7th Grade Science Vocabulary

Cell: The smallest unit of life that makes up living things. It is considered the fundamental structural, functional, and biological unit of all known organisms. All living things are composed of one or more cells, which handle the specialized tasks necessary for life.
Ecosystem: A community of living and nonliving things interacting. This biological system consists of all the organisms (the biotic component) in a given area, which interact with the physical environment (the abiotic component) including sunlight, soil, water, and air.
Photosynthesis: How plants use sunlight to make food. This complex biological process involves plants, algae, and certain bacteria converting light energy from the sun into chemical energy, typically producing oxygen as a byproduct while synthesizing glucose for food.

Atom: The tiny building block of all matter. Atoms are the smallest units of a chemical element that retain the characteristics of that element. They consist of a nucleus (containing protons and neutrons) surrounded by electrons.
Molecule: A group of atoms bonded together. A molecule is the smallest unit of a chemical compound that can take part in a chemical reaction, representing two or more atoms held together by chemical bonds.
Chemical Reaction: A process where substances change into new substances. This occurs when chemical bonds between atoms are formed or broken, resulting in a transformation of the molecular or ionic structure of the substances involved.
Density: How much mass is packed into a certain amount of space. It is a measurement of how tightly matter is compressed within a specific volume. The relationship is expressed by the mathematical formula: $ext{Density} = rac{ ext{Mass}}{ ext{Volume}}$

Force: A push or pull on an object. A force is an interaction that, when unopposed, will change the motion of an object. It can be caused by various factors, including gravity, magnetism, or physical contact.
Gravity: The force that pulls objects toward each other. This natural phenomenon is an attractive force exerted by all matter that has mass, and it is responsible for keeping planets in orbit and objects on the surface of the Earth.
Energy: The ability to do work or cause change. Energy exists in many forms, such as kinetic energy, potential energy, thermal energy, and electrical energy. It is essential for every physical and chemical change in the universe.