Terms : Hide Images
| 1028709897 | Light microscope (LM) | Optical instrument with lenses that refract (bend) visible light to magnify images and project them into the viewer's eye or onto photographic film. These can be used to study live specimens, but they only magnify about a thousand times. | |
| 1028709898 | Magnification | The increase in the apparent size of an object. | |
| 1028709899 | Resolution | A measure of the clarity of an image OR the ability of an optical instrument to show objects as separate. | |
| 1028709900 | Cell theory | The theory that all living things are composed of cells and that all cells come from other cells. | |
| 1028709901 | Electron microscope (EM) | An instrument that focuses an electron beam through (or onto the surface of) a specimen. It has electromagnets as lenses and achieves a thousandfold greater resolution than a light microscope, but isn't that great for studying live specimens. | |
| 1028709902 | Scanning electron microscope | Microscope that uses an electron beam to study (scan) the surface architecture of a cell (or other specimen). Produces images that look 3D. | |
| 1028709903 | Transmission electron microscope | Microscope that uses an electron beam to study the internal structure of thinly sectioned specimens. | |
| 1028709904 | Prokaryotic cell | A type of cell lacking a membrane-enclosed nucleus and other membrane-enclosed organelles. Found in bacteria and archaea. | |
| 1028709905 | Eukaryotic cell | A type of cell that has a membrane-enclosed nucleus and other membrane-enclosed organelles. Found in protists, fungi, plants, and animals. | |
| 1028709906 | Features of cells | - Bound by a plasma membrane - Genes made of DNA as hereditary material - Contain ribosomes | |
| 1028709907 | Plasma membrane | A thin layer of lipids and proteins that sets cell off from surroundings and acts as a selective barrier to passage of ions and molecules into and out of the cell. Consists of a phospholipid bilayer in which are embedded molecules of protein and cholesterol. | |
| 1028709908 | Ribosomes | Cell organelles consisting of RNA and protein organized into two subunits and functioning as the site of protein synthesis in cytoplasm. Constructed in the nucleolus. | |
| 1028709909 | Nucleotide region | A region in a prokaryotic cell where the DNA is coiled. | |
| 1028709910 | Cell wall | A protective layer external to the plasma membrane in plant cells, bacteria, fungi, and some protists. It protects and maintains the shape of the cell. | |
| 1028709911 | Capsule | A sticky layer that surrounds the bacteria cell wall, protects the cell surface, and sometimes helps glue the cell to surfaces. | |
| 1028709912 | Pilus | Short projections on the surface of a prokaryotic cell that helps it to attach to surfaces. | |
| 1028709913 | Cytoplasm | Everything inside a eukaryotic cell between the plasma membrane and nucleus. It consists of a semifluid medium and organelles. | |
| 1028709914 | Organelles | Structure with a specialized function in a cell. | |
| 1028709915 | Cellular metabolism | The chemical activities of cells. | |
| 1028709916 | Differences in eukaryotic plant cells | - Rigid, thick cell wall (like fungi and many protists) with cellulose. - Chloroplast (where photosynthesis occurs) - Central vacuole (a compartment that stores water and chemicals) | |
| 1028709917 | Nucleus | The genetic control center of the eukaryotic cell. Contains DNA and controls the actions of the cell by directing protein synthesis. | |
| 1028709918 | Chromatin | Combination of DNA and proteins that constitutes chromosomes. Sometimes used to refer to diffuse and very extended form taken by chromosomes when a cell isn't dividing. | |
| 1028709919 | Chromosome | A threadlike, gene-carrying structure found in the nucleus of a eukaryotic cells and most visible during mitosis and meiosis. Also the main gene-carrying structure of prokaryotic cells. | |
| 1028709920 | Nuclear envelope | A double membrane perforated with pores that encloses the nucleus. | |
| 1028709921 | Nucleolus | A structure within a eukaryotic cell nucleus where ribosomal RNA is made and assembled with proteins to make ribosomal subunits. Consists of parts of chromatin DNA, RNA transcribed from that DNA, and proteins imported. | |
| 1028709922 | Endomembrane system | A network of membranous organelles that partition the cytoplasm of a eukaryotic cells into functional compartments. Some membranes are physically connected, others are related by a transfer of membrane segments by tiny vesicles. | |
| 1028709923 | Vesicles | Sacs made of membrane in the cytoplasm of a eukaryotic cell. | |
| 1028709924 | Endoplasmic reticulum (ER) | Extensive membranous organelles in a eukaryotic cell, continuous with the outer nuclear membrane and composed of ribosome-studded (rough) and ribosome-free (smooth) regions. | |
| 1028709925 | Smooth ER | A network of interconnected membranous tubules in the cytoplasm of a eukaryotic cell. Lacks ribosomes. The enzymes embedded in the membrane function in the synthesis of certain kinds of molecules, like lipids. Also serves as storage for calcium ions. | |
| 1028709926 | Rough ER | A network of interconnected membranous sacs in the cytoplasm of a eukaryotic cell. Studded with ribosomes that make membrane and secretory proteins. Constructs membrane from phospholipids and proteins. They modify proteins that will be secreted or transported to other organelles. | |
| 1028709927 | Secretory protein | A protein (like an antibody) that is secreted by a cell. | |
| 1028709928 | Synthesis, modification, and packing of a secretory protein | 1) As a polypeptide is synthesized by an attached ribosome, it passes into the ER, where it is folded into its 3D shape. 2) Short chains of sugars link to it, making it into a glycoprotein. 3) The ER packs it into a transport vesicle. | |
