| A | B |
|---|
| organism | a living thing |
| cell | the basic unit of structure and function of living things |
| unicellular | a type of organism that is made up of a single cell |
| multicellular | a type of organism that is made up of many cells |
| development | the process of change that occurs duirng an organism's life to produce a more complex organism |
| stimulus | a change in an organism's surroundings that causes the organism to react |
| response | an action or change in behavior that occurs as a result of a stimulus |
| reproduce | the production of offspring that are similar to the parents |
| spontaneous generation | the mistaken idea that living things arise form nonliving sources |
| controlled experiment | an experiment in which all of the variables except for on remain the same |
| manipulated variable | the one factor that a scientist changes to test a hypothesis during an experiment |
| autotroph | an organism tha makes its own food |
| heterotroph | an organism that cannot make its own food |
| homeostasis | the process by which an organism's internal environment is kept stable in spite of changes in the external environment |
| microscope | an instrument that makes small objects look larger |
| compound microscope | a light microscope tha thas more than one lens |
| cell theory | a widely accepted explanation of the relationship between cells and living things |
| magnification | the ability to make things look larger than they are |
| covex lens | a curved lens in which the center is thicker than the edges |
| resolution | the ability to clearly distinguish the individual parts of an object |
| organelle | a tiny cell structure that carries out a specific function within the cell |
| cell wall | a rigid layer of nonliving material that surrounds the cells of plants an some other orgnisms |
| cell membrane | the outside boundary of a cell; controls which substances can enter or leave the cell |
| nucleus | the control center of the cell that directs the cell's activities; contains the chemical instructions that direct all the cell's activities and determine the cell's charateristics |
| chromatin | material in cells that contain DNA and carries genetic information |
| cytoplasm | the region of the cell located inside the cell membrane (in prokaryotes) or between the cell membrane and nucleus (in eukaryotes); contains gel-like material and cell organelles |
| mitochondria | rod-shaped cell structures that produce most of the energy needed to carry out the cell's functions |
| endoplasmic reticulum | a cell structure that forms a maze of passageways in which proteins and other materials are carried from on part of the cell to another. |
| ribosome | a tiny structure in the cytoplasm of a cell where proteins are made |
| golgi body | a structure in a cell that receives proteins and other newly formed materials from the endoplasmic reticulum, packages them, and distributes them to other parts of the cell. |
| chloroplast | a structure in the cells of plants and some other organisms that captures energy from sunlight and uses it to produce food |
| vacuole | a water-filled sac inside a cell that acts as a storage area |
| lysosome | a small round cell structure that contains chemicals that break down large food particles into smaller ones |
| prokaryote | an organism whose cells lack a nucleus and some other cell structures |
| eukaryote | an organism with cells that contain nuclei and other cell structures |
| fossil | the preserved remains or traces of an organism that lived in the past |
