Matthaei Botanical Gardens and Nichols Arboretum, University of Michigan

The Story of Flowering Plants: flowers, fruits and seeds and seedlings

kidsgrowingstrong.org

And now; SEEDS and PLANT PARTS for 2nd & 3rd graders !

When flowers are pollinated & fertilized they make seeds.

F l o w e r s h a v e 5 m a j o r p a r t s : Pe t a l , S e p a l , S t a m e n , P i s t i l , & S t e m

May also be called a carpel

Matthaei Botanical Gardens and Nichols Arboretum, University of Michigan

Pollination: Pollen moves from the anthers to the stigma. Fertilization: Pollen lands on the stigma, a pollen tube develops and fertilizes the ovary at the base of the flower Seeds: The result of pollination and fertilization. Also called ovules found in the ovary.

Pollination and Fertilization Make Seeds

Flower power! Important to pollination: Petals Attracts the pollinator to the flower. Sepals Hold the petals and also cover the young developing bud before the flower blooms. Stamens Male part of the flower, composed of anthers and filaments. Pollen Is found on the filament Pistil (also called a carpel) has a stigma, style and ovary. It is the female part of a flower. Fruits arise from a ripened ovary. Ovary holds ovules which will become seeds. A fertilized ovary changes into a fruit. Stems hold the flower upright, carry nutrients and hold the developing fruit on the plant.

http://www.bb.iastate.edu/necgex/Flowers.htm

Flower parts and their roles

See the seeds developing in the flower ovary?

Flowers come in many shapes and

sizes, to attract different

pollinators.

Guess who might pollinate these flowers?

Matthaei Botanical Gardens and Nichols Arboretum, University of Michigan

Matthaei Botanical Gardens and Nichols Arboretum, University of Michigan

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

Tube shaped flowers are usually pollinated by butterflies, moths or

hummingbirds.

Tree flowers may be wind or insect pollinated

Matthaei Botanical Gardens and Nichols Arboretum, University of Michigan

Examples of pollinators and preferred flowers

Flowers may produce different types of fruits & seeds

Simple fruit. A simple fruit develops from a single carpel (or several fused carpels) of one flower (examples: lemon, peanut, banana).

Aggregate fruit. An aggregate fruit develops from many separate carpels of one flower (examples: raspberry, blackberry, strawberry).

Multiple fruit. A multiple fruit develops from carpels of many flowers (examples: pineapple, mulberry, osage-orange).

Accessory fruit. An accessory fruit contains other floral parts (such as the receptacle) in addition to ovaries ( examples: apple, strawberry).

Matthaei Botanical Gardens and Nichols Arboretum, University of Michigan

http://evolution.berkeley.edu/evolibrary/home.php

Flowers may be pollinated by more than one thing: wind, bird, or insect.

But most pollinators prefer a specific type of flower, and most flowers have a best way to be pollinated

Now that we understand pollination of flowers, let’s look at seeds!

Remember: First a flower, then a fruit and inside the fruit are seeds!

http://www.botany.org/bsa/misc/mcintosh/mcinto20.html

Matthaei Botanical Gardens and Nichols Arboretum, University of Michigan

Pericarp: ‘Peri-’ means around, the pericarp is made of the endocarp, mesocarp, and exocarp. The pericarp surrounds the seed. Endocarp: ‘Endo’ means inside. This thin layer surrounds and protects the seed. Mesocarp: ‘Meso’ means middle. This middle layer, is between the exocarp and the endocarp. Exocarp: ‘Exo’ means out. This outer layer holds the fruit together. It forms the skin of a grape or peach.

Image from MSU extension service http://www.extension.org/pages/55717/exocarp

So, what’s a fruit? Fruits have seeds inside. They might be fleshy, like a peach or dry, like a nut. They develop from a fertilized flower. The ovary wall swells and creates layers surrounding the seed. Fruits have a pericarp that surrounds the seed..

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. The fruit comes from the ovary wall. The seeds are the fertilized ovules.

How many different fruits ?

