| Term | Definition |
|---|
| Magnification | the ratio of an object's image to its real size |
| Resolving power | A measure of the clarity of the image; it is the minimum distance two points can be separated and still be distinguished as two separate points |
| Light microscopes (LMs) | Microscopes that use visible light to pass through the specimen and through glass lenses |
| Electron microscope | A microscope that instead of using light, focuses a beam of electrons through the specimen or on its surface |
| Scanning electron microscope (SEM) | an electron microscope commonly used for detailed study of the surface of the specimen |
| Transmission electron microscope (TEM) | an electron microscope commonly used to study the internal ultrastructure of cells |
| Cell fractionation | Goal to take cells apart; Uses a centrifuge that spins like a merry-go-round at various speeds |
| Ultracentrifuges | The most powerful centrifuge; can spin as fast as 130,000 revolutions per minute |
| Cytoplasm | The entire region between the nucleus and the plasma membrane |
| Cytosol | A semifluid substance within the membrane of cells; where organelles are found |
| Prokaryotic cell | No true nucleus, has circular chromosomes; Domains: Archae and Eubacteria |
| Eukaryotic cell | has a true nucleus, linear chromosomes; Domains: Eukarya |
| Nucleoid | Where the DNA is concentrated in the prokaryotic cell; no membrane separates this region from the rest of the cell |
| Plasma membrane | at the boundary of every cell, functions as a selective barrier; made of phospholipids and proteins |
| Nucleus | contains the chromatin, nucleolus, and nuclear envelope; contains most of the genes in the eukaryotic cell |
| Nuclear envelope | a double membrane enclosing the nucleus; perforated by pores |
| Chromatin | Within the nucleus; a fibrous material made of DNA and proteins |
| Chromosome | Chromatin fibers that coiled up, becoming thick enough to be discerned as separate structures; occurs when cell prepares to divide |
| nucleolus | a prominent structure within the nucleus; Ribosomal RNA is snthesized |
| Ribosome | particles made of ribosomal RNA and protein; the organelles that carry out protein synthesis (free/bound) |
| Endomembrane system | all the different membranes of the eukaryotic cell |
| vesicles | sacs made of membrane; transfer of membrane segments |
| Endoplasmic Reticulum (ER) | consists of a network of membranous tubules and sac; continuous with the nuclear envelope (smooth/rough) |
| Smooth ER | part of the ER where the cytoplasmic surface lacks ribosomes |
| