| A | B |
|---|
| cytoskeleton | the cytoplasmic network of protein filaments and tubes that plays an essential role in cell movement, shape and division |
| microtubule | one of the small tubular fibers composed of the protein tubulin that are found in the cytoplasm of eukaryotic cells, that compose the cytoskeleton, and that play a role in cell structure and movement |
| microfilament | a fiber found inside eukaryotic cells that is composed mainly of the protein actin and that has a role in cell structure and movement |
| cilium | a hairlike structure arranged in tightly packed rows that projects from the surface of some cells, plural is cilia |
| flagellum | a few, long hair like structures made of microtubules used for movement |
| centriole | an organelle that is composed of two short microtubules that has an active role in mitosis |
| cell wall | a rigid structure that surrounds the cell membrane and provides support to the cell |
| central vacuole | in some protists and in most plant cells, a large, fluid-filled organelle that stores water, metabolic wastes and other materials |
| plastid | an organelle of plant cells that contains specific substances and performs specific functions for the cell; examples include chloroplasts and chromoplasts |
| chloroplast | an organelle found in plant cells and the cells of other eukaryotic organisms where photosynthesis occurs |
| thylakoid | a membrane system found within chloroplasts that contains the components for photosynthesis |
| chlorophyll | a green pigment that is present in most plant cells, that gives plants their characteristic green color and that reacts with sunlight, water and carbon dioxide to form carbohydrates |
| plasma membrane | a thin, phospholipid and protein molecule bilayer that encapsulates a cell and controls the movement of materials in and out of the cell through active or passive transport |
| intermediate filament | part of the cytoskeleton, rods that anchor the nucleus and other organelles into place in the cell |
| autophagy | the process where lysosomes digest worn out organelles |
| vesicle | small, spherically shaped sacs that are surrounded by single membrane and that are classified by their contents |
| cristae | folds of the inner mitochondrial membrane where cell respiration occurs |
| endosymbiosis | a theorized process in which early eukaryotic cells were formed from simpler prokaryotes |
| nuclear pores | small holes in the nuclear envelope, that allow RNA and other molecules to enter and exit the nucleus |
| fluid mosaic model | states that the phospholipid bilayer behaves like a fluid more than it behaves like a solid |
| integral proteins | proteins embedded within the lipid bilayer of the plasma membrane and function as cell surface markers, receptor and transport proteins |
| peripheral proteins | proteins on the surface of the plasma membrane, not embedded in it and function as labels or enzymes |
| nucleoplasm | similar to the cell's cytoplasm, the jellylike liquid which holds the contents of the nucleus |
| chromatin | the threadlike, loose form of DNA when a cell is not dividing |
| cisternae | the membranous tubes and sacs of the endoplasmic reticulum |