| 1028709929 | Glycoprotein | A macromolecule consisting of one or more polypeptides linked to short chains of sugar. | |
| 1028709930 | Transport vesicle | A tiny membranous sac in a cell's cytoplasm carrying molecules produced by the cell. Buds from the ER or Golgi eventually fuses with another membranous organelle or plasma membrane, releasing the contents. | |
| 1028709931 | Golgi apparatus | An organelle in eukaryotic cells that consist of stacks of membranous sacs that modify, store, and ship ER products. | |
| 1028709932 | Lysosome | A digestive organelle in eukaryotic cells that contains hydrolytic enzymes that digest the cell's food and wastes. The membrane encloses a compartment where digestive enzymes are provided with an acidic environment, safe from cytoplasm. These have digestive functions, they serve as recycling centers for cells, and play vital roles in embryonic development. | |
| 1028709933 | Vacuoles | Membrane-enclosed sacs that are part of the endomembrane system of a eukaryotic cell. They have many diverse functions. | |
| 1028709934 | Central vacuole | A membrane-enclosed sac occupying most of the interior of a mature plant cell. It has diverse roles in reproduction, growth, and development. | |
| 1028709935 | Chloroplasts | Organelles found in plants and photosynthetic protists. Enclosed by two concentric membranes, chloroplasts absorb sunlight and use it to power the synthesis of organic food molecules (sugars). | |
| 1028709936 | Stroma | A thick fluid found in the inner membrane of a chloroplast. This is where sugars are made by enzymes of the Calvin cycle. | |
| 1028709937 | Granum | A stack of hollow disks formed of thylakoid membrane in a chloroplast. They are sites where light energy trapped by chlorophyll and converted to chemical energy during the light reactions of photosynthesis. The plural is "grana." | |
| 1028709938 | Mitochondria | "Powerhouse" of the cell. Organelles in eukaryotic cells where cellular respiration occurs. Enclosed by two concentric membranes, they are where most of a cell's ATP is made. The singular is "mitochondrion." | |
| 1028709939 | Mitochondrial matrix | The fluid in the inner membrane of a mitochondrion. | |
| 1028709940 | Cristae | The folds in the intermembrane space of a mitochondrion. Enzyme molecules that make ATP are embedded in them. | |
| 1028709941 | Cytoskeleton | Meshwork of fine fibers in the cytoplasm of a eukaryotic cell; includes microfilaments, intermediate filaments, and microtubules. It provides structural support and cell movement, as well as regulating activities. | |
| 1028709942 | Microfilaments | The thinnest of the protein fibers in the cytoskeleton, they are solid helical rods composed of the globular protein actin. (Helps with moving, changing shape.) | |
| 1028709943 | Intermediate filaments | The medium-sized, ropelike protein fibers of the cytoskeleton. (They reinforce shape and anchor organelles.) | |
| 1028709944 | Microtubules | The thickest of the protein fibers in the cytoskeleton, they are straight, hollow tubes made of the globular protein tubulin. (Basis of structure and movement of cilia and flagella.) | |
| 1028709945 | Cilia | Short appendages that propel some protists through water and move fluids across the surface of many tissue cells in animals with coordinated movements. | |
| 1028709946 | Flagella | Long surface projections that propel cells with a whiplike motion.The singular is "flagellum." | |
| 1028709947 | Basal body | A eukaryotic cell organelle consisting of a 9+0 arrangement of microtubule triplets; they may organize microtubule assembly of cilia/flagella. They are structurally similar to centrioles. | |
| 1028709948 | Centriole | A structure in an animal cell composed of microtubule triplets in a 9+0 pattern, much like basal bodies. Animal cells have pairs of these within centrosomes. | |
| 1028709949 | Plasmodesmata | Open channels in the cell walls of plants through which strands of cytoplasm connect from adjacent walls. | |
| 1028709950 | Extracellular matrix | The substance in which the cells of an animal tissue are embedded; consists of proteins and polysaccharides. They help regulate cell behavior. | |
| 1028709951 | Cell junctions | How adjacent cells in animal tissues are connected. 1) TIGHT JUNCTIONS (Form a leak-proof sheet.) 2) ANCHORING JUNCTIONS (Connects tissue cells to other tissue cells or the extracellular matrix and allows materials to pass from cell to cell.) 3) GAP JUNCTIONS (A channel through which water and other small molecules can pass through freely.) | |
| 1028709952 | Micrograph | A photograph taken through a microscope. | |
| 1028709953 | Resolution | A measure of the clarity of an image | |
| 1028709954 | Prokaryotic flagellum | A long surface projection that propels a prokaryotic cell through its liquid environment; totally different from the flagellum of a eukaryotic cell. | |
| 1028709955 | Lysosomal storage diseases | A hereditary disorder associated with abnormal lysosomes, where the sufferer is missing one of the lysosomal digestive enzymes. | |
| 1028709956 | Intermembrane space | One of the two fluid-filled internal compartments of the mitochondrion, the narrow region between the inner and outer membranes. | |
| 1028709957 | Dynein arm | A protein extension from a microtubule doublet in a cilium or flagellum; involved in energy conversions that drive the bending of cilia and flagella. | |
| 1028709958 | Tight junction | A junction that binds tissue cells together in a leakproof sheet. | |
| 1028709959 | Anchoring junction | A junction that connects tissue cells to each other (or to an extracellular matrix) and allows materials to pass from cell to cell. | |
| 1028709960 | Communication junction | A channel between adjacent tissue cells through which water and other molecules pass freely. |
