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Ck 12: Life Science: Chromosomal Disorders
[Free Registration/Login may be required to access all resource tools.] Some children are born with genetic defects that are not carried by a single gene. Instead, an error in a larger part of the chromosome or even in an entire...
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Ck 12: Life Science: Types of Mollusks
[Free Registration/Login may be required to access all resource tools.] There are approximately 160,000 living species and probably 70,000 extinct species of mollusks. They are typically divided into ten classes, of which two are...
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Ck 12: Life Science: Vision Correction
[Free Registration/Login may be required to access all resource tools.] You probably know people who need eyeglasses or contact lenses to see clearly. Maybe you need them yourself. Lenses are used to correct vision problems. Two of the...
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Ck 12: Life Science: Bacteria Nutrition
[Free Registration/Login may be required to access all resource tools.] Like all organisms, bacteria need energy, and they can acquire this energy through a number of different ways. Learn more about bacteria nutrition in this learning...
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Ck 12: Life Science: Food and Nutrients
[Free Registration/Login may be required to access all resource tools.] Refusing one meal won't stunt your growth. But lack of proper food over a period of time can lead to malnutrition. That means the body is not getting enough...
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Ck 12: Life Science: Fungi Reproduction
[Free Registration/Login may be required to access all resource tools.] Different fungi reproduce in different ways. Many fungi reproduce both sexually and asexually. However, some reproduce only sexually and some only asexually. Asexual...
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Ck 12: Life Science: Importance of Reptiles
[Free Registration/Login may be required to access all resource tools.] Reptiles play an important role in the life of humans. In addition to playing an important role in many food chains, which keep the populations of small animals...
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Ck 12: Life Science: Lizards and Snakes
[Free Registration/Login may be required to access all resource tools.] Lizards and snakes belong to the largest order of reptiles, Squamata. Lizards are a large group of reptiles, with nearly 5,000 species, living on every continent...
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Ck 12: Life Science: Molecular Evidence for Evolution
[Free Registration/Login may be required to access all resource tools.] Chimpanzees and humans turn out to be very similar - if you look at their DNA. When scientists determined the entire genetic code of both humans and chimpanzees,...
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Ck 12: Life Science: Respiration
[Free Registration/Login may be required to access all resource tools.] We breathe because we need oxygen. Breathing also releases carbon dioxide from our bodies into the air. The respiratory system is the body system that brings air...
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Ck 12: Life Science: Harmful Bacteria
[Free Registration/Login may be required to access all resource tools.] With so many species of bacteria, some are bound to be harmful. Harmful bacteria can make you sick. They can also ruin food and be used to hurt people. Learn more...
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Ck 12: Life Science: Hearing and Balance
[Free Registration/Login may be required to access all resource tools.] What do listening to music and riding a bike have in common? It might surprise you to learn that both activities depend on your ears. The ears do more than just...
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Ck 12: Life Science: Helpful Bacteria
[Free Registration/Login may be required to access all resource tools.] Can we survive without bacteria? Could bacteria survive without us? Learn more about helpful bacteria in this learning module produced by CK-12.
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Ck 12: Life Science: Humans and Primates
[Free Registration/Login may be required to access all resource tools.] The great apes are the members of the biological family Hominidae, which includes four living genera: chimpanzees, gorillas, humans, and orangutans. Learn more about...
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Ck 12: Life Science: Insect Reproduction and Life Cycle
[Free Registration/Login may be required to access all resource tools.] Most insects can reproduce quickly within a short period of time, which means they evolve faster and can adjust to environmental changes. Most reproduce by sexual...
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Ck 12: Life Science: Mammal Reproduction
[Free Registration/Login may be required to access all resource tools.] Mammals don't typically lay eggs, but monotremes are the exception. All other mammals give birth to live young and belong to one of two categories, the marsupials...
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Ck 12: Life Science: Scientific Theories
[Free Registration/Login may be required to access all resource tools.] Today most people realize that microorganisms, such as bacteria or viruses, are the cause of disease. This concept is known as the germ theory of disease, one of the...
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Ck 12: Life Science: Control of Insects
[Free Registration/Login may be required to access all resource tools.] Ladybugs won't hurt you. But they are dangerous to some other insects! Ladybugs eat plant-harming bugs known as aphids. Since they have an appetite for aphids,...
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Ck 12: Life Science: Importance of Echinoderms
[Free Registration/Login may be required to access all resource tools.] Echinoderms are important for the ecosystem. They are also a source of food and medicine for humans. Learn more about the importance of echinoderms in this learning...
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Ck 12: Life Science: Cell Biology
[Free Registration/Login may be required to access all resource tools.] A cell is the smallest structural and functional unit of an organism. Learn more about cell biology in this learning module produced by CK-12.
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Ck 12: Life Science: Predation
[Free Registration/Login may be required to access all resource tools.] Predation is another mechanism in which species interact with each other. Predation is when a predator organism feeds on another living organism or organisms, known...
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Ck 12: Life Science: Symbiosis
[Free Registration/Login may be required to access all resource tools.] Symbiosis describes a close and long-term relationship between different species. At least one species will benefit in a symbiotic relationship. There are three...
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Ck 12: Life Science: Respiratory System Organs
[Free Registration/Login may be required to access all resource tools.] When you think of the processes of breathing, the lungs probably come to mind. The lungs are the main organ of the respiratory system. However, many other organs are...
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Ck 12: Life Science: Reproduction in Seedless Plants
[Free Registration/Login may be required to access all resource tools.] Seedless plants can reproduce asexually or sexually. Some seedless plants, like hornworts and liverworts, can reproduce asexually through fragmentation. When a small...