1. Flowers, Fruits, and Seeds
Chapter 8
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2. Outline
Dicots versus Monocots
Structure of Flowers
Fruits
Fleshy
Dry
Fruit and Seed Dispersal
Seeds
Germination
Longevity

3. Dicots versus Monocots
Dicots (Magnoliopsida)
Two cotyledons
Flower parts in fours or fives
Leaves with distinct vein network
Vascular cambium present
Vascular bundles in ring
Pollen grain with three apertures
Monocots (Liliopsida)
One cotyledon
Flower parts in threes
Leaves with parallel primary veins.
Vascular cambium absent
Vascular bundles scattered
Pollen grain with one aperture

4. Structure of Flowers
Each flower, which begins as an embryonic primordium that develops into a bud, occurs as a specialized branch at the tip of a peduncle which may have branchlets of pedicles.
Pedicle swells at its tip into a small pad (receptacle).
Other parts of the flower are attached to the receptacle.

5. Structure of Flowers
Outermost whorl typically consists of three to five sepals.
Sepals (calyx) may be fused together.
Next whorl consists of three to many petals (corolla).
Calyx and corolla form the perianth.

6. Structure of Flowers
Several to many stamens are attached to the receptacle around the base of the pistil.
Each stamen consists of a filament with an anther at the top.
Pollen grains developed and disseminated in anthers.

7. Structure of Flowers Pistil consists of Stigma, Style, and Ovary.
Superior Ovary - Calyx and corolla are attached to the receptacle at the base of the ovary.
Inferior Ovary - Receptacle grows up and around the ovary.
Calyx and corolla appear to be attached at the top.

8. Gymnosperms flowers Sago palm, however not a true palm:
The generic name
comes from Greek
Koikas, and means
"a kind of palm".
About 95 species are
currently accepted in the cycad family Cycadaceae.

9. Gymnosperms flowers Polen cones- male strobili Seed cones-
female strobili
Pollen grains

10. Monocot flowers

11. Dicot flowers

12. Structure of Flowers
Inflorescences - Group of several to hundreds of flowers

13. Fruits
Fruit is an ovary and its accessory parts that have developed and matured.
Usually contains seeds.
All fruits develop from flower ovaries and accordingly are found exclusively in flowering plants.

14. Fruits Fruit Regions Exocarp - Skin
Endocarp - Inner boundary around seed(s).
Mesocarp - Fleshy tissue between exocarp and endocarp.
Three regions are collectively called the pericarp.

15. Fruits
Fleshy Fruits
Simple fleshy fruits develop from a flower with a single pistil.
Drupe - Simple fleshy fruit with a single seed enclosed by a hard, stony endocarp, or pit. E.g,; coconuts,apricot, peach,plum, almond

16. Fruits
Berry - Usually develops from a compound ovary and often contains more than one seed. Three types of berries:
True berry is a fruit with a thin skin and a relatively soft pericarp.E.g.;tomatoes, grapes, peppers, eggplants, blueberries, cranberries, pomegrantes.

17. Fruits
Pepos - Relatively thick rinds (Pumpkins).

18. Fruits
Hesperidium – Berry with a leathery skin (citrus family)

19. Fruits
Pomes - Bulk of flesh comes from enlarged floral tube or receptacle that grows up around the ovary. (Apples)
–Acessory fruits: Fruits developed from more than an ovary alone i.e. Pomes, pepos and some berries

20. Fruits
Aggregate Fruits
Derived from a single flower with several to many pistils.
Individual pistils mature as a clustered unit on a single receptacle
Raspberries, Strawberries.

21. Aggregate fruits/Raspberries, blackberries

22. Aggregate fruits/Raspberries, blackberries
Individual pistils

23. Fruits
Multiple Fruits
Derived from several to many individual flowers in a single inflorescence.
Pineapples, Figs, Mulberries

24. Multiple fruits/Pineapples, figs

25. Fruits Dry Fruits That Split at Maturity (Dehiscent)
Follicle - Splits along one side or seam (Milkweed).
Legume - Splits along two sides or seams (Beans, peas,garbanzo beans, lentils,carob, peanuts!).
Silique - Splits along two sides or seams, but seeds are borne on central partition, exposed when the two halves separate (Cabbage, broccoli).
Capsules - Consist of at least two carpels, and split in a variety of ways (Poppies, Lilies).

26. Follicles-Milkweed)
Silicles-Lunaria (Dollar plant)
Capsule-Orchid

27. Fruits Dry Fruits That Do Not Split at Maturity (Indehiscent)
Achene (Sunflower)
Nut (filberts=Hazelnut)
Grain (Poaceae fam.)
Samara( ashes, elms)
Schizocarp (parsley, carrots)

28. Fruits Dry Fruits That Do Not Split at Maturity (Indehiscent)
Schizocarp: Twin fruit (parsley, carrots, anis, dill). Upon drying twin fruits break into two one-seeded segments called mericarps

29. Fruit and Seed Dispersal
Wind Dispersal
Small and Lightweight seeds.
Animal Dispersal
Seeds pass through digestive tract.
Fruits and seeds catch in fur or feathers.
Oils attract ants.
Water Dispersal
Some fruits contain trapped air.
Mechanical Ejection of Seeds

30. Seed dispersal

31. Pine Life Cycle

33. Seeds
Embryo shoot: Plumule
Embryo root: radicle

34. SEED GERMINATION (DICOTS)
Structure
Cotyledons - Food storage organs that function as first seed leaves.
Plumule - Embryo shoot.
Epicotyl - Stem above cotyledon.
Hypocotyl - Stem below attachment point.
Radicle - Stem tip developing into a root.
Ovule-ovary
attachment point

35. SEED GERMINATION (MONOCOTS)

36. Germination Germination is the beginning or resumption of seed growth.
Seed must be viable.
Some require a period of dormancy.To break the dormancy artificial techniques might be used such as:
Scarification: Reduce thickness of the coat
After Ripening: Remove inhibitors
Stratification: Cold requirement mimic
Favorable Environmental Factors
Imbibe water
Temperature: Above freezing but below 45
Light: Required in some (lettuce) but unwanted in others (California poppy)

37. Longevity
Viability of most seeds is significantly extended when the seeds are stored under conditions of low temperatures and kept dry.
Aquatic lotus-1000 years
Arctic tundra lupine years
Willow,orchids, cottonwood and tea-viable for only a few days
Cantoloupe, squash, cucumber- several years
Onion, leek- 2-3 years
Wheat with proper storage:30 years with 30 % viability
1879-William J. Beal- Experiment with 1000 seeds from 20 species of weeds
every 5 years, after 1920 every 10 years
In 1884 –most seeds of weeds germinated
In 1960-evening primrose, curly dock, moth mullein seeds germinated
In moth mullein, 1 mullein and 1 mallow seeds germinated
Six of original boxes are remaining and scheduled to be open in 2040
A few species produce seeds with no period of dormancy.
Vivipary

38. Rhizophora mangle (Vivipary)

39. Review
Dicots versus Monocots
Structure of Flowers
Fruits
Fleshy
Dry
Fruit and Seed Dispersal
Seeds
Germination
Longevity

40. Copyright © McGraw-Hill Companies Permission Required for Reproduction or Display

41. Oriental Sacred Lotus/ Nelumbo nucifera