Give examples of each

Answer 45

SIMILARITY: Aggregate and multiple fruits are both types of compound fruits because they are derived from multiple ovaries (either within a single flower or multiple flowers with single ovaries = many pistils) DIFFERENCE: 1. Aggregate fruits are derived from a single flower, whereas multiple fruits are derived from multiple flowers in an inflorescence 2. Aggregate fruit flowers contain multiple pistils (ovaries) that each form little fruits/drupelets and mature into one single fruit - ex. raspberries. Whereas, multiple fruit flowers each contain a single pistil and each flower, as the fruit matures, will coalesce into one large fruit - ex. pineapples

Question 46

Difference between a simple pistil and compound pistil. Which fruits are in which category?

Answer 46

SIMPLE: one flower, one pistil, one carpel ex. follicles, legumes, achenes, nuts, grains, schizocarps, samaras, drupes COMPOUND: one flower, one pistil, 2+ carpels ex. silicles, siliques, capsules, most berries, pomes, pepos, hesperidiums