7th Grade Curriculum Life Science 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

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

Classification Levels

Kingdoms All living organisms belong to one of the 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

Fundamental Characteristics Cell Type Eukaryote Prokaryote Ability to get food Autotroph (producer) Heterotroph (consumer) # of cells in body Unicellular (single) Multicellular (many)

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.

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

Plant Cell Plant Cells are found in plants. Unlike Animal Cells, Plants Cells contain: Cell Wall & Chloroplasts

Animal Cell Animal Cells are found in animals Unlike Plants Cells, Animal Cells contain: Centrioles

Parts of the Eukaryote Cell Cell Membrane- keeps cytoplasm in; allows nutrients in & waste out Nucleus- holds cell’s DNA Nucleolus – makes ribosomes Cytoplasm-fluid in cell Endoplasmic reticulum – Ribosomes – make protein Golgi apparatus – Vesicle – transports proteins Mitochondria – breakdown food in the cell Centriole – used during mitosis

Additional Parts of a Plant Cell Cell Wall-the outside of the cell that strengthens the cell membrane Chloroplasts-hold green chlorophyll for photosynthesis Vacuoles- store water & fluid AND… NO CENTRIOLES NO LYSOSOMES

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

Molecules (DNA, protein) Cells & Body Tissues Organs Systems

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

So Many Systems… Body Systems Rap (with handout)

Human Body Systems

Heredity All living things have traits. Trait information (gene) is stored in chromosomes. These are passed on from one generation to the next in genes. Human cells contain ~30,000 different genes on 23 different chromosomes. Punnett Squares show possible inheritance.

Monohybrid Crosses

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

What does this show?

What does this show?

Dividing Body Cells (Growth and Repair)

Making Gametes (Sex Cells)

Parent Daughter cells

Evolution & Biodiversity Evolution: populations adapt and change over time through natural selection (ORGANISMS DO NOT EVOLVE) Evidence: geology, fossils, comparative anatomy Extinctions: many species have not been able to adapt to habitat changes over time Survival of the (fittest) best suited to the environment

Evolution Evolution: populations adapt and change over time through natural selection (ORGANISMS DO NOT ADAPT) Natural Selection – change in phenotypes over many generations Predict what will happen to the fur coat color of these mice after many generations. VIDEO

Evidence Geology

Evidence Fossils

Evidence Comparative anatomy

Extinction Extinctions: many species have not been able to adapt to habitat changes over time

Biodiversity Anole 3 min video Increased variation in population can allow for new species to develop Forming new species increases biodiversity VIDEO

Living Things & Their Environment Organisms interact with one another and have different functions within an ecosystem that enable the ecosystem to survive. Symbiotic Relationships Parasitism Commensalism Mutualism Predator / Prey relationship

Predator / Prey relationship

Symbiotic relationships Living in close contact with another species. Parasitism Commensalism Mutualism

Roles in an Ecosystem Producers- use sunlight to make food Example: Plants Consumers-eat producers & organisms Example: animals Decomposers-break down remains of dead organisms • Example: bacteria & fungi

Energy in an Ecosystem Food Web- Energy from food flows from one organism to another Can you find the producers? Can you find the consumers? Name a… primary consumer secondary consumer tertiary consumer

Food Chain

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.

Water Cycle

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.

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

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

Earth's Ecosystems

Changes in Ecosystems Over 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

Gradual Change in Ecosystem

How many factors of ecosystem change can you find?