Matthaei Botanical Gardens and Nichols Arboretum, University of Michigan

Let’s look inside the fruit to find the Seeds! NATURE’S NEW PLANT PACKAGE

Seeds have everything the plant needs to make a new plant. Most seeds have a seed coat, endosperm and embryo and a cotyledon.

Seed coats protect the seed. Endosperm stores nutrients.

The embryo is the baby plant. The cotyledon is part of the developing seed.

When the seed takes on water and germinates, the cotyledons swell, a root radicle emerges and a shoot develops.

Scientist divide plants into monocots or dicots based on number of cotyledons. Monocotyledons have one first leaf and one cotyledon. Also called a monocot.

Dicotyledons have two first leaves and two cotyledons. Also called a dicot.

Corn is an example of a monocot. Beans are an example of a dicot.

C o r n - a m o n o c o t a n d B e a n s - a d i c o t . 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 also stores some energy for the growing

plant, and develops a single first leaf within a sheath. Dicots, like beans, have 2 cotyledons for the growing plant and develops 2 first leaves.

In both cases, when the leaves grow above ground they can start photosynthesis. Plants

make food through photosynthesis.

biology.unm.edu

What is the name of the food storage part of a seed? What part sprouts from the growing seed first? Root or shoot? Corn is a monocot, beans are dicots. How many first leaves will a corn seedling have? How many first leaves will a bean sprout have? What part of the flower does the seed come from?

Let’s go back to monocot and dicot seeds for a quick review.

You’re almost a plant expert! Let’s move to other important parts of a plant.

Roots: tap roots and fibrous roots anchor plants

and absorb minerals and water.

Stems: shoots hold the plant upright, and conduct water and nutrients up and down the

plant.

Leaves: come in many shapes and sizes and make food for the plant through

photosynthesis.

P la n t s u s u a l l y h a v e t w o t y p e s o f r o o t s

Dandelions are dicots with tap roots. Remember the root radicle part of the seed? This grows into more roots. Tap roots grows deep into the soil to anchor the plant and absorb water.

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. Fibrous roots spread out to capture water near the surface of the soil.

A s t h e s e e d g r o w s , i t d e v e l o p s a s h o o t . S h o o t s g r o w a b o v e g r o u n d a n d b e c o m e s t e m s

& b u d s . A s t e m c a n b e h a r d a n d w o o d y o r s o f t a n d h e r b a c e o u s .

S t e m s h o l d p l a n t u p r i g h t t o r e a c h t h e s u n . S t e m s m a y h a v e b u d s . B u d s m a y c o n t a i n b a b y l e a v e s , s o m e b u d s c o n t a i n b a b y f l o w e r s .

This picture shows a tomato plant from root tip to shoot tip. Look for all the parts of the plant. Can you find them all?

S o m e s t e m s g r o w u n d e r o r a l o n g t h e g r o u n d . T h e s e a r e c a l l e d r h i z o m e s a n d a r e

s p e c i a l u n d e r g r o u n d s t e m s . G i n g e r i s a k i n d o f r h i z o m e .

L e a v e s a r e a n i m p o r t a n t p l a n t p a r t . A l e a f ’s j o b i s t o c o l l e c t s u n l i g h t . T h e y c a n b e d e c i d u o u s o r e v e r g r e e n .

H e r e a r e p i c t u r e s o f l e a v e s f o u n d i n M i c h i g a n .

From top to bottom: pines, spruce, fir, Douglas fir, cedar, larch.

S o m e e v e r g r e e n l e a v e s a r e f l a t a n d b r o a d . T h e s e e v e r g r e e n s p r e f e r t o l i v e i n w a r m c l i m a t e s , o r h a v e w a x y c o v e r i n g s t o k e e p t h e m f r o m d r y i n g o u t i n t h e

w i n t e r. B u t t h e i r m a i n j o b t o c a p t u r e s u n l i g h t .

Rhododendron

Boxwood Bromeliad

Banana

Matthaei Botanical Gardens and Nichols Arboretum, University of Michigan

Now that you now are a plant expert, let’s explore seeds, fruits

and twigs up close!