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Ck 12: Life Science: Plant Reproduction and Life Cycle
[Free Registration/Login may be required to access all resource tools.] The life cycle of a plant is very different from the life cycle of an animal. Humans are made entirely of diploid cells (cells with two sets of chromosomes). Our...
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Ck 12: Life Science: 2.1 Elements and Compounds
Learn how basic elements form molecules to support life.
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Ck 12: Life Science: Importance of Biodiversity
[Free Registration/Login may be required to access all resource tools.] Biodiversity is a measurement of the amount of variation of the species in a given area. More specifically, biodiversity can be defined as the variety of life and...
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Ck 12: Life Science: Theory of Evolution by Natural Selection
[Free Registration/Login may be required to access all resource tools.] Do you ever wonder why some birds are big like ostriches and some birds are small like robins? Or why a lion has a mane while a leopard has spots? In the 19th...
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Ck 12: Life Science: Fossils
[Free Registration/Login may be required to access all resource tools.] Fossils are the preserved remains of animals, plants, and other organisms from the distant past. By studying fossils, evidence for evolution is revealed....
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Ck 12: Life Science: 1.7 Safety in the Life Sciences
Review the safety precautions while performing scientific investigations.
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Ck 12: Life Science: Photosynthesis
[Free Registration/Login may be required to access all resource tools.] Plants are producers, which means they are able to make their own food, as well as "food" for other organisms. Plants are also autotrophs - they collect energy from...
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Ck 12: Life Science: 12.22 Carbon Cycle
Understand the role that the carbon cycle plays in the ecosystem.
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Ck 12: Life Science: 12.26 Health Hazards of Air Pollution
See how air pollution affects human health.
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Ck 12: Life Science: 11.62 Humoral Response
Learn about the human body's immune response to pathogens.
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Ck 12: Life Science: 12.6 Human Population
Understand stages of human population growth.
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Ck 12: Life Science: 12.5 Population Growth Limits
Discover how ecosystems respond to population growth limits.
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Ck 12: Life Science: 11.21 Cardiovascular System
Understand the structure and function human cardiovascular system.
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Ck 12: Life Science: 11.28 Blood Diseases
Understand how blood illnesses affect human health.
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Ck 12: Life Science: 11.1 Human Body
Explore the levels of organization in the human body.
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Ck 12: Life Science: 10.12 Lizards and Snakes
Explore the characteristics and behaviors of lizards and snakes.
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Ck 12: Life Science: 10.5 Cartilaginous Fish
Understand the behaviors and characteristics of cartilaginous fish.
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Ck 12: Life Science: 7.12 Plant Hormones
Understand how plant hormones allow plants to live in their environment.
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Ck 12: Life Science: 5.7 Types of Archaea
Explore the diversity of the domain Archaea.
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Ck 12: Life Science: 5.1 Viruses
Understand the genetics and characteristics of viruses.
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Ck 12: Life Science: 4.6 Molecular Evidence
Explore the molecular evidence for evolution.