| A | B |
|---|
| chromatin | the granular material visible within the nucleus |
| chromosome | distinct threadlike structures containing the genetic information that is passed from one generation of cells to the next |
| nucleolus | a small dense region contained in most nuclei. This is where the assembly of ribosomes begins. |
| nuclear envelope | a double membrane layer that surrounds the nucleus |
| cytoskelton | a network of protein filaments that helps the cell to maintain its shape. It is also involved in many forms of cell movement. |
| microtubule | hollow tubes of proten about 25 nanometers in diameter. They maintain cell shape and can also serve as tracks along which organelles move. |
| microfilament | long, thin fibers that function in the movement and support of the cell. |
| ribosome | small particles of RNA and protein. Proteins are asssembled here. |
| endoplasmic reticulum | the organelle in which components of the cell membrane are assembled and some proteins are modified. |
| golgi apparatus | the stack of membranes from which proteins produced by the rough endoplasmic reticulum are moved |
| lysosome | are small organelles filled with enzymes. One function is to break down lipids, carbohydrates and proteins from food into particles that can be used by the rest of the cell. |
| vacuole | these are saclike structures that cells use to store materials such as water, salts, proteins, and carbohydrates. |
| chloroplast | use the energy from sunlight to make energy rich food molecules in a process known as photosynthesis |
| mitochondrian | are organelles that release energy from stored food molecules. They use energy from food to make high-energy compounds that the cell can use to power growth, development and movement. |
