BIOLOGY Unit 1 | Botany Chapter 1 | The Flowering Seed Plants Biology - Defined as study of living things - Bio- means life - -logy means study of - When you see a field of plants and animals, a mountain stream, or an ocean you are looking at how Biology began. - Throughout this year we will study many of the organisms (living things) that God created and their habitats (regions where particular organisms live). Major Fields of Biology - Botany - Study of plants - Zoology - Study of animals - Human Anatomy and Physiology - Study of the physical structure (anatomy) and function (physiology) of the human body Importance of Botany - All food comes directly or indirectly from green plants. Whether the food is the plant or the animal we eat has eaten the plant. - Plants are also used for drugs and antibiotics in medicine. - Plants are vital in industry for lumber, paper, and clothing. Review 1. Explain the origin of the word biology. 2. What are the three major fields of biology? 3. Name three reasons why the study of botany is important. Collecting & Observing Plants - Study of Botany begins with the collection and observation of plants and plant organs. - Most green plants possess roots, stems, leaves, flowers, & fruits. Flowers - Note color, type, and arrangement of flowers. Flowers are very important to plants. - Flowers help plants to reproduce. - Reproductive cells in the flowers unite to form embryos. Embryos are located within the seeds, which are in the fruit. Under the right conditions, the embryo in the seeds will develop into a mature plant. - Most plants with flowers will produce fruits and seeds. You may notice these when observing a plant that has lost its flowers. Leaves - Note the shape, size, arrangement and number. - Leaves are vital to plants because most of the plant's food is manufactured in the leaves through photosynthesis. Stems - Note the appearance and feel of stems. - Leaves and flowers are held up by the stem, which also transports substances and stores food. - Land plants are classified as either trees, shrubs, herbs, or vines. Woody Plants - Tree is a plant with a single tall, woody stem capable of standing without support. - Shrub is a plant with several low, woody stems near the ground. Nonwoody Plants - Herbaceous plants or herbs has a relatively soft stem. - Herbs are used for medicine, seasoning, and flavoring. The fourth kind of plant, the vine, can be woody or nonwoody. A vine grows along the ground or has tendrils that twine around a wall for support. Roots - Anchors the plant to the soil and absorbs water and minerals and stores food. Taproot System - Main root that grows straight down and is bigger than the secondary roots that branch off storing large amounts of food. Fibrous Root System - The primary root remains small, and many slender secondary roots grow from it in all directions. The tangled mass serves to hold soil particles together and prevent soil erosion. Review 1. Why are flowers important to plants? 2. How is the scientific definition of herb different from its everyday meaning? 3. How are taproot systems different from fibrous root systems? Common Plants - About half of the plants known to man are angiosperms (whose flowers produce seeds covered by fruit.) - All flowering plants, including broadleaf trees, grasses, garden flowers, weeds, and vegetables, are angiosperms. - There are about 140 families of angiosperms, which are further divided into 250,000 species. The Composite Family Disks and Rays - One of the largest families of angiosperms is the composite family, also called the sunflower family. - These flowers superficially resemble a single flower, but each is a cluster of many separate flowers referred to as a head. - In many composite flowers, there are two types of flowers in each head. The ones in the center are called the disk flowers. The ones arranged around the disk flowers are the showy ray flowers. Mint Family - When you hear the word mint, you probably think of the pleasant flavor of peppermint. This flavor is produced by the oils of the peppermint plant, an important member of the mint family. - Other important members in the mint family include: - oregano, basil, sage, lavender, marjoram, balm, rosemary, and thyme, which are all used in cooking - salvia and coleus, which are used for decoration - Mint plants have a square stem and a strong smell Parsley Family - Most parsley plants’ flowers are extremely complex in design. - Many members of the parsley family are used as foods or seasonings. - Ex. carrot, celery, parsley, and dill - Several poisonous plants belong to the parsley family as well - Ex. poison hemlock and water hemlock Rose Family - Includes the plants with showy flowers and thorny stems known as garden roses. - Also included wild roses, with their open, five petal design. - Other members of the rose family include blackberries, raspberries, and strawberries. - A number of fruit trees are members of the rose family, such as the apple, apricot, cherry, nectarine, peach, pear, plum, and almond. Pea Family - One of the largest families of flowering plants - Members are called legumes - Several members of the pea family provide us food, such as English peas, beans, peanuts and lentils - Other members, such as alfalfa, clover, and vetch, prevent soil erosion and provide forage for farm animals. - Some members are used to decorate, such as wisteria vine, redbud, locust, laburnum, and mimosa trees. - A type of pea that you do not want growing in your yard is kudzu. Mustard Family - Many of our vegetables come from the leaves, stems, or roots of plants in the mustard family. - We eat leaves and stems of cabbage, collards, kale, & turnips. - The turnip, radish, and rutabaga supply us with edible roots. - We eat the flower buds of broccoli plants and the actual flowers of cauliflowers. Lily Family - Diverse plant with some surprising members. - Daylilies bloom in the summer, while most members of the lily family bloom in early spring, such as tulip, trillium, and hyacinth. - Despite its cactus like appearance, aloe vera is a member of the lilies along with the yuccas, Joshua tree, and Spanish bayonet. Cashew Family - Most familiar member of the cashew family is the cashew tree. - However, cashew family is also known for the group to which three main poisonous plants belong: poison sumac, poison ivy, and poison oak. - Their leaves contain urushiol, an oily substance that can produce a severe rash. Nightshade Family - Many important food plants are in the nightshade family, such as potatoes, peppers, tomatoes, and eggplants. - The nightshade family also has many poisonous plants, such as