Life Science MCAS Review: Cells, Systems, Reproduction, Evolution

1. Mrs. McCarthy’s MCAS Review Life Science

2. Life Science 6th Grade Curriculum • Classification of Organisms • Structure and Function of Cells • Systems in Living Things • Reproduction & Heredity • Evolution & Biodiversity • Living Things & Their Environment • Energy & Living Things • Changes in Ecosystems Over Time

3. Structure and Function of Cells Cells are the basic units of life. All living things are made of cells. Cells are very small and can only be seen with a microscope.

4. Cells • There are different types of cells: • Animal Cells • Plant Cells • Some living things are multi-cellular • Example: plant, animal • Some living things are unicellular • Example: bacteria, yeast

5. Parts of the Cell Cell Wall-the outside of the cell that strengthens the cell membrane Cell Membrane- keeps cytoplasm in; allows nutrients in & waste out Chloroplasts-hold green chlorophyll for photosynthesis Vacuoles- store water & fluid Nucleus- holds cell’s DNA Cytoplasm-fluid in cell Mitochondria- breakdown food in the cell

6. Plant Cell Plant Cells are found in plants. Unlike Animal Cells, Plants Cells contain: Cell Wall & Chloroplasts so that they can make food using photosynthesis.

7. Animal Cell Animal Cells are found in animals. Unlike Plants Cells, Animal Cells do not contain: Cell Wall & Chloroplasts.

8. Cellular Functions • Cells function similar to living organisms: • Extracting Energy from Food • Disposing of Waste • Reproduction (Mitosis)

9. Heredity • All living things have traits. • Traits are stored in chromosomes. • These are passed on from one generation to the next in genes. • Human cells contain about 30,000 different genes on 23 different chromosomes. • Punnett Squares show possible inheritance.

10. Reproduction There are 2 types of reproduction: • Sexual: 2 Parent Cells Join Together to Form a New Individual; Offspring Inherit Half of Their Genes from each Parent • Example: Plants & Animals • Asexual: only 1 Parent Cell is Needed; Parent Cell is Copied; Mitosis Occurs • Example: Single-celled Organisms

11. Genes of DNA Cells & Body Tissues Organs Systems

12. Systems in Living Things • The Human Body’s Major Systems: • Digestion: Food Energy • Respiration: Breathing • Reproduction: Population • Circulation: Blood Flow • Excretion: Waste • Immune: Protection from Disease • Movement, Control, Coordination: Moving, Thinking, Planning, Processing

13. Classification of Organisms Classification is the arrangement of organisms into orderly groups based on their similarities. Levels: Kingdom- large general group Phylum- Classes- Orders- Families- Genus- Species- one kind Hint: King----Kingdom Philip---Phylum Came--Classes Over----Orders For------Families Grape--Genus Soda---Species Kingdom’s are continuously broken down into classified groups until species

15. Kingdoms Plantae Protista • All living organisms belong to one of the kingdoms • There are five Kingdoms: • Bacteria- E. coli, • Protista- single-celled organisms • Plantae- plants, flowers & trees • Fungi- fungus, mold & mushrooms • Animalia- animals, people, pets, bugs Animalia Fungi Bacteria

16. Evolution & Biodiversity • Evolution: organisms adapt and change over time • Evidence: geology, fossils, comparative anatomy • Extinctions: many species have not been able to adapt to habitat changes over time Survival of the fittest

17. Living Things & Their Environment • Organisms interact with one another and have different functions within an ecosystem that enable the ecosystem to survive. • Circle of Life

18. Food Web • Food Web- Energy from food flows from one organism to another • Parts of the Food Web: • Producers- use sunlight to make food • Example: Plants • Consumers-eat producers & organisms • Example: animals • Decomposers-break down remains of dead organisms • Example: bacteria & fungi

20. Decomposers & Nitrogen Cycle • Decomposers- Living organisms break down dead plants & animals (bacteria, fungus) • Nitrogen is produced in this cycle. • Broken down material is used for compost and has nutrients in it that contribute to the system.

22. Photosynthesis • Plants use energy from sunlight to make sugars from carbon dioxide and water through photosynthesis. • This food can be used immediately, stored for later use, or used by other organisms.

23. Photosynthesis • The process where plants capture light energy from the sun and change it into food.

24. Water Cycle

25. Ecosystems • Ecosystem- the habitat of living organisms • Land: Forests, Grasslands, Deserts, Tundra • Marine: Beaches, Seafloor, Reefs • Freshwater: Moving Water, Still Water, Wetlands

26. Earth's Ecosystems

27. Changes in EcosystemsOver Time • Changes in the ecosystem can cause extinction, habitat damage, & global warming. • Ecosystems are effected by: • Pollution • Resource Depletion • Alien Species • Human Population Growth • Habitat Destruction

28. Energy Resources Energy Resources: Natural, Fossil Fuels, & Alternatives Natural Resources include wood, gasoline, wind Fossil Fuels: nonrenewable energy resource - Made over millions of years from buried organisms - Create environmental pollution problems - Examples: coal, natural gas, petroleum Alternatives: renewable & easy to replace resources - Most are cleaner & safer. - Examples: Solar, Wind, Hydroelectric, Biomass, Nuclear (Dangerous)