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Home , Caltha, Gynoecium, Peduncle (botany)

1/29/20

Angiosperms Magnoliophyta - Flowering flowering plants Introduction to Angiosperms •"angio-" = vessel; so "angiosperm" means "vessel for the ” [seed encased in and later ]

• Dominant group of land plants and arose about 140 million years ago – Jurassic/Cretaceous

• 275,000+ species – diverse! Floral structure will be examined in lab next Mon/Tues – save space in your notes! • Co-evolved with animals and violet & fruit fungi

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Magnoliophyta - Flowering Plants Magnoliophyta - Flowering Plants

4 Features Define Angiosperms 2. Further reduction of the stages - 1. Possession of – with sac and grain and ovaries – ovary(ies) becomes a fruit

violet flower & fruit

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Magnoliophyta - Flowering Plants Magnoliophyta - Flowering Plants

2. Further reduction of the 3. : the 4. Vessel elements in xylem - gametophyte stages - embryo cell has two nuclei – efficient water conducting cells sac and pollen grain and ;

corn seed endosperm Cross section of young bean seed American basswood pink lady-slipper with cotyldeons- NO endosperm endosperm 5 6

Magnoliophyta - Flowering Plants The Flower

Classification of Angiosperms • The outstanding and most significant feature of the flowering plants is the flower Relationships of flowering plants • Understanding floral structure and names of are now well known based on the parts is important in recognizing, keying, DNA sequence evidence - APG and classifying species, genera, families. (Angiosperm Phylogeny Group) classification system is standard.

Changes in families (names and genera) have been common in recent years!

Field Manual of Michigan Flower: highy specialized = stem + has most up-to-date (generally) from Schleiden 1855

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The Flower The Flower

1. : floral stalk, the 4. : the second stem supporting the flower; of leaves, typically brightly sometimes referred to as the colored and and assist in attracting , collectively called the 2. : modified corolla [CO] floral stem or axis from which arise the floral appendages or modified leaves 5. : collective term for and [P]; 3. : the outer most whorl of leaves, typically if perianth parts cannot be differentiated into sepals green and protect the inner floral parts in ; and petals, that is, they look so much alike, then they collectively all sepals are called the calyx [CA] are called

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The Flower The Flower

6. Filament: slender stalk of 9. Ovary: basal portion of the supporting the pistil that contains ; at anther; permits exsertion of maturity becomes fruit with pollen out of flower seeds 10. Ovules: fertile portions 7. Anther: fertile portion of of pistil that contain stamen that dehisces to gametophyte (embryo sac); release pollen grains; develop into seeds after composed of anther sacs fertilization 8. Stamen: the male structure of flower comprising 13. Pistil: flask-shaped, female structure comprising three main filament and anther; collectively, all the stamens are parts; often referred to as carpel(s); all pistils (1 or more) are referred to as the androecium (= ‘house of males’) [A] referred to as the (= ‘house of ’) [G]

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The Flower The Flower

11. Style: slender stalk of pistil above ovary that the pollen tubes must pass What is the difference through to reach eggs in between the pistil and the ovules carpel? 12. : receptive portion at top of style that receives and recognizes pollen 13. Pistil: flask-shaped, female structure comprising three main 13. Pistil: flask-shaped, female structure comprising three main parts; often referred to as carpel(s); all pistils (1 or more) are parts; often referred to as carpel(s); all pistils (1 or more) are referred to as the gynoecium (= ‘house of females’) [G] referred to as the gynoecium (= ‘house of females’) [G]

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The Flower The Flower

• If 2 ‘leaves’ in one flower each separately form carpels,

• then the flower has 2 carpels and 2 pistils,

• gynoecium is 1 floral‘’in gynoecium Folded ‘leaf’ 1 carpel = 1 pistil apocarpic (separate carpels) palustris - Marsh marigold This gynoecium is monocarpic 9 (pistils) from 1 flower (one carpel) Gynoecium is apocarpic with 9 carpels or 9 pistils

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The Flower The Flower types- arrangement of ovules

Marginal - found in all monocarpic or apocarpic pistils

Axile - found in 3 floral ‘leaves’ in 3 carpels = 1 pistil 3 carpels = 1 pistil many syncarpic gynoecium fuse 3 styles 1 style pistils This gynoecium This gynoecium is syncarpic is syncarpic

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The Flower The Flower Placentation types- Numerical plan - usually referring to perianth arrangement of ovules Parietal - found in some syncarpic pistils

Free-central - perianth spiralled perianth 5-merous found in a few syncarpic pistils

Basal - found in some monocarpic, apocarpic, or syncarpic pistils perianth 4-merous perianth 3-merous

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The Flower The Flower

Symmetry Fusion

1. Connation: fusion Flowers radially of floral parts from symmetrical the same whorl Flowers actinomorphic Fusion of carpels Syncarpic pistil

Flowers bilaterally symmetrical Flowers zygomorphic Fusion of Corolla tube Fusion of stamens Staminal tube petals

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The Flower The Flower Floral formulas 2. Adnation: fusion of floral Fusion parts from different whorls

4 sepals (CAlyx) 4 petals (COrolla) 8 stamens (Androecium) 4 carpels (Gynoecium)

Oenothera biennis Evening primrose

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The Flower The Flower Floral formulas Floral formulas

4 sepals (CAlyx) 4 sepals (CAlyx) 4 petals (COrolla) 4 petals (COrolla) 8 stamens (Androecium) 8 stamens (Androecium) 4 carpels (Gynoecium) 4 carpels (Gynoecium) Carpels fused = 1 pistil Carpels fused = 1 pistil Ovary inferior

Oenothera biennis Oenothera biennis Evening primrose Evening primrose

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The Flower Floral formulas

4 sepals (CAlyx) 4 petals (COrolla) 8 stamens (Androecium) 4 carpels (Gynoecium) Carpels fused = 1 pistil Ovary inferior (+ hypanthium tube) Oenothera biennis Evening primrose

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