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7TH Grade Science [Science 7]

    |--Modern Classification System
    |--The Five Kingdoms
    |--The Human Body
    |--Reproduction and Development
    |--Human Health
    |--Composition of the Earth
    |--Structure of the Earth
    |--Atoms and Molecules
    |--Elements and Compounds
    |--Mixtures and Solutions
    |--Newton's Laws
    |--Work, Energy and Power
    |--Gravity and Motion

    Required Textbook: A Beka, Order and Reality, Work-Text, Pensacola, Florida, current edition.

    [a] Focus on the Life Sciences.
    [i] All living organisms are composed of cells, from just one to many trillions, whose details usually are visible only through a microscope.
    [ii] Learn how cells function similarly in all living organisms.
    [iii] Distinguish plant cells from animal cells, including chloroplasts and cell walls.
    [iv] Learn the function of different parts of the cell. The nucleus is the repository for genetic information, mitochondria liberate energy for the work that cells do and that chloroplasts capture sunlight energy for photosynthesis.
    [v] Cells divide to increase their numbers through a process of mitosis, which results in two daughter cells with identical sets of chromosomes. In multicellular organisms the component cells differentiate as the organism develops.
    [vi] A typical cell of any organism contains genetic instructions that specify its traits. Those traits may be modified by environmental influences.
    [vii] Learn the differences between the life cycles and reproduction methods of sexual and asexual organisms.
    [viii] Sexual reproduction produces offspring that inherit half their genes from each parent. An inherited trait can be determined by one or more genes. Plant and animal cells contain many thousands of different genes and typically have two copies of every gene.
    [ix] DNA (deoxyribonucleic acid) is the genetic material of living organisms and is located in the chromosomes of each cell.

    [b] In Earth and Life History, evidence from rocks allows us to understand the evolution of life on Earth.
    [i] Earth processes today are similar to those that occurred in the past and slow geologic processes have large cumulative effects over long periods of time.
    [ii] The history of life on Earth has been disrupted by major catastrophic events, such as major volcanic eruptions or the impacts of asteroids.
    [iii] The rock cycle includes the formation of new sediment and rocks and that rocks are often found in layers, with the oldest generally on the bottom.
    [iv] Evidence from geologic layers and radioactive dating indicates that the Earth is approximately 4.6 billion years old and that life on this planet has existed for more than 3 billion years.
    [v] Movements of Earth's continental and oceanic plates through time, with associated changes in climate and geographic connections, have affected the past and present distribution of organisms.
    [vi] Most events mentioned in this subject occur in the geologic time scale.

    [c] The anatomy and physiology of plants and animals illustrate the complementary nature of structure and function.
    [i] Plants and animals have levels of organization for structure and function, including cells, tissues, organs, organ systems, and the whole organism.
    [ii] Organ systems function because of the contributions of individual organs, tissues, and cells. The failure of any part can affect the entire system.
    [iii] Bones and muscles work together to provide a structural framework for movement.

    [d] Physical Principles in Living Systems underlie biological structures and functions.
    [i] Visible light is a small band within a very broad electromagnetic spectrum, for an object to be seen, light emitted by or scattered from it must be detected by the eye.
    [ii] Light travels in straight lines if the medium it travels through does not change.
    [iii] Simple lenses are used in a magnifying glass, the eye, a camera, a telescope, and a microscope.
    [iv] White light is a mixture of many wavelengths (colors) and that retinal cells react differently to different wavelengths.
    [v] Light can be reflected, refracted, transmitted, and absorbed by matter. The angle of reflection of a light beam is equal to the angle of incidence.
    [vi] Compare joints in the body (wrist, shoulder, thigh) with structures used in machines and simple devices (hinge, ball-and-socket, and sliding joints).
    [vii] Levers confer mechanical advantage, the application of this principle applies to the musculoskeletal system.
    [viii] Contractions of the heart generate blood pressure and that heart valves prevent backflow of blood in the circulatory system.

    [e] Scientific progress is made by asking meaningful questions and conducting careful investigations.
    [i] Develop your own questions and perform investigations.
    [ii] Select and use appropriate tools and technology (including calculators, computers, balances, spring scales, microscopes, and binoculars) to perform tests, collect data, and display data.
    [iii] Use a variety of print and electronic resources (including the World Wide Web) to collect information and evidence as part of a research project.
    [iv] Communicate the logical connection among hypotheses, science concepts, tests conducted, data collected, and conclusions drawn from the scientific evidence.
    [v] Construct scale models, maps, and appropriately labeled diagrams to communicate scientific knowledge (e.g., motion of Earth's plates and cell structure).
    [vi] Communicate the steps and results from an investigation in written reports and oral presentations.


