# Science: An Elementary Teacher’s Guide/Plants

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## Parts of a Plant

* Seeds
* Roots
* Stems
* Leaves
* Flower
Each part of a plant has a very important function.
Plant Parts
* Stems
-Have little tubes that carry water and food to the rest of the plant
-Hold up leaves and flowers of the plant
-Grass, flowers, and vines have soft stems
* Roots
-Collect water and minerals for the plant
-They hold the plant in the ground
-Some plants store food in the roots
* Leaves
-Make food for the plant
-Green leaves + air + sunlight = plant food
* Flowers
-Flowers are many sizes, colors, and shapes
-Make seeds
-The seeds grow into new plants

### Seeds
## Summary

A seed is produced in the flowering plant by the fruit. Some plants have one seed while others have many seeds. The seed can then grow into a new plant, just like the one that produced it.
A seed has three parts; the seed coat, the embryo, and an area of stored food. The seed coat protects the seed with a hard covering. The embryo is the new plant inside the seed with growing capabilities for the new flowering plant. The stored food gives the seed and the plant within it nutrients until the plant grows with leaves and can produce food for itself. Some seeds are spread by wind blowing them like dandelions, others by animals like raccoons eating berries then leaving droppings, people also spread them think about when you walk through tall grass we get burrs and seeds on our clothing and when we dust it off we spread the seeds around. Humans have a great use for the seeds of plants, we eat them. Humans eat seeds such as oats, peas, beans, and various types of nuts. We use the peanut oil and cottonseed oil from seeds for cooking as well as pepper and nutmeg for spices. Seeds are also used for medicine anise and flax seed are used to cure colds and cholesterol.
Seeds contain new plants
* A seed is the start of a new plant
* The have different shapes, sizes and colors
* Flowers make seeds
* Covered in a seed coat to protect and keeps tiny leaves and root inside
* Contains food for the new plant
* seeds travel
-seeds stick to socks -stick to animal fur -seeds blow in the wind
* seeds to grow need:
-Soil -Water -Sunlight -Seeds are planted to grow in the gardens

## Uses of Plants

Plants have different uses and along the way people where able to discover a variety of uses for them either it was for food, medicine, and clothing. Plants make oxygen. One of the materials that plants produce as they make food is oxygen gas. This oxygen gas, which is an important part of the air, is the gas that plants and animals must have in order to stay alive. When people breathe, it is the oxygen that we take out of the air to keep our cells and bodies alive. So basically we as people could not survive with out plants mainly because we use them for oxygen with out them we would be dead. Some examples of the use of plants are:

## Plant Stages

* Stage 1
Germ grows inside seed
* Stage 2
Plant shoots up from germ Roots develop down from germ
* Stage 3
Leaves develop Roots grow
* Stage 4
Flower buds grow
* Stage 5
Full-grown plant Leaves, stems, flowers and roots

