Terms : Hide Images
| 489386795 | eukaryotic cell | most of the DNA in this cell is in an organelle called the nucleus, which is bounded by a double membrane | |
| 489386796 | prokaryotic cell | DNA in this cell is concentrated in a region that is not membrane enclosed, called the nucleoid | |
| 489386797 | nucleoid | a dense region of DNA in a prokaryotic cell | |
| 489386798 | cytosol | the semi-fluid portion of the cytoplasm in which organelles and other components are found | |
| 489386799 | cytoplasm | the interior of a prokaryotic cell; the region between the nucleus and the plasma membrane of a eukaryotic cell | |
| 489386800 | plasma membrane | located at the boundary of every cell and functions as a selective barrier that allows sufficient passage of oxygen, nutrients, and wastes to service the cell | |
| 489386801 | nucleus | contains most of the genes in the eukaryotic cell (the ones that are not in the mitochindria or chloroplasts) | |
| 489386802 | nuclear envelope | the structure that encloses the nucleus, separating its contents from the cytoplasm; has a double membrane | |
| 489386803 | nuclear lamina | a netlike array of protein filaments that maintains the shape of the nucleus by mechanically supporting the nuclear envelope; line the nuclear side of the nuclear evelope | |
| 489386804 | chromosomes | structures that carry the genetic information; made up of material called chromatin | |
| 489386805 | chromatin | a comples of proteins and DNA that chromosomes are made of | |
| 489386806 | nucleolus | a prominent structure in the nucleus in which rRNA is synthesized from instructions in the DNA; proteins imported from the cytoplasm are assembled with rRNA into large and small ribosomal units; functions in regulation of some cellular processes such as cell division | |
| 489386807 | ribosomes | complexes made of ribosomal RNA and protein; the cellular components that carry out protein synthesis | |
| 489386808 | free vs. bound ribosomes | -free ribosomes are suspended in the cytosol -bound ribosomes are attached to the outside of the endoplasmic retticulum | |
| 489386809 | endomembrane system | includes the nuclear envelope, endoplasmic reticulum, Golgi apparatus, lysosomes, various kinds of vacuoles, and the plasma membrane; carries out various tasks in the cell including synthesis of proteins and their transport into the membranes and organelles or out of the cell, metabolism and movement of lipids, and detoxification of poisons | |
| 489386810 | vesicles | a sac made of membrane in the cytoplasm | |
| 489386811 | endoplasmic reticulum | an extensive membranous network of eukaryotic cells, continuous with the outer nuclear membrane and composed of ribosome-studded (rough) and ribosome free (smooth) regions | |
| 489386812 | rough ER | has ribosomes on the outer surface of the membrane; aids in synthesis of secretory and other proteins from bound ribosomes, adds carbohydrates to glycoproteins, produces new membrane | |
| 489386813 | smooth ER | lacks ribosomes; synthesis of lipids, metabolism of carbohydrates, calcium storage, detoxification of drugs and poisons | |
| 489386814 | transport vesicles | a tiny membrane sac in the cell's cytoplasm carrying molecules produced by the cell | |
| 489386815 | Golgi apparatus | stacks of flattened membranous sacs; has polarity; modification of proteins, carbohydrates, and phospholipids; synthesis of many pollysaccharides; sorting of Golgi products, which are then released in vesicles | |
| 489386816 | lysosome | a membranous sac of hydrolytic enzymes that an animal cell uses to digest macromolecules; breaks down ingested substances, cell macromolecules, and damaged organelles for recycling | |
| 489386817 | phagocytosis | a process in which amoebas and many other small protists eat by engulfing smaller organisms or other food particles | |
| 489386818 | food vacuole | a membranous sac formed by phagocytosis of microorganisms or particles to be used as food by the cell | |
| 489386819 | contractile vacuole | a membranous sac that helps move excess water out of certain freshwater protists | |
| 489386820 | central vacuole | a membranous sac in mature plant cells with diverse roles in reproduction, growth, and development; digestion, storage, waste disposal, water balance, cell growth, protection | |
| 489386821 | mitochondria | the sites of cellular respiration, the metabolic process that generates ATP by extracting energy from sugars, fats, and other fuels with the help of oxygen; bounded by double membrane; inner membrane has infoldings (cristae) | |
| 489386822 | chloroplasts | found in plants and algae and are the sites of photosynthesis; convert solar energy to chemical energy by absorbing sunlight and using it to drive the synthesis of organic compounds such as sugars from carbon dioxide and water; typically two membranes around fluid stroma, which contains membranous thylakoids stacked into grama (in plants) | |
| 489386823 | peroxisome | specialized metabolic compartment bounded by a single membrane; contains enzymes that transfer hydrogen to water, producing hydrogen peroxide as a by-product, which is converted to water by other enzymes in the peroxisome | |
| 489386824 | cristae | infoldings in the inner membrane of mitochondria | |
| 489386825 | mitochondrial matrix | the compartment of mitochondria enclosed by the inner membrane and containing enzymes and substrates for the citric acid cycle | |
| 489386826 | plastids | one of a family of closely related organelles that includes chloroplasts, chromopasts, and amyloplasts (leucoplasts); they are found in cells of photosynthetic organisms | |
| 489386827 | thylakoids | a flattened membranous sac inside a chloroplast; exist in an interconnected system in the chloroplast and contain the molecular machinery used to convert light energy to chemical energy | |
| 489386828 | granum | the stacks that thylakoids occur in | |
| 489386829 | stroma | fluid outside the thylakoids which contains the chloroplast DNA and ribosomes as well as many enzymes | |