    1.1 - Modern Classification System

    1.1 - The Five Kingdoms

    The animal kingdom is at once the Kingdom most and least familiar to us. Almost all of the animals we commonly think of: mammals, fish, and birds; belong to a single subgroup within one of the 33 Phyla comprising the Animal Kingdom.
    When you think of an animal, you usually think of something like a cat, a dog, a mouse, or a tiger. All told, around 800,000 species have been identified in the animal kingdom; most of them in the Arthropod phylum. In fact, some scientists believe that if we were to identify all species in the tropical rain forests the ranks of Arthropoda would swell to over 10 million species! Most people do not normally think of a clam, a jellyfish, or an earthworm as an animal. Yet all of them belong to the kingdom of animals. The science of classifying organisms is called taxonomy.
    Here are highlights of the larger members of the animal kingdom:
    Spinal Cords (Chordata): All animals having a spine, including fish, mammals, birds, reptiles, amphibians, sharks, and eels are grouped into Chordata. Because these animals are so familiar to us, biologists have come up with elaborate classification schemes including subphyla, superclasses, infraorders, and the like. The vast majority (including all the Classes listed above) fit into the subphylum Vertebrata; those having a backbone. Subphyla Agnatha, jawless fish, includes certain eels such as the Lamprey. Cephalochordata and Tunicata round out the list of subphyla with fairly obscure creatures called Lancelets and Tunicates, respectively.
    Joint-Legs (Arthropoda): Animal that have jointed legs and no spine, belong in the Arthropoda phylum. This includes most, if not all, of the animals we commonly call "bugs" as well as the crustaceans. Scientists have described 500,000 species of arthropods and believe that up to 10,000,000 species are alive today. ... In order to study living things, scientists classify each organism according to its: Kingdom Phylum Class Order Family Genus Species Usually, a species is called by its genus name (capitalized) followed by its species name (lower case), so a human being is called Homo sapiens. In Latin that means "wise man." To date there are five kingdoms: Animalia, which is made up of animals; Plantae, which is made up of plants; Protista, which is made up of protists (single-celled creatures invisible to the human eye); Fungi, which is made up of mushrooms, mold, yeast, lichen, etc; and Monera, which is made up of the three types of bacteria. The next category is the Phylum. There are several phyla within each kingdom. The phyla start to break the animals (or plants, fungi, etc) into smaller and more recognizable groups. The best known phylum is Chordata, which contains all animals with backbones (fish, birds, mammals, reptiles, amphibians). There is also Arthropoda (insects, spiders, crustaceans); Mollusca (snails, squid, clam); Annelida (segmented worms); Echinodermata (starfish, sea urchins) and many, many more. The next category that makes up the phyla is the Class. The class breaks up animals into even more familiar groups. For example, the phylum Chordata is broken down into several classes, including Aves (birds), Reptilia (reptiles), Amphibia (amphibians), Mammalia (mammals) and several others. The next category is the Order. Each class is made up of one or more orders. Mammalia can be broken down into Rodentia (mice, rats), Primates (Old- and New-World monkeys), Chiroptera (bats), Insectivora (shrews, moles), Carnivora (dogs, cats, weasels), Perissodactyla (horses, zebras), Artiodactyla (cows), Proboscidea (elephants) and many more. Orders can then be broken down into Families. The order Carnivora can be broken down into Canidae (dogs), Felidae (cats), Ursidae (bears), Hyaenidae (hyaenas, aardwolves), Mustelidae (weasels, wolverines), and many more. The next category is the Genus. The family Felidae, for example, can be broken down into Acinonyx (cheetah), Panthera (lion, tiger), Neofelis (clouded leopard) and Felis (domestic cats). Finally, the genus is broken down into the Species. The genus Panthera can be broken down to include Panthera leo (lion) and Panthera tigris (tiger). Note that the genus is placed in front of the species. Main group of Invertebrates are : The largest and most commonly studied phyla of animals are: 1. Porifera (sponges) 2. Cnidaria (jellyfish, hydras, sea anemones, Portuguese man-of-wars, and corals) 3. Platyhelminthes (flatworms, including planaria, flukes, and tapeworms) 4. Nematoda (roundworms, including rotifers and nematodes) 5. Mollusca (mollusks, including bivalves, snails and slugs, and octopuses and squids) 6. Annelida (segmented worms, including earthworms, leeches, and marine worms) 7. Echinodermata (including sea stars, sea cucumbers, sand dollars, and sea urchins) 8. Arthropods (including arachnids, crustaceans, millipedes, centipedes, and insects) 9. Chordata (animals with nerve chords - this group includes the vertebrates)

    3.1 - The Human Body

    4.1 - Composition of the Earth

    5.1 - Atoms and Molecules

    6.1 - Newton's Laws

    [1] A Beka, Order and Reality, Work-Text, Pensacola, Florida.
    [2] Milani, Jean P., et. al. Biological Science: An Ecological Approach (6th edition), Kendall/Hunt Publishing Company, Iowa, 1987
    [3] Margulis, Lynn, Diversity of Life: The Five Kingdoms, Enslow Publishers, Inc., New Jersey, 1992