### Roots

The root system of a plant constantly provides the stems and leaves with water and dissolved minerals. In order to accomplish this the roots must grow into new regions of the soil. The growth and metabolism of the plant root system is supported by the process of photosynthesis occurring in the leaves. Photosynthate from the leaves is transported via the phloem to the root system. Root structure aids in this process. This section will review the different kinds of root systems an look at some specialized roots, as well as describe the anatomy of the roots in monocots and dicots.
As weird and gross as it may sound, humans actually eat roots of plants. We eat roots such as carrots, radishes, beets, and turnips. Some roots, licorice for example, is used in making teas, candies, and medicines.
Adventitious roots arise out-of-sequence from the more usual root formation of branches of a primary root, and instead originate from the stem, branches, leaves, or old woody roots. They commonly occur in monocots and pteridophytes, but also in many dicots, such as clover (Trifolium), ivy (Hedera), strawberry (Fragaria) and willow (Salix). Most aerial roots and stilt roots are adventitious. In some conifers adventitious roots can form the largest part of the root system.
Aerating roots (or knee root or knee or pneumatophores or Cypress knee): roots rising above the ground, especially above water such as in some mangrove genera (Avicennia, Sonneratia). In some plants like Avicennia the erect roots have a large number of breathing pores for exchange of gases.
Aerial roots: roots entirely above the ground, such as in ivy (Hedera) or in epiphytic orchids. Many aerial roots, are used to receive water and nutrient intake directly from the air - from fogs, dew or humidity in the air.[11] Some rely on leaf systems to gather rain or humidity and even store it in scales or pockets. Other aerial roots, such as mangrove aerial roots, are used for aeration and not for water absorption. Other aerial roots are used mainly for structure, functioning as prop roots, as in maize or anchor roots or as the trunk in strangler fig. In some Epiphytes - plants living above the surface on other plants, aerial roots serve for reaching to water sources or reaching the surface, and then functioning as regular surface roots.
Contractile roots:they pull bulbs or corms of monocots, such as hyacinth and lily, and some taproots, such as dandelion, deeper in the soil through expanding radially and contracting longitudinally. They have a wrinkled surface.
Coarse roots: Roots that have undergone secondary thickening and have a woody structure. These roots have some ability to absorb water and nutrients, but their main function is transport and to provide a structure to connect the smaller diameter, fine roots to the rest of the plant.
Fine roots: Primary roots usually <2 mm diameter that have the function of water and nutrient uptake. They are often heavily branched and support mycorrhizas. These roots may be short lived, but are replaced by the plant in an ongoing process of root 'turnover'.
Haustorial roots: roots of parasitic plants that can absorb water and nutrients from another plant, such as in mistletoe (Viscum album) and dodder.
Propagative roots: roots that form adventitious buds that develop into aboveground shoots, termed suckers, which form new plants, as in Canada thistle, cherry and many others.
Proteoid roots or cluster roots: dense clusters of rootlets of limited growth that develop under low phosphate or low iron conditions in Proteaceae and some plants from the following families Betulaceae, Casuarinaceae, Elaeagnaceae, Moraceae, Fabaceae and Myricaceae.
Stilt roots: these are adventitious support roots, common among mangroves. They grow down from lateral branches, branching in the soil.
Geotropism: natural tendency for root to grow down against the force of gravity.
Storage roots: these roots are modified for storage of food or water, such as carrots and beets. They include some taproots and tuberous roots.
Structural roots: large roots that have undergone considerable secondary thickening and provide mechanical support to woody plants and trees.
Surface roots: These proliferate close below the soil surface, exploiting water and easily available nutrients. Where conditions are close to optimum in the surface layers of soil, the growth of surface roots is encouraged and they commonly become the dominant roots.
Tuberous roots: A portion of a root swells for food or water storage, e.g. sweet potato. A type of storage root distinct from taproot.

### Leaves

The main function of the Leave is to produce food and discharge waste. Leaves are the parts of the plant where food is produced by the process called photosynthesis. Photosynthesis is the process in which leaves take sunlight and water to produce food(sugar). Leaves take in carbon dioxide from the air and converts the carbon dioxide into oxygen.
Leaves are essential for humans and other mammals. Leaves are used for medicine,food, fuel, shelter and even clothing. Some beverages are produced by different process that the tea leaves are treated. White, green, black, Oolong and matcha are the most common teas produced using tea leaves . Leaves are also used as beauty product such as hair dyes and henna which is made of different types of plants mash together to make a paste; A paste used to decorate skin. In tropical areas humans will use large leaves, like palm leaves, as shelter to cover and make a roof for their homes. Leaves are also greatly used as a food source such as lettuce, cabbage, parsley, spinach, tea, and tobacco for recreational drug. Human would perish without plants.
Autumn Leaves Colors
Why do leaves change color in fall? The leaves are green during growing season because of the presence of the chlorophyll pigment. When the leaves end the growing season the true color of the leaves start to appear. As the days start to become shorter in fall season the leaves shut down the production of chlorophyll and the "true" colors of the leaves appear such as red, orange and yellow. Even when the leave changes color it does not mean it is dead. When The winter hits the cold will kill the leaves changing the color to brown.
The structure of a Leaf
The leaves are the organ for photosynthesis. It is where photosynthesis takes place. The structures of leaves are adapted for efficient photosynthesis.
* Large surface area Most leaves are broad and have a large surface area allowing them to absorb more light.
* A thin shape A thin shape means a short distance for carbon dioxide to diffuse in and oxygen to diffuse out easily.
* Chlorophyll This chemical gives the leaves their green colour and transfers light energy to chemical energy.
* Veins Networks of veins support the structure of the leaf and transport substances to and from the cells in the leaf.
* Stomata These are small holes on the underside of the leaf that allow gases to diffuse in and out.

