1. Chapter 8 Lecture Outline Flowers, Fruits, and Seeds Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.

2. Outline  Introduction-- Reproductive Organs  Phylum Anthophyta-- Differences Between Eudicots and Monocots  Structure of Flowers  Fruits  Fruit and Seed Dispersal  Seeds

3. INTRODUCTION--REPRODUCTIVE ORGANS  Sexual Reproduction  Primitive Reproductive Organs Archegonia Antheridia Sporangia  Complex Reproductive Organs of the Higher Plants Cones Flowers of Angiosperms

4. PHYLUM ANTHOPHYTA--Eudicots and Monocots DicotsMonocots Two cotyledonsOne cotyledon Flower parts in multiples of four or five Flower parts in multiples of three Leaves with distinct network of veins Leaves with parallel primary veins Vascular cambium and cork cambium present Vascular cambium and cork cambium absent Vascular bundles of stem in ringVascular bundles of stem scattered Pollen grains with three apertures Pollen grains with one aperture  Two major classes of flowering plants: Eudicots (Magnoliopsida) and Monocots (Liliopsida)

5. Structure of Flowers  Flowers begin as embryonic primordium PARTS  Peduncles. pedicels  Receptacle - Swollen end of peduncle or pedicel Other parts of flower attached to receptacle in whorls: sepals, petals, stamens, and pistil.

6. Structure of Flowers  Sepals - Outermost whorl calyx function  Petals - Next whorl inside sepals corolla – Function of Showy corollas: – Inconspicuous or missing corollas in plants that are: Calyx and corolla form perianth.

7.  Stamens attached around base of pistil. filament anther – Pollen grains developed in anthers.  Pistil = female portion: Ovary: – Ovules Style: Stigma:

8. OVARY … – Superior Ovary – – Inferior Ovary – Ovary with ovules. o Seeds develop from: o Fruit develops from: – Simple or Compound Ovary:

9. Inferior Ovary …

10. Structure of Flowers  Flowers can be produced singly or in inflorescences. Inflorescence – Spike: – Raceme: – Panicle: – Umbel: – Compound Umbel: – Head: – Catkin:

12. Fruits  Fruit = develops from: And from Accessory parts:  Phylum of Plants w/ fruits: Tomato fruit

13. Fruit Anatomy  Pericarp: Three regions collectively  Fruit Regions Exocarp: Endocarp: Mesocarp: Peach fruit

14.  Variability of fruits fleshy or dry Formed from one or more flowers Milkweed follicle

15. Types of Fruits  Fleshy Fruits: SIMPLE FLESHY FRUITS: # PISTILS – Drupe: single seed enclosed by hard, stony endocarp (pit) Drupes: peaches, almonds, olives

16. Simple fleshy fruits … – Berry – Pericarp: __________ – Ovary: ______________ – # seeds _______ – True berry - thin skin and soft o Examples: – Pepo - Relatively thick rind o Examples – Hesperidium – leathery skin has citric acid glands o Examples Grape berries

17. – Pome - receptacle grows: o Endocarp papery or leathery o Apples, pears Apple pomes Berry – Hesperidium - Leathery skin containing oils o Citrus

18. Fruits  Complex Fleshy Fruits Aggregate Fruits – Derived from single flower with several to many pistils Multiple Fruits - several to many individual flowers in single inflorescence – Mulberries, Osage orange, pineapples, figs o Examples Blackberry aggregate fruits Osage orange multiple fruit

19. Fruits  Dry Fruits - Mesocarp dry at maturity Dehisicent or indehiscent DEHISCENT FRUITS Follicle - Splits along one side – Larkspur, milkweed, peony Legume - Splits along two sides – Legume family: peas, beans, lentils, peanuts Milkweed follicle Legumes

20. Fruits  Dehiscent fruits … Siliques: More than three times longer than wide Examples: Silicle Silique

21. Fruits  Dehiscent fruits … Capsules – split in: Examples: Capsules

22. Fruits  Dry Fruits  INDEHISCENT FRUITS = Single seed: united with pericarp – Achene - Base of seed attached to pericarp. o Examples – Nut - harder and thicker pericarp with: o Examples: Inside of sunflower achene Acorn

23. Fruits  Indehiscent Fruits Grain (Caryopsis) - Pericarp tightly united with seed – Examples: Samara - Pericarp extends as: – Examples: Schizocarp - Twin fruit Examples Corn section Samaras Schizocarp of mericarps

24.  FLESHY Simple Aggregate Multiple DRY – Dehiscent – Indehiscent

25. Fruit and Seed Dispersal  Dispersal by Wind Fruits and/or seeds have:

26. Fruit and Seed Dispersal  Dispersal by Animals 2 Main Types –

27. Dispersal by Animals … Oils attract ants. – Elaiosomes on bleeding hearts used as food by ants. Seeds from bleeding hearts. Elaiosome is white.

28.  Water Dispersal Some fruits contain trapped air for floatation.

29. Seeds  Structure Ovules develop into seeds. – Cotyledons - Food storage organs that function as “seed leaves” – Embryo = cotyledons and plantlet Bean seed

30. Germination  Germination = Fruit Ripe when – after embryo develops.

31. Germination …  Favorable environmental factors needed for germination. W O L T  Enzymes activated by:

32. Germination Some require period of dormancy. – Period of Cold – Mechanical Abrasion o Scarification: – Growth-inhibiting substances present in seed coat or fruit– that must be washed off by rain

33. Longevity  Seed viability varies, depending on species and storage conditions. Viability extended: – Temperatures – Wet or Dry?