Science Vocabulary for 7th Grade
62 terms
JamWise Education Team·Updated March 2026
In 7th grade, students in the middle school (6-8) band encounter 62 essential science vocabulary terms. These words form the foundation for classroom discussions, reading comprehension, written assignments, and standardized assessments. Mastering this vocabulary gives students the language they need to express their understanding with clarity and confidence.
Below you will find every science term for 7th grade, organized by topic where applicable. Each term links to a detailed definition page with grade-level explanations, related vocabulary, and connections to JamWise learning resources.
earth-science
View topic hubAbsolute age
Absolute age is the actual age of a rock or fossil in years, determined through radioactive dating methods.
Chemical weathering
Chemical weathering is the breakdown of rock through chemical reactions that change the minerals in the rock.
Continental drift
Continental drift is the theory that continents have slowly moved over Earth's surface throughout geologic history.
Convection current
A convection current is a circular flow of material caused by heating — hot material rises and cool material sinks.
Earthquake
An earthquake is a sudden release of energy in Earth's crust caused by the movement of tectonic plates along faults.
Erosion
Erosion is the process by which weathered rock and soil are transported from one location to another by water, wind, ice, or gravity.
Fault
A fault is a crack in Earth's crust where blocks of rock have moved past each other.
Mechanical weathering
Mechanical weathering is the physical breakdown of rock into smaller pieces without changing its chemical composition.
Mineral
A mineral is a naturally occurring, inorganic solid with a definite chemical composition and crystal structure.
Relative age
Relative age tells whether a rock layer or fossil is older or younger than another, without giving an exact number of years.
Rock cycle
The rock cycle is the continuous process by which rocks transform between igneous, sedimentary, and metamorphic types through melting, weathering, heat, and pressure.
Seismic wave
A seismic wave is a wave of energy that travels through Earth, usually caused by an earthquake.
Tectonic plate
A tectonic plate is a massive slab of Earth's lithosphere that moves slowly over the asthenosphere.
Topography
Topography is the shape and features of Earth's surface, including mountains, valleys, plains, and rivers.
Volcano
A volcano is an opening in Earth's crust where magma, ash, and gases escape from deep inside the planet.
life-science
View topic hubActive transport
Active transport is the movement of molecules across a cell membrane using energy, from low concentration to high concentration.
Allele
An allele is one of the different forms of a gene. For example, a gene for flower color may have a purple allele and a white allele.
Asexual reproduction
Asexual reproduction involves only one parent and produces offspring that are genetically identical to the parent.
Biome
A biome is a large region of Earth characterized by its climate, plants, and animals.
Cell membrane
The cell membrane is a thin, flexible barrier that surrounds a cell and controls what enters and leaves.
Cell wall
The cell wall is a rigid outer layer found in plant cells that provides structure and support.
Cellular respiration
Cellular respiration is the process by which cells break down glucose using oxygen to release energy (ATP), carbon dioxide, and water.
Chloroplast
A chloroplast is an organelle found in plant cells that captures sunlight energy and uses it to make food through photosynthesis.
Chromosome
A chromosome is a tightly coiled structure of DNA that contains genes. Human cells have 46 chromosomes.
Cytoplasm
Cytoplasm is the gel-like fluid inside a cell that holds the organelles in place.
Diffusion
Diffusion is the movement of molecules from an area of high concentration to an area of low concentration.
DNA
DNA (deoxyribonucleic acid) is the molecule inside cells that carries the genetic instructions for building and running an organism.
Dominant trait
A dominant trait is a trait that appears in the offspring when at least one dominant allele is present.
Ecology
Ecology is the study of how living organisms interact with each other and their environment.
Food web
A food web is a diagram showing the complex network of overlapping food chains in an ecosystem.
Gene
A gene is a segment of DNA that carries the instructions for making a specific protein or trait.
Heredity
Heredity is the passing of traits from parents to offspring through genes.
Homeostasis
Homeostasis is the ability of an organism to maintain stable internal conditions even when the external environment changes.
Mitochondria
Mitochondria are organelles that break down food molecules to release energy for the cell. They are called the powerhouses of the cell.
Mitosis
Mitosis is the process by which a cell divides its nucleus to produce two identical daughter cells.
Niche
A niche is the specific role an organism plays in its ecosystem, including what it eats, where it lives, and how it interacts with other species.
Organ
An organ is a structure made of different tissues working together to perform a specific job in the body.
Organ system
An organ system is a group of organs that work together to perform a major body function.
Osmosis
Osmosis is the diffusion of water through a semipermeable membrane from an area with more water to an area with less water.
Photosynthesis
Photosynthesis is the process by which plants and some bacteria use sunlight energy to convert carbon dioxide and water into glucose and oxygen.
Recessive trait
A recessive trait only appears when an organism has two copies of the recessive allele.
Ribosome
A ribosome is a tiny organelle that reads genetic instructions and builds proteins for the cell.
Sexual reproduction
Sexual reproduction involves two parents combining genetic material to produce offspring with a unique mix of traits.
Succession
Succession is the gradual process by which ecosystems change and develop over time after a disturbance.
Symbiosis
Symbiosis is a close, long-term relationship between two different species living together.
Tissue
A tissue is a group of similar cells working together to perform a specific function.
Vacuole
A vacuole is a large sac inside a cell that stores water, food, and waste materials.
physical-science
View topic hubAtom
An atom is the smallest unit of an element that still has all the properties of that element.
Chemical reaction
A chemical reaction occurs when substances interact to form new substances with different properties.
Compound
A compound is a substance made of two or more elements chemically bonded in a fixed ratio, with properties different from its elements.
Conservation of mass
The law of conservation of mass states that matter cannot be created or destroyed in a chemical reaction — the total mass stays the same.
Electromagnetic spectrum
The electromagnetic spectrum is the full range of electromagnetic radiation, from radio waves to gamma rays, with visible light in the middle.
Element
An element is a pure substance made of only one type of atom that cannot be broken down by chemical means.
Endothermic reaction
An endothermic reaction is a chemical reaction that absorbs heat energy from the surroundings.
Exothermic reaction
An exothermic reaction is a chemical reaction that releases heat energy into the surroundings.
Mixture
A mixture is a combination of two or more substances that are not chemically bonded and can be separated by physical means.
Molecule
A molecule is two or more atoms bonded together. A water molecule is made of two hydrogen atoms and one oxygen atom.
PH scale
The pH scale measures how acidic or basic a substance is, from 0 (very acidic) to 14 (very basic), with 7 being neutral.
Product
A product is a new substance formed as a result of a chemical reaction.
Reactant
A reactant is a substance that enters into a chemical reaction and is changed.
Solubility
Solubility is the maximum amount of a substance that can dissolve in a given amount of solvent at a specific temperature.
Wave
A wave is a disturbance that transfers energy from one place to another without transferring matter.