| amoeba |
a tiny living thing made of only one cell. Amoebas move by changing their shape. They eat by wrapping their bodies around their food. Amoebas live in fresh and salt water, soil, and in animals. Most kinds of amoebas can only be seen through a microscope. |
| bacteria |
microscopic organisms that often play a role in the decay of living things, the process of fermentation, and sometimes in causing disease. Bacteria are each made up of only one cell, but different kinds of bacteria can take different shapes. These organisms live in all parts of the earth including oceans, deserts, glaciers, hot springs, and in the bodies of most living things. While some kinds of bacteria are dangerous, most kinds are useful because they help in the digestion of food, in the making of soil, in the creation of medicines, and in many other natural processes. |
| bacterium |
singular form of "bacteria." Bacteria are tiny living things made up of one cell each. Bacteria live in most living things and in all parts of the earth. Most bacteria are useful to people, but some are harmful because they can cause disease. |
| cell phone |
a telephone that operates using radio signals and therefore requires no wires. A cell phone can be taken with one anywhere but may not function if it is too far away from a radio transmitter to receive signals. |
| cellular phone |
a telephone that can be taken anywhere and does not use wires. A cellular phone uses radio signals that are sent out from many different points called "cells." A cellular phone gets its signals from whatever cell is closest to it at the moment. A cellular phone is often called a "cell phone." |
| corpuscle |
a cell that moves freely in the blood. Red and white blood cells are corpuscles. |
| cytoplasm |
the thick liquid substance that holds all the parts that are inside a cell. |
| dry cell |
an electric battery cell in which the chemicals are stored as a paste that will not spill. |
| egg1 |
a cell in a female animal or in some kinds of plants that can develop into a new individual after it is fertilized. [1/2 definitions] |
| honeycomb |
a group of many small cells made of wax in which bees store their honey. Each cell has thin walls and six sides. [1/3 definitions] |
| message |
to send a message to (someone), especially using a cell phone or computer. [1/4 definitions] |
| mobile |
a telephone that operates using radio signals and therefore requires no wires. A mobile can be taken with one anywhere but may not function if it is too far away from a radio transmitter to receive signals. "Mobile" has the same meaning as "cell phone." [1/3 definitions] |
| nervous system |
the system of nerves and nerve centers in most animals with more than one cell. |
| nuclear |
of, or having to do with, or being the nucleus of an atom or a cell. [1/3 definitions] |
| nucleus |
the part of a cell that contains chromosomes, which control growth and reproduction in most living things. [1/3 definitions] |
| paramecium |
a living thing made of one cell that lives in fresh water. Paramecia can only be seen through a microscope. Paramecia are protozoans, tiny organisms that are similar to animals. |
| protozoan |
a tiny living thing that is similar to an animal but has only one cell or lives as a colony of single cells. Protozoans include amoebas and paramecia. |
| red blood cell |
a cell in the blood that carries oxygen to the body's tissues. |
| sperm1 |
a cell made by male animals. These cells fertilize the eggs made by a female, so that the animal can reproduce. |
| T cell |
a type of white blood cell that defends the body against certain diseases. |
| text |
a written message sent by a cell phone; text message. [3/5 definitions] |