## Pigments

Plants produce a greater variety of pigments, more than what animals produce. There are four types of pigments. The pigments are part of the photosynthesis. The production of the pigments depends on the color the leaves will get before falling in fall. Chlorophyll is the pigment of photosynthesis. Example in Sunflowers, when chlorophyll pigments stop production the yellow and orange colors become visible.
Chlorophyll = green leaves
Carotenoids = oranges
Anthocyanins = purples and reds
Xanthophyis = yellow

### Flowers

These are the reproductive parts of a plant. All plants produce flowers for the same reason: to make seeds so another plant can grow. Flower petals and the flower's smell attract insects (bees, beetles, butterflies, etc) to pollinate the flower (the plant rewards the pollinator with nectar). After pollination, the petals fall off and seeds develop in the part of a flower called the ovary. The ovary itself usually becomes what we call the fruit.
For humans flowers serve more as a want you can say than a need. We use flowers when we want to brighten up our homes or decorate an event to make it look beautiful. We also take flowers though for a scent. Many flowers are used in making perfumes lotions, and soaps.
Parts of a Flower
Flowers have four parts: sepals, petals, pistil, and stamens. A complete flower has to have all this parts. A flower that lacks one or more of these parts is called an incomplete flower.
* Sepals
They are the leaf-like, usually green structures at the flower base. They function to protect the flower as it's forming.
* Petals
These are the colorful parts of the flower that function to attract pollinators. There are different petal colors, and they can attract different types of animals and insects to act as pollinators.
* Stamens
They are the male reproductive parts of a flower. The tube is called the filament, and the ball on top is called the anther. The anther produces pollen grains, which contain the flower's sperm. When pollinators come into contact with the anther, they may carry pollen grains away to fertilize a flower.
* Pistil
This is the female reproductive parts of the flower. A pistil is often bottle-shaped, and it has three main parts: the stigma, style and ovary.

### Stems

The Stem supports the upper parts of plants and transport water and dissolved nutrients from the soil up the stem in a system of tubes. Food from the leaves travel down stems to the roots. Stems can also store food for the plant.The stem transports water and nutrients through tiny tubes that are in the stem from the soilto be disturbed to the leaves, and they carry food manufactured by the leaves to the roots to the leaves for photosynthesis to occur.Water then comes up to the stem though the tiny tubes of the tissue called ''''''Xylem''' .Xylem is the vascular tissue in plants that conducts water and dissolved nutrients upward from the root and also helps to form the woody element in the stem. This process begins at the roots, where water is absorbed and moved from cell to cell by osmosis. 'Osmosis (is the natural tendency of cells to maintain an equal concentration of water on both sides of the cell wall. Because of osmosis, the movement of water goes into the roots and creates a mild pressure called root pressure. ‘Transpiration than occurs which evaporates the water through the stomata of the leaves, moving the water up to the stem. The energy of the heat then causes the water to move into the leaves creating a water shortage in the upper cells. This causes water to move into the leaves from the cells below. The upward movement of the water through the plant is called 'Transitional Pull'''Italic text. Food that is produced in the leaves are also transported by the tubes in the stem to the roots.'
Stems of a plant have several function. The stem helps to propagate several plants such as plumeria, magnolia, roses and fig plant. Stem is also used as a transportation of nutrients from roots to upper part of the plant and from leaves to the roots. Stems of a plant can have many uses to humans such as a food and medicine. Clothing made from fibers of the stems of hemp and flax, and stems of trees being used as shelter, furniture, or for fires.
* The nodes hold one or more leaves, as well as buds which can grow into branches.
* The internodes distance one node from another.
Stems have four main functions which are: • Support for and the elevation of leaves, flowers and fruits. The stems keep the leaves in the light and provide a place for the plant to keep its flowers and fruits. • Transport of fluids between the roots and the shoots in the xylem and phloem. The phloem, carries sugar to all parts of the tree, including the roots. • Storage of nutrients • Production of new living tissue. The normal lifespan of plant cells is one to three years. Stems have cells called meristem that annually generate new living tissue.

