| A | B |
|---|
| Cell Wall | made of cellulose; allows water, oxygen, carbon dioxide and specific dissolved materials to pass through; only found in plant cells. |
| Protoplasm | All the living materials in a cell. |
| Cell Membrane | thin, felxible envelope that surrounds the cell;helps control movement of materials into and out of the cell. |
| Nucleus | The control center of the cell; controls all activities of the cell. |
| Nucleic acids | Large complex molecules found in the nucleus - called nucleic acids. |
| DNA | one type of nucleic acid; deoxyribonucleic acid; stores the information needed to build proteins. |
| RNA | A type of nucleic acid; ribonucleic acid - reads the DNA messages and guides the protein-making process, can leave the nucleus through a nuclear pore. |
| Nuclear Membrane | Thin membrane that separates the nucleus from the rest of the cell; allows materials to pass into and out of the nucleus. |
| Chromosomes | Made of DNA, direct the activities of the cell and pass on the traits of the cell to new cells. |
| Nucleolus | "little nucleus"; made of RNA and protein; important in makeing some of the cell's RNA. |
| Endoplasmic reticulum | Maze of tubular passageways leading out from the nuclear membrane; involved in the transport of proteins; other materials can be transported to the outside of the cell through this system. |
| Ribosomes | Grainlike bodies, made up mainly of the nucleic acid RNA; the protein making sites of the cell, often attached to the endoplasmic reticulum or floating freely in the cytoplasm. |
| Mitochondria | Supply most of the energy for the cell, rod-shaped structures referred to as "powerhouses" of the cell. |
| Vacuoles | large, round, water-filled sac floating in the cytoplasm; act as storage tanks; can store waste products or food and other materials needed by the cell. |
| Lysosomes | Common in animal cells; rarely seen in plant cells; small, round structures involved with the digestive activities of the cell; contain enzymes that break down large food molecules. |
| Chloroplasts | irregularyly shaped green structures found in the cytoplasm; contain a green pigment called chlorophyll; found only in plant cells. |
