Science Lecture Review: Astronomy, Ecology, Electricity, and Chemistry

Practice flashcards covering introductory concepts in Astronomy, Ecology, Electricity, and Chemistry based on lecture.

Astronomical Unit (A.U.)

The distance from the Sun to the Earth, approximately $150\,million\,km$, used to measure distances within our solar system.

Light Year (L.Y.)

The distance it takes light to travel in one year, equivalent to $9.46\,trillion\,km$.

Parsec (pc)

A unit of distance beyond the solar system equal to $3.26\,LY$ or $31\,trillion\,km$.

Astronomy

The scientific study of the objects of the universe beyond the Earth’s atmosphere.

Cosmology

The study of the origins of the universe.

Laika

The first animal (a dog) in space, launched in $1957$.

Yuri Gagarin

The first human in space, representing the Soviet Union in $1961$.

Neil Armstrong

The first human on the moon in $1969$, representing the USA.

NASA

National Aeronautics and Space Administration; the American government agency responsible for the civilian space program.

International Space Station (ISS)

A habitable satellite launched in $1998$ that serves as a laboratory for microgravity in low orbit around the Earth.

International Astronomical Union (IAU)

A group of professional astronomers with the authority to classify celestial objects; they reclassified Pluto as a dwarf planet in $2006$.

Gravity

The force causing two objects with mass to attract each other, affected by size (mass) and distance.

Orbit

A path that a less massive object takes around a more massive object due to gravity.

Orbital period

The amount of time a less massive object takes to complete one full orbit, which is $365.26\,days$ for Earth.

Ecliptic

The shared common plane of all orbits in our solar system.

Inner Planets

Mercury, Venus, Earth, and Mars; characterized as small, rocky planets that can be walked on.

Outer Planets

Jupiter, Saturn, Uranus, and Neptune; characterized as ringed gas giants.

Asteroid Belt

A region of millions of irregularly shaped rocky objects in orbit between Mars and Jupiter.

Kuiper Belt

A donut-shaped region $30\text{-}50\,AU$ from the Sun containing icy bodies and Pluto.

Comet

A 'dirty snowball' with a nucleus of rocks, ice, and frozen gases that forms a head and tails when heating up near the sun.

Meteor

A meteoroid that has entered Earth’s atmosphere and is burning up due to friction, often called a 'shooting star'.

Revolution

The movement of one object around another object.

Rotation

The movement of Earth around its axis, which causes the day and night cycle.

Winter Solstice

Occurring on December $22$, it is the longest night and shortest day of the year.

Summer Solstice

Occurring on June $22$, it is the longest day and shortest night of the year.

Nuclear Fusion

The process in a star's core where $Hydrogen+Hydrogen \rightarrow Helium + energy$, acting as an outward force against gravity.

Nebula

A giant collection of dust and gas where new stars are born.

James Webb telescope

Launched in $2021$ and located at Lagrange point, it uses infrared sensors to gather info from deep space.

Ecosystem

A group of biotic and abiotic components that work together to sustain life.

Biodiversity

The number of different types of organisms in an ecosystem.

Ecological Niche

The role an organism plays in an ecosystem, including its response to and effect on other components.

Autotrophs

Organisms, also known as producers, that can make their own food using chemical reactions like photosynthesis.

Photosynthesis

The process where producers use sun energy to turn carbon dioxide and water into glucose and oxygen ($6CO_2 + 6H_2O \rightarrow C_6H_{12}O_6 + 6O_2$).

Cellular Respiration

The chemical reaction that releases stored energy from glucose ($C_6H_{12}O_6 + 6O_2 \rightarrow 6CO_2 + 6H_2O$).

Trophic level

The position an organism occupies in a food chain.

Apex predator

A top carnivore that is not hunted by any other organism in its ecosystem.

Carrying capacity (K)

The maximum population an ecosystem can support indefinitely.

Optimal range

The upper and lower ends of a limiting factor that provide the best conditions for a population to survive.

Mutualism

A symbiotic relationship where both organisms benefit ($+/+$).

Commensalism

A symbiotic relationship where one organism benefits and the other is not affected ($+/0$).

Troposphere

The layer of the atmosphere where life exists and weather occurs.

Eutrophication

A process where enriched waters lead to algal blooms, which die and deplete water oxygen when decomposed by aerobic bacteria.

Biomagnification

The increase in concentration of toxins as they move up the food chain or trophic levels.

Transpiration

The release of water vapor from plants as part of the water cycle.

Endangered

A wildlife species facing imminent extinction or extirpation.

Invasive species

A type of introduced species that is harmful to its new environment because it overpopulates and out-competes native species.

Law of Conservation of Charge

A law stating that in a closed system, charges can never be created or destroyed.

Insulators

Materials, such as plastic or wool, that resist the flow of electrons.

Conductors

Materials, such as copper or gold, that allow the flow of electrons.

Induced charge separation

The separation of charges in a neutral object caused by the proximity of a charged object without direct contact.

Grounding

The act of connecting an object to the earth to prevent the build-up of charges.

Voltage

Also known as potential difference, it is the amount of energy supplied by a source to push electrons through a circuit, measured in volts.

Current

The rate of flow of electrons, measured in amperes ($amps$).

Resistance

The amount of opposition to the flow of electrons, measured in ohms.

Kirchoff's Law of Voltage

States that the voltage supplied by the source must equal the sum of the voltage drops used by all the loads ($V_{T} = V_1 + V_2 + V_3 + \dots$).

Ohm’s Law

States that voltage is directly proportional to current, expressed by the formula $V = IR$.

HHPS

Hazardous Household Product Symbols; safety symbols designed for products used in the home.

Matter

Anything that has mass and volume.

Lustre

A physical property of a substance describing how shiny or lustrous it is.

Viscosity

A physical property describing how easily a liquid can pour or how thick it is.

Malleability

A solid substance's ability to be bent or hammered into a thin sheet without breaking.

Combustibility

A chemical property describing whether a substance will catch fire in the presence of oxygen and heat.

Proton

A subatomic particle in the nucleus with a positive charge and a mass of $1\,amu$; its number determines the element's identity.

Neutron

A neutral subatomic particle in the nucleus with a mass of $1\,amu$ that stabilizes the nucleus.

Electron

A negative subatomic particle found in orbitals with a negligible mass of $0.00055\,amu$, involved in chemical bonding.

Cation

A positively charged ion.

Anion

A negatively charged ion.

Dmitri Mendeleev

The Russian chemist who developed the periodic table in $1869$.

Alkali Metals

Soft, silvery, and highly reactive metals in Group 1 that are stored under mineral oil.

Noble Gases

Group 18 elements that are colorless, odorless, and inert because they have full valence orbitals.

Molecular Compound

A substance formed from the chemical bonding of two or more nonmetals.