### Some major Groups of Plants

* The Simple Plants - (first division-phylum) live in most areas of the world, from the tropics to the polar regions, but they are always in areas where there is liquid water at some time of the year, as water is necessary in their reproductive process.
* The Vascular Plants - ( second division) have a vascular system which consists of tiny tubelike structures that transport waster and nutrients from soil to various parts of the plant.
* Evergreen Plants (Conifers) - cone-bearing plants. Known for evergreens including redwood, spruce, fir, cedar, and pine. used for lumber, and some for making paper.
* Deciduous Plants - drop their leaves in autumn and go into a period of time of dormancy for the winter.
* Flowering Plants - The main parts of flowering plants are seeds, roots, stems, leaves, and flowers. Form fruits that contain seeds.
All plants belong to the Kingdom Plantae.

### Reproduction in Plants

Parts of a Female Flower The pistil is the female part of the flower. Its parts include a style with a sticky top called the stigma and an ovary. In the ovary are ovules which has an egg nucleus that when fertilized becomes the embryo (seed).
Parts of a Male Flower The stamen is the male part of the flower. The stamen can be found inside the petals around the pistil. Stamens contain filament and anther. Anther is what produces the pollen. Each pollen grain contains an sperm nucleus that can fertilize and egg nucleus.
A pollen grain will attach itself to the sticky stigma, a tube begins to grow down thorough the pistil, preparing a passage for the sperm nucleus to make its way to the ovary. It then enters the ovule and joins with the egg. when the egg inside the ovule is fertilized the seed begins to form. An egg however, no matter how it is pollinated, can only be fertilized by the same plant.
Reproduction
There are 4 organs that help the reproduction. When a plant has the four parts it is called a complete flower. If one of this parts is missing it is a Incomplete flower. In order for reproduction to occur pollen in the anther need to be insert to the stigma. The stigma then will transport the pollen to the ovary or ovule.
Pollination
Two types of pollination are self-pollination and cross-pollination. Self-pollination is when pollen comes from the same flower or type of flower. Pollen of the same flower is use for reproduction. Cross-pollination is when pollen comes from a different flower. Cross-pollination is done by vary of factors such as:
animals passing through the plants dropping and picking pollen with their fur as they walk through the plants
insects attracted by the nectar and vibrant colors of the flowers
rain, wind and other natural factors

## Asexual Reproduction

Plants that can be propagate without the need of a seed are known to go under asexual reproduction. Plants can be propagate by cuttings or drafting. Asexual reproduction allows the plants to pass on the good traits. Plants will keep same traits as parents plants; new plants are known as clones( this plants are genetically identical to parent plant) . Pieces of the stem or leafs planted are an easy way to propagate plants.
$^{Exampleofstempropagationare:}$
Roses by cutting a large piece of stem in a diagonally cut and placed in water or soil will all the plant to grow roots. The rose will keep the identical traits of the parent flower allowing the rose to pass on the good features. Jasmine, plumeria and magnolia are another example of plants that can be propagated by cutting stem.
$^{Exampleofleafpropagationare:}$
ZZ plants is a plant that can easily be propagate by cutting the leaf and dig down the soil where the base of the leaf can absorb the water and nutrients of the soil.

## Plants can reproduce without seeds

This process is called "asexual reproduction"
* Cuttings
Begonias, coleus, and many other plants can reproduce from cuttings, and the process can be simple as placing a piece of stem( with leaves on it) in water or moist sand or soil. In a few days, roots begin to grow at the base of the leaf and a new plant develops.
* Stems and Bulbs
Bulbs, will begin to grow and form new plants when placed in proper conditions of moisture and temperature. Examples: When potatoes have underground stem tips, called tubers. Tubers contain stored food and, with proper moisture and temperature, can grow into new plants. Potatoes can produce as long as it has one bud. The bud is where new growth occurs.

