Matter, Chemistry, Space, Biology, and Environmental Science

Matter & Chemistry

  • Element

    • A pure substance composed of only one type of atom.

  • Compound

    • A substance formed from two or more different elements that are chemically combined.

  • Atom

    • The smallest particle of an element that retains its chemical properties.

Changes of State

  • Melting

    • The process of a solid transforming into a liquid. This occurs when particles gain energy.

  • Freezing

    • The process of a liquid transforming into a solid. This occurs when particles lose energy.

  • Boiling

    • The process of a liquid changing to gas, where particles move very quickly.

  • Changes of State

    • Defined as physical changes initiated by adding or removing energy.

Particle Theory of Matter

  1. All matter consists of particles.

  2. Particle motion is always in motion.

  3. Increased energy results in faster particle movement.

  4. Particles exert attractive forces on each other.

Groups of the Periodic Table

  • Groups

    • Vertical columns in the periodic table; elements within the same group exhibit similar properties and have the same number of valence electrons.

Ion Charge

  • The ion charge is the electrical charge an atom attains after gaining or losing electrons.

Suspension

  • A suspension is a mixture in which particles settle out over time due to gravity.

Electricity & Forces

  • How Lightning Works

    • Charge accumulation occurs in clouds; electrons migrate to the ground resulting in a significant electrical discharge (lightning).

  • Conductors

    • Materials that facilitate the flow of electricity, such as metals and water.

  • Insulators

    • Materials that impede the flow of electricity, including rubber and plastic.

  • Gravitational Force

    • A natural force that draws objects toward one another, influencing their motion and interactions.

Space & Astronomy

  • Solar Eclipse

    • An event when the Moon obstructs the Sun from view from Earth.

  • Lunar Eclipse

    • An event when the Earth obstructs sunlight from reaching the Moon.

  • Tides on Earth

    • Primarily caused by the gravitational pull exerted by the Moon on Earth's water.

Life Cycle of Stars

  • Medium Mass Star

    • Evolves into a red giant, transforms into a planetary nebula, and ultimately becomes a white dwarf.

  • Low Mass Star

    • Burns at a slow rate and has a prolonged lifespan.

  • High Mass Star Life Cycle

    • Goes from a nebula to a massive star, then undergoes a supernova explosion, ultimately becoming a neutron star or a black hole.

Planetary Characteristics

  • Why Mercury Has No Weather

    • Absence of an atmosphere prevents heat retention and air movement.

  • Earth’s Address

    • Earth is located within the Solar System, which is a part of the Milky Way Galaxy, within the Universe.

  • Tropic

    • Imaginary lines, such as the Tropics of Cancer and Capricorn, where the Sun can be observed directly overhead at noon.

  • Planet Order

    • The planets in our solar system, in order from the Sun, are: Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, and Neptune.

  • Nebula

    • A massive cloud of gas and dust where stellar formation occurs.

  • Geocentric Model

    • An outdated astronomical model positioning Earth at the universe's center.

  • The Sun

    • A star primarily composed of hydrogen and helium gases.

  • Mercury

    • The planet closest to the Sun.

  • Venus

    • The hottest planet in the solar system due to its thick atmosphere.

  • Jupiter

    • The largest planet in our solar system.

  • Uranus

    • Notable for its unique rotational axis that lies on its side.

  • The Core of Earth

    • The highly dense and hot center of Earth, mainly comprised of iron and nickel.

  • Milky Way

    • The galaxy that contains our solar system.

Biology & Ecology

  • Ecosystem

    • A dynamic interaction between living (biotic) and non-living (abiotic) components.

  • Symbiosis

    • A close interaction between two different species sharing a habitat.

Types of Symbiosis

  • Mutualism

    • A relationship in which both organisms benefit from each other.

  • Commensalism

    • A relationship where one organism benefits, while the other remains unaffected.

  • Parasitism

    • A relationship where one organism benefits at the expense of another organism being harmed.

  • Example of Parasitism

    • A tick feeding on a mammal, where the tick derives nourishment while harming the mammal.

Population & Community

  • Population

    • A group consisting of individuals of a single species inhabiting a specific area.

