Figure A shows the speeds of some of the fastest cells known and how they move. Figure B shows different cells’ size (x-axis) and maximum speed (y-axis).

Ciliates move using hairlike structures called cilia. Flagellates move using whiplike structures called flagella. They make many of the same types of moves, including swimming, walking, elastic jumping (movements by contracting cilia or flagella) or hydrodynamic jumping (using cilia or flagella to leap forward).

Prokaryotes include bacteria and archaea. Surface-based motility means that a cell moves along a surface. Cell protrusion or extrusome is when something pops out of a cell. And contraction without translocation means that the size of the cell changes but the whole cell’s position doesn’t.

Cells above the dashed line in Figure B move more than 10 body lengths per second. Cells above the solid line move faster than 100 body lengths per second.

algae: A group of single-celled and multicellular organisms, once considered plants (they aren’t). As aquatic organisms, they grow in water. Like green plants, they depend on sunlight to make their food.

annual: Adjective for something that happens every year.

bioengineer: Someone who applies engineering to solve problems in biology or in systems that will use living organisms.

cell: (in biology) The smallest structural and functional unit of an organism. Typically too small to see with the unaided eye, it consists of a watery fluid surrounded by a membrane or wall. Depending on their size, animals are made of anywhere from thousands to trillions of cells. Most organisms, such as yeasts, molds, bacteria and some algae, are composed of only one cell.

cilia: (singular cilium) Small hairlike features that occur on the surface of some cells and larger tissue structures. They can move and their wavelike motion can propel liquids to move in a particular direction. Cilia play an important role in many biological functions throughout the body.

data: Facts and/or statistics collected together for analysis but not necessarily organized in a way that gives them meaning. For digital information (the type stored by computers), those data typically are numbers stored in a binary code, portrayed as strings of zeros and ones.

DNA: (short for deoxyribonucleic acid) A long, double-stranded and spiral-shaped molecule inside most living cells that carries genetic instructions. It is built on a backbone of phosphorus, oxygen, and carbon atoms. In all living things, from plants and animals to microbes, these instructions tell cells which molecules to make.

eukaryote: Any organism whose cells have a nucleus. Eukaryotes include all multicellular creatures (such as plants, animals and fungi) as well as certain types of single-celled microorganisms.

flagella: (sing. flagellum)   A thread-like structure that comes out of certain types of cells. The term derives from the Latin word for whip. And that's because the structures serve like oars to help these cells travel. 

freshwater: A noun or adjective that describes bodies of water with very low concentrations of salt. It’s the type of water used for drinking and making up most inland lakes, ponds, rivers and streams, as well as groundwater.

microbiology: The study of microorganisms, principally bacteria, fungi and viruses. Scientists who study microbes and the infections they can cause or ways that they can interact with their environment are known as microbiologists.

migration: (v. migrate) Movement from one region or habitat to another, especially regularly (and according to the seasons) or to cope with some driving force (such as climate or war). An individual that makes this move is known as a migrant.

nucleus: Plural is nuclei. (in biology) A dense structure present in many cells. Typically a single rounded structure encased within a membrane, the nucleus contains the genetic information.

oceanographer: Someone who works in the branch of science that deals with the physical and biological properties and phenomena of the oceans.

organism: Any living thing, from elephants and plants to bacteria and other types of single-celled life.

outlier: (in statistics) An observation that lies outside the range of the rest of the data.

photosynthesis: (verb: photosynthesize) The process by which green plants and some other organisms use sunlight to produce foods from carbon dioxide and water.

planet: A large celestial object that orbits a star but unlike a star does not generate any visible light.

prokaryote: Any single-celled organism that does not have a nucleus or membrane-bound organelles.

solid: Firm and stable in shape; not liquid or gaseous.

toxin: A poison produced by living organisms, such as bacteria, algae and certain plants (such as poison ivy). Bees, spiders, snakes and other animals also produce toxins. These are referred to as venoms.