The Story of Plants Flowers to Seeds & Back A gain! Matthaei Botanical Gardens and Nichols Arboretum, University of Michigan

Transcription

1 The Story of Plants Flowers to Seeds & Back A gain!

2 Let s start with pollination! Flowering plants produce flowers that when pollinated & fertilized make seeds. kidsgrowingstrong.org

3 Flowers have 5 major parts: p etal, sepal, stamen, pistil, & stem

4 Petals direct the pollinator to the flower. Sepals hold the petals. Stamens have anthers and filaments. Filaments hold the pollen. Pistils have a stigma, style and ovary. Fruits arise from a ripened ovary. Stems hold the flower upright, carry nutrients and hold the developing fruit on the plant /plants_and_ecology_notes.htm

5 Pollination: Pollen moves from anthers to stigmas. Fertilization: Pollen lands on the stigma, pollen tube develops and fertilizes the ovary at the base of the flower Seeds develop as the result of pollination & fertilization

6 Flowers come in many shapes and sizes, to attract different pollinators. Who might pollinate these flowers?

7 Flowers with flat faces are often pollinated by bees. The flat petals make A good perch for the bee while it drinks nectar Flowers that are white & fragrant at night may be pollinated by bats or moths Arboretum, University of Michigan

8 Tube shaped flowers are usually pollinated by butterflies, moths or hummingbirds. Male red oak flowers w/ new leaves Tree flowers may be wind or insect pollinated Male red maple flower Female red maple flower Arboretum, University of Michigan

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10 First a flower, then a fruit and inside the fruit are seeds! h/mcinto20.html

11 Seeds contain all the material necessary to grow into a new plant Seed parts have special names and special jobs to do: Coat, Endosperm, Embryo

12 Seeds can be found inside fruits or covered with a thin shell, like an acorn or a sunflower seed. Peaches are fleshy fruits with seeds covered by a hard case called an endocarp. PERICARP: The part of a fruit that surrounds the seed. The pericarp consists of the endocarp, mesocarp, and exocarp. ENDOCARP: The pericarp layer surrounding the seed. MESOCARP: The middle layer, usually fleshy. EXOCARP: The outer pericarp layer. It forms the skin of a grape or peach. Taken from MSU extension service

13 Why is it called a fruit? Fruits come in many different forms, and there are many different names for these fruits. But all fruits come from flowers & all fruits have seeds.

14 Flowering plants may be monocots or dicots. Both monocot and dicot seeds have endosperm; stored energy for the developing plant which is surrounded by the seed coat. Monocots, like corn, have 1 cotyledon, which stores energy for the growing plant, and develop a single first leaf within a sheath. Dicots, like beans, have 2 cotyledons for the growing plant and develop 2 first leaves. biology.unm.edu

15 Here are examples of a growing dicot (beans), and a growing monocot (corn). Notice that the dicot bean has 2 cotyledons and the monocot, corn has 1 cotyledon covered by a sheath.

16 Seed germination, beans vs. corn Beans are dicots and have 2 first leaves. Corn is a monocot and has 1 first leaf.

17 New plants may have two general types of roots Dandelions are dicots with tap roots. These grow from the seed part called the embryo radicle. Tap roots grows deep into the soil. Grasses are monocots with fibrous roots at the base of the stem. These do not have a single large root, but have many small roots.

18 As the plant develops, it grows a shoot. Shoots are above ground and include stems & buds

19 Rhizomes are special underground stems. Ginger is a kind of rhizome.

20 Leaves can be deciduous or evergreen. A leaf s job is to collect sunlight. From top to bottom:2- and 3- needle pines, spruce, fir, Douglas fir, cedar, larch.

21 Some evergreen leaves are flat and broad. Broadleaf evergreens live in warm climates. Rhododendron Banana Boxwood Bromeliad

22 And back to new seedlings where we start all over again!