  • Community

    • The sum of all populations residing in a particular area.

Biosphere

  • Biosphere

    • The global sum of all living organisms on Earth.

  • Predator

    • An organism that actively hunts other animals for food.

  • Prey

    • An animal that is hunted and consumed by predators.

  • Herbivore

    • An organism that primarily consumes plant material.

  • Carnivore

    • An organism that primarily consumes other animals.

  • Omnivore

    • An organism that consumes both plant and animal matter.

  • Decomposer

    • Organisms, such as fungi and bacteria, that break down dead organic material.

  • Scavenger

    • An organism that feeds on dead animals, such as vultures.

Role of Decomposers

  • Decomposers are vital as they recycle nutrients back into the soil, contributing to ecosystem health.

  • Nutrients

    • Essential substances that organisms require for growth and survival.

Food Chain and Pyramid

  • Food Chain

    • A visual representation of the energy transfer from one organism to another in an ecosystem.

  • Producer

    • An organism that creates its own food, primarily plants through photosynthesis.

  • Consumer

    • Organisms that feed on other organisms for energy.

  • Food Pyramid

    • A model illustrating how energy decreases at each successive level of the food chain.

Biomes & Environment

  • Tundra

    • Characterized by cold temperatures, minimal vegetation, and permafrost soil conditions.

  • Deciduous Forest

    • Forests where trees lose their leaves in autumn, experiencing four distinct seasons.

  • Biomes

    • Large ecological regions with similar climates and organisms.

  • Abiotic Factors

    • Non-living components of an ecosystem, including sunlight, water, soil, and temperature.

  • Biotic Factors

    • Living components of an ecosystem, including all flora and fauna.

  • Types of Soil

    • Sand: Drains water quickly.

    • Clay: Holds water effectively.

    • Loam: Optimal soil for supporting plant growth due to its balance of properties.

Cycles & Processes

  • Photosynthesis

    • The process by which plants utilize sunlight to synthesize glucose (food) and produce oxygen as a byproduct.

  • Primary Purpose of Photosynthesis

    • To create food in the form of glucose for the plant.

  • Cellular Respiration

    • The process by which cells convert glucose and oxygen into energy, releasing carbon dioxide and water.

  • Carbon Cycle

    • The continuous movement of carbon through both living (biotic) and non-living (abiotic) components of the environment.

  • Deforestation & the Carbon Cycle

    • The removal of trees leads to increased levels of carbon dioxide (CO₂) in the atmosphere due to fewer plants available to absorb it.

  • Transpiration

    • The release of water vapor from the leaves of plants into the atmosphere.

Nitrogen Cycle

  • Nitrogen Fixation

    • The process by which bacteria convert atmospheric nitrogen gas (N₂) into forms usable by living organisms.

  • Nitrification

    • The conversion of ammonia (NH₃) into nitrates (NO₃⁻) by bacteria to make nitrogen available for plant uptake.

  • Denitrification

    • The biological conversion of nitrates back into nitrogen gas, returning it to the atmosphere.

Environmental Issues

  • Biomagnification

    • The process where toxins become more concentrated in organisms as they move up the food chain.

  • Bioaccumulation

    • The gradual accumulation of toxic substances, such as pesticides, in individual organisms over time.

  • Importance of Biodiversity

    • Biodiversity enhances the stability and resilience of ecosystems.

  • Three Types of Biodiversity

    • Genetic Biodiversity: Varieties of genetic information within species.

    • Species Biodiversity: The variety of species within a habitat or ecosystem.

    • Ecosystem Biodiversity: The diversity of ecosystems within a particular area.

  • Impact of Fewer Grasshoppers

    • Reduced grasshopper populations can lead to insufficient food sources for predators, disrupting ecosystem balance.

  • Competition

    • The struggle between organisms for limited resources, such as food, water, and shelter.

  • Human Activities & Air Pollution

    • Caused by actions such as burning fossil fuels, industrial output, and vehicle emissions.

  • Human Activities to Promote Conservation

    • Strategies include reducing waste, recycling materials, and protecting natural habitats.

  • Waste & Conservation

    • Minimizing waste is crucial for protecting ecosystems and conserving essential resources.