| 489715737 | cytoskeleton | a network of fibers extending throughout the cytoplasm; plays a major role in organizing the structures and activities of the cell; composed of microtubules, microfilaments, and intermediate filaments; gives mechanical support to the cell and maintains its shape | |
| 489715738 | motor proteins | a protein that interacts with the cytoskeleton elements and other cell components, producing movement of the whole cell or parts of the cell | |
| 489715739 | microtubules | a hollow rod measuring 25 nm in diameter and 200 nm to 25um in length composed of tubulin proteins that make up part of the cytoskeleton in all eukaryotic cells and is found in cilia and flagella; each is a dimer, a molecule made up of two subunits; they shape and support the cell and also serve as tracks along which organelles equipped with motor proteins can move | |
| 489715740 | centrosome | structure present in the cytoplasm of animal cells, important during cell division; functions as a microtubule-organizing center; has two centrioles | |
| 489715741 | centrioles | a structure in the centrosome of an animal cell composed of a cylinder of microtubule triplets arranged in a 9 + 0 pattern | |
| 489715742 | flagella | a long cellular appendage specialized for locomotion; like motile cilia, eukaryotic flagella have a core with nine outer doublet microtubules ensheathed in an extension of the plasma membrane; prokaryotic flagella have a different structure | |
| 489715743 | cilia | a short cellular appendage containing microtubules; a motile cilium is specialized for locomotion and is formed from a core of nine outer doublet microtubules (the 9 + 2 arrangement) ensheathed in an extension of the plasmsa membrane; a primary cilium is usually nonmotile and plays a sensory and signaling role; it lacks the two inner microtubules (9 + 0 arrangement) | |
| 489715744 | basal body | a eukaryotic cell cell structure consisting of a 9 + 0 arrangement of microtubule triplets. it may organize the microtubule assembly of a cilium or flagellum and is structurally very similar to a centriole | |
| 489715745 | dyneins | in cilia and flagella, a large contractile protein extending from one microtubule doublet to the adjacent doublet. ATP hydrolysis drives changes in ___ shape that lead to bending of cilia and flagella | |
| 489715746 | microfilaments | a cable composed of actin proteins in the cytoplasm of almost every eukaryotic cell, making up part of the cytoskeleton and acting alone or with myosin to cause cell contraction; also known as actin filament | |
| 489715747 | actin | a globular protein that links into chains, two of which twist helically about each other, forming microfilaments (actin filaments) in muscle and other kinds of cells | |
| 489715748 | cortex | the outer region of cytoplasm in a eukaryotic cell, lying just under the plasma membrane, that has a more gel-like consistency than the inner regions, due to the presence of multiple microfilaments; in plants, ground tissue that is between the vascular tissue and dermal tissue in a root or eudicot stem | |
| 489715749 | pseudopodia | a cellular extension of amoeboid cells used in moving and feeding | |
| 489715750 | myosin | a type of protein filament that acts as a motor protein with actin filaments to cause cell contraction | |
| 489715751 | cytoplasmic streaming | a circular flow of cytoplasm, involving myosin and actin filaments, that speeds the distribution of materials within cells | |
| 489715752 | intermediate filaments | a component of the cytoskeleton that includes filaments intermediate in size (8-12 nm in diameter) between microtubules and microfilaments; more permanent fixtures of cells than the other two; especially important in reinforcing the shape of a cell and fixing the position of certain organelles | |
| 489715753 | cell wall | a protective layer external to the plasma membrane in the cells of plants, prokaryotes, fungi, and some protists. polysaccharides such as cellulose (in plants and some protists), chitin (fungi) and peptidoglycan (bacteria) are an important structural component of cell walls | |
| 489715754 | primary cell wall | in plants, a relatively thin and flexible layer first secreted by a young cell | |
| 489715755 | middle lamella | in plants, a thin adhesive extracellular material, primary pectins, found between the primary walls of adjacent young cells | |
| 489715756 | secondary cell wall | in plants, a strong and durable matrix often deposited in several laminated layers for cell protection and support | |
| 489715757 | extracellular matrix (ECM) | the substance in which animal cells are embedded, consisting of protein and polysaccharides synthesized and secreted by cells | |
| 489715758 | collagen | a glycoprotein in the extracellular matrix of animal cells that forms strong fibers, found extensively in connective tissue and bone; the most abundant protein in the animal kingdom | |
| 489715759 | proteoglycans | a glycoprotein consisting of a small core protein with many carbohydrate chains attached, found in the extracellular matrix of animal cells; may consist of up to 95% carbohydrate | |
| 489715760 | fibronectin | a glycoprotein that helps animal cells attach to the extracellular matrix | |
| 489715761 | integrins | in animal cells, a transmembrane receptor protein that interconnects the extracellular matrix and the cytoskeleton | |
| 489715762 | plasmodesmata | an open channel in the cell wall of a plant through which strands of cytosol connect from an adjacent cell | |
| 489715763 | tight junctions | the plasma membranes of neighboring cells are very tightly pressed against each other, bound together by specific proteins; prevent leakage of extracellular fluid across a layer of epithelial cells | |
| 489715764 | desmosomes | function like rivets, fastening cells together into strong sheets; attach muscle cells to each other in a muscle | |
| 489715765 | gap junctions | provide cytoplasmic channels from one cell to an adjacent cell and in this way are similar in their function to the plasmodesmata in plants; necessary for communication between cells in many types of tissues |
