Comprehensive Study Guide: Earth Science, Energy, and Cell Biology
The Solar System and Earth's Origins
The Sun's Mass: The sun makes up of the solar system's total mass.
Star Composition: Stars are composed of hot hydrogen gas.
Earth's Age and Lifespan:
Earth is approximately years old.
The projected life span of Earth is years.
The Big Bang Theory:
The universe started approximately years ago.
It began at a single point and has kept expanding ever since.
Geography and Timezones:
Prime Meridian: The starting point for longitude ().
Latitude: Coordinates measuring .
Timezones: There are exactly global timezones.
Earth's Atmosphere and Water Resources
Atmospheric Composition:
Nitrogen:
Oxygen:
Other Gases:
Atmospheric Layers (from highest to lowest altitude):
Exosphere
Thermosphere
Mesosphere
Stratosphere
Troposphere
Freshwater Distribution:
Ice, lakes, and rivers hold of all freshwater on Earth.
The majority of this freshwater is frozen.
The Water Cycle Components:
Evaporation: Liquid water turning into vapor.
Condensation: Water vapor turning into clouds.
Precipitation: Rain, snow, or sleet falling to Earth.
Runoff: Water flowing across the surface into bodies of water.
Geology: Rock Types and Earth's Structure
Three Types of Rocks:
Igneous: Forms specifically when lava cools down.
Sedimentary: Forms when forces break down a rock into fragments and it gets compressed over time.
Metamorphic: Forms when extreme temperatures inside the Earth change existing rocks into new varieties.
Layers of the Earth:
Crust: The outer "shell." It consists of continental and oceanic crust and contains all three rock types.
Mantle: The middle layer and the largest by volume.
Core: A dense ball of solid iron. It is extremely hot. The Outer Core is liquid.
Nonrenewable Energy Resources
Current Usage: Fossil fuels and nuclear energy provide of energy in the U.S.
Fossil Fuels:
Advantages: Fossil fuels store chemical energy. When burned, they transform this energy into electrical energy. They are relatively inexpensive and easy to transport.
Disadvantages: They are nonrenewable (oil estimated to run out in less than years). Obtaining them is harmful to the environment. They contribute heavily to pollution by releasing chemicals into the atmosphere.
Nuclear Energy:
Energy is released from atomic reactions via Nuclear Fission (splitting atoms).
The Process of Nuclear Energy Generation:
Uranium atoms are split, releasing thermal energy.
Thermal energy heats water, producing steam.
Steam turns a turbine connected to a generator.
The generator spins and produces electricity.
Management Solutions:
Reclamation/Reclaim: A process where mined land must be recovered with soil and replanted with vegetation.
Legislation: Laws like the Clean Air Act ensure mining and drilling are environmentally safe. The U.S. Atomic Energy Act includes regulations to protect humans from nuclear emissions.
Renewable Energy Resources
Definition: Resources that come from natural processes occurring for billions of years.
Solar Energy: Energy from the sun.
Solar Cells: Capture light energy and transform it into electrical energy.
Active Solar: Solar panels gather and store solar energy to heat water and homes and generate electricity.
Passive Solar: Uses design elements to capture energy in sunlight directly.
Wind Energy: Used since ancient times for sailing.
Wind Turbines: Used to produce electricity.
Wind Farm: A collection of multiple wind turbines.
Anedote: If you drop papers on the ground and they go everywhere, you have experienced wind energy.
Water Energy:
Hydroelectric Power: Electricity produced by flowing water. Requires a dam across a powerful river.
Tidal Power: Utilizes coastal areas with large differences between high and low tides. Water flows across turbines during high tide and flows back out when the tide lowers.
Geothermal Energy: Thermal energy from Earth's hot core flowing outward.
People drill wells to reach hot rocks or magma.
This heats water to make steam, which turns turbines connected to generators.
Biomass Energy: Energy produced by burning organic matter (wood, food scraps, alcohol).
Ethanol: Made from sugars in plants. Often blended with gasoline to reduce oil use and carbon monoxide pollutants.
Biodiesel: Made from vegetable oils and fats. It is the fastest-growing renewable fuel in the U.S. and produces few pollutants.
Fundamentals of Cell Biology
General Characteristics:
All cells are alive.
Humans have about cells (100 trillion).
Most organisms only have one cell.
All living things are organized, grow/develop, adapt, reproduce, and use energy.
Macromolecules:
Nucleic Acids: Store genetic information (DNA/RNA).
Lipids: Provide structure to the cell membrane.
Proteins: Some act as enzymes; others provide structure. They help cells communicate.
Carbohydrates: Used for energy.
Cell Types:
Prokaryotic Cells: Have no nucleus or other membrane-bound organelles. Most are unicellular.
Eukaryotic Cells: Contain a nucleus and specialized membrane-bound organelles.
Organelles and Structure:
Cell Membrane: A protective layer made of lipids and proteins (acting like a "fence").
Cell Wall: A rigid and strong outside layer found in plants, fungi, and bacteria.
Cytoplasm: The liquid part of a cell inside the membrane where organelles are located.
Nucleus: The body of the cell; it stores DNA and genetic material.
Mitochondria: Organelles that break down food to release and process energy.
Chloroplasts: Capture light energy and convert it to chemical energy through photosynthesis.
Vesicles: Transport proteins around the cell.
Vacuoles: Store water and provide structural support.
Organelles: Similar to human cells (nucleus, mitochondria, ribosomes) but include chloroplasts, a cell wall, and a large central vacuole.
Transport Tissues: Roots, stems, and leaves.
Roots:
Functions: Anchor plant, absorb water and minerals from soil, and store food.
Types:
Taproot: One large main root with smaller roots branching off.
Prop Roots: Small roots above ground that support the plant.
Fibrous Roots: Systems consisting of many small branching roots.
Rhizoids: Root-like structures that anchor nonvascular plants without transport tissue.
Stems:
Functions: Support leaves/flowers, transport water/minerals to leaves, and transport sugar to roots.
Types: Woody (trees) and Herbaceous (flexible and green).
Plant Classification:
Nonvascular Plants: Lack specialized tissues for transporting water/minerals (e.g., mosses, liverworts, hornworts).
Vascular Seedless Plants: Have specialized tissue but produce spores instead of seeds (e.g., ferns, horsetails, club mosses).
Vascular Seed Plants: The most common type.
Gymnosperms: Non-flowering.
Angiosperms: Flowering.
Plant Reproduction and Genetics
Reproduction Types:
Asexual: Reproduction without seeds (e.g., growing from a leaf or stem).
Sexual: Involves male sex cells (sperm) and female sex cells (egg).
Life Cycle Stages: Gametophyte and Sporophyte.
Seed Development:
Pollination: Pollen lands on the female structure of a plant of the same species.
Fertilization: Triggered by pollination, leads to an embryo.
Dormancy: A period of no growth for the seed.
Germination: When the seed begins to grow.
Genetics and Adaptations:
Trait: A characteristic.
Phenotype: How a trait appears physically.
Genotype: The full set of genes.
Homeostasis: The ability to maintain internal conditions.
Meiosis: The process where a cell replicates and divides.
Mutations: Permanent changes in DNA. Can be random or caused by harsh chemicals/radiation.
Three Types of Adaptations:
Structural: A physical trait.
Behavioral: A specific action or behavior.
Functional: A biochemical change (e.g., hibernation).
Evolutionary Cycle: Mutation leads to variation, which leads to adaptation through natural selection.