Term | Definition |
Cell wall | outer layer of plant cells that supports and protects cell |
cell membrane | a phospholipid bilayer with embedded globular proteins that controls the flow of matter in and out of the cell |
chromatin (Chromosomes/DNA) | (chromatin when uncoiled): long strands of DNA found within the nucleus of a cell |
christae | short, fingerlike projections formed by folding of the inner membrane of the mitochondria |
cytoplasm | all the material (fluid) outside the nucleus, other than the organelles |
cytoskeleton | internal framework of the cell made of microtubules, actin filaments, and intermediate filaments |
gogli apparatus | structures made of groups of flattened sacs used to store, package, and export proteins and other materials produced in the cell |
lysosome | lysosomes are vesicles filled with hydrolytic enzymes that help to digest food or break down old structures for recycling or removal |
matrix | the inner fluid space in the mitochondria; contains DNA, ribosomes, and enzymes that break down carbohydrates to provide energy needed to produce ATP during cellular respiration |
nuclear envelope | contains nuclear pores; controls the movement of materials into and out of the nucleus |
nuclear pore | opening in the nuclear envelope that permits the passage of proteins into the nucleus and ribosomal subunits out of the nucleus |
nucleolus | the dark, spherical area of the nucleus; aids in the production of rRNA (ribosomal RNA), a structural component of ribosomes |
organelles | subcellular structures surrounded by membranes |
polysomes | string of ribosomes simultaneously translating regions of the same mRNA strand during protein synthesis; also called polyribosome |
ribosomes | structures found on rough ER (some are free floating) that assemble proteins |
rough endoplasmic reticulum | rough ER is characterized by large numbers of ribosomes on its surface; it produces proteins that secreted by the cell |
smooth endoplasmic reticulum | smooth ER lacks ribosomes and is responsible for the production of lipids, such as steroid hormones |
vacuoles | a membrane-enclosed storage structure that is usually filled with water and chemicals |
vesicle | vesicles are small vacuoles used to transport materials |
plasma membrane | a microscopic membrane of lipids and proteins that forms the external boundary of the cytoplasm of a cell or encloses a vacuole, and that regulates the passage of molecules in and out of the cytoplasm. |