the deadly nightshade, the woody nightshade, and tobacco. Grass Family - Among the most important groups of flowering seed plants, yet most people have never stopped to realize that grass has flowers. - The grasses may be considered the most important group of plants on Earth. - Many land animals depend on grass for food whether it be indirectly or directly. - Man has taken the grasses and developed from them high-yielding cereal crops, including wheat, barley, rye, oats, rice, and corn. - We also benefit indirectly from grass when we eat meat because livestock are raised on grains and forage grasses. - Turf grasses are used as lawn coverings, athletic fields, golf courses, and playgrounds. - Common turf grasses are Kentucky blue grass, bent grass, Bermuda, ryegrass, and Bahia grass. Things to Notice about a Grass Plant - Grass plant has a stolon, which is a creeping stem that grows above ground. The stem is round and mostly hollow except at the node where the leaf attaches. - The leaves of grass have a sheath that seems to wrap partially around the stem at the base of the leaf. The plant grows from the base of the sheath, so when the plant gets mowed, it will keep growing. - The flower cluster is small and inconspicuous. From the flower the fruits, or grains, grow. - Humans cannot digest the leaves and stems of grasses, but animals can. Annuls, Biennials, and Perennials - Plants are commonly classified according to their growth cycles. - An annual is a plant that develops from a seed and produces new seeds in a single growing season. These short-lived plants are among the most useful to mankind (peas, beans, grains, and many others.) - A biennial is a plant that lives through two growing seasons to complete their life cycles. Plants like beets, cabbage, turnips, carrots, and many others. - During the first year, they do not grow large but devote their resources to storing food in its taproot. - During the second year, the plant uses it reserves of food to produce flowers and seeds. - Most of the time these plants are harvest after the first year to obtain its food and we never see their flowers. - A perennial lives from year to year and bloom each season. They may be herbs or woody. Legumes, Bacteria & Nitrogen Cycle - Members of the pea family are commonly referred to as legumes. - The identifying feature of this family is its fruit, which takes the form of a pod called a legume. - Clovers, vetches, peas, alfalfa, beans, and other legumes are important crop plants because they enrich the soil as they grow. - The element nitrogen is an essential part of proteins, but plants cannot directly use nitrogen out of the air to make protein. They can only use nitrogen that has been combined into special compounds of nitrogen and oxygen called nitrates. - Nitrogen-fixing bacteria growing on the roots of legumes convert nitrogen from air into ammonia and nitrates, which the plant absorbs through its roots to convert to proteins. When the plants die, their nitrogen-containing compounds are incorporate into the soil, making it more fertile for other plants. - Nitrifying bacteria provide nitrates to the soil from decomposing plants and animals, and lightening produces small amounts of nitrate in the soil from nitrogen in the air. The main source of nitrates comes from synthetic fertilizers. Legumes, Bacteria & Nitrogen Cycle - The movement of nitrogen from air, into the soil, and back into air is called the Nitrogen Cycle. - The Nitrogen Cycle is essential to life on earth because plants, animals, and humans all require nitrogen to live. - Denitrifying bacteria in the soil convert unused nitrates back into atmospheric nitrogen to complete the cycle. • https://www.youtube.com/watch?v=K5EOZenSSB8 Monocots & Dicots - The seed of an angiosperm plant contains special structures called cotyledons, which are used to store food until the seed begins to grow. - All the families of angiosperms can be placed into two categories, monocots or dicots, based on the number of cotyledons per seed. Monocots have one, where dicots have two. Most families are dicots. - Monocots and dicots are distinguished by other characteristics like monocots have parallel veins, petals in multiples of 3, and a fibrous root system. Dicots have broad, flat leaves with branching veins, petals in multiples of 4 or 5, and a taproot system. Broadleaf Trees - Trees, the largest of all plants, may live for hundreds or even thousands of years and continue to grow throughout their life. - When you observe trees, the first thing you notice is the leaves. Whether they are broad, flat leaves, long, narrow leave, or needlelike leaves. - Broadleaf trees are flowering seed plants with broad flat leaves that are dicots. - Most broadleaf trees (beeches, maples, oaks, and others) have dense, hard wood, termed hardwoods. However, a few such as basswoods and cottonwoods actually have soft, lightweight wood. - In addition to having broad, flat leave and hard wood, most in temperate regions are deciduous, meaning they lose their leaves each fall and are bare all winter. - Evergreen trees in contrast retain their leaves throughout the winter. Broadleaf Trees - The trunk does not reach the top of the tree but divided into spreading branches, giving the crown a rounded shape. - Most do not have pretty, showy flowers, however, but tiny, drab flowers. They appear as long, tassel-like clusters of tiny grayish or yellowish-green flowers. These flowers, called catkins, can be seen early spring on oaks, willows, cottonwoods, poplars, and birches. catkins cottonwood oak Maples - Their fruits have tiny wings to catch the breeze so that the seeds will scatter. This form of a fruit is called a samara. Magnolias - Symbol of the South. Magnolias range from the biggest bloom (up to 10 inches) to the smallest of blooms. Birches - Known for their thin, smooth bark that peels in layers. - Indians used this for canoes, and pioneers used it for roofing material and writing paper. Beech - Most important are the American beech, American chestnut and Oak. Elm - Among 15 different elms, the American elm is the most familiar because of its shade and street border. - Many elms have lived as long as 200 years. Walnut - All members have compound leaves that are very similar in shape. - Walnuts, pecans, and hickories. Oaks - One of the most familiar and useful group of trees, known for their wood and acorns. Dogwoods - Bracts are beautiful, creamy white structure that surround the flowers like petals but are actually modified leaves. Ashes - 16 varieties grow in the US. - White ash and red ash are the most common. - Recognized by their compound leaves.