## Photosynthesis

Photosynthesis is the process by which plants convert sunlight into energy. Basically combining carbon dioxide and water in the presence of light energy (glucose). Plants obtain sunlight from sun, water from soil, carbon dioxide from air. The plant uses all this to make their food. nutrients from root to the leaves and leaves to roots are transport thru the stem from a tube called xylem. The process of making food occur in the leaves and extra glucose is stored on the roots and will be used to produce photosynthesis when there is a lack of sunlight. Even when plants discharge waste as oxygen, some oxygen is needed for the photosynthesis occurs. The balance of gasses is controlled by the small pores in the leaves called stomata. Oxygen comes out of the stomata and allows carbon dioxide to come inside the plant.
Most plants need photosynthesis to grow. Plants that do not need photosynthesis to growth such as mushrooms obtains its food from the ground.

## Quiz

Show your knowledge about plants (Click on the letter of the correct answer.)

## Vascular Plants

Second division of the plant kingdom is Tracheophyta in this division have vascular system which consists of tiny tubelike structures that transport water and nutrients from soil to various parts of the plant. The trees, shrubs, flowers, and grasses nearly all of the organisms that most of us think of as plants are tracheophytes.

## Evergreen Plants

Are also called conifers is cone-bearing plants scaly cones which contain seeds. Conifers are recognized for their soft wood and for the production of a sticky substance resin. Evergreen include redwood, spruce, fir , cedar, and pine.

## Needles and Scales

Leaves of conifers are either needles or flat scales it stay on the plant through the winter is the reason these plants are evergreens. Cedars and junipers have a scalelike leaves pine, spruce, and fir have leaves that are long thin needles. The pine needles are pointed and are arranged in bundles or packages of one, two, and eight. The spruce needles are sharp and separate or single on the twig and the fir tree needles are flexible and flat.

## Deciduous Plants

Trees that drop their leaves in the autumn and go into a period of dormancy for the winter.

## Transpiration

When water brought up from the roots is used in making food excess water must be allowed to leave the plant. Taking in carbon dioxide and releasing oxygen into the air the stomata also provide a system to control the amount of water in the plant. The stomata are kept wide open so that as much carbon dioxide as is needed can enter the plant. When the water supply to the roots is limited or the plant is losing water too rapidly the guard cells will narrow or close the stomatal openings in conserving the water.

## Color Changes in Leaves

At the time of the growing season these colors are hidden by the green color of chlorophyll and when the plant comes to the end of its growing season and stops producing chlorophyll the hidden colors appear.

## Simple Plants

Plants are mostly small their are mosses and liverworts. Few bryophytes are more than 2 centimeters in length. They live in most areas of the world from the topics to the polar regions they are always in areas where there is liquid water at some time of the year as water is necessary in their reproductive process.

## Vascular Plants

Tracheophyta plants in this division have a vascular system consists of tiny structures that transport water and nutrients from soil to various parts of the plant.
Any of various plants that have the vascular tissues xylem and phloem. The vascular plants include all seed-bearing plants (the gymnosperm sand angiosperms) and the pteridophytes (including the ferns, lycophytes, and horsetails). Also called trichophytes. Compare nonvascular plant.

## Evergreen Plants

Conifers are recognized for their soft wood and for the production of a sticky substance that is resin. Evergreens include redwood,spruce,fir,and pine.

## Deciduous Plants

Trees that drop their leaves in the autumn and go into a period of dormancy for the winter.

## Flowering Plants

Forms fruits that contain seeds. Roses,gardenias, and orchids lose their leaves in the fall as maples, elms, and fruit trees.
Flowering plants (angiosperms), also known as Angiosperm or Magnoliophyte, are the most diverse group of land plant, with 416 families. Like gymnosperms angiosperms are seed- producing plants; they are distinguished from gymnosperms by characteristics including flowers, Endosperm within the seeds, and the production of fruits that contain the seeds. Etymologically, angiosperm means a plant that produces seeds within an enclosure, in other words, a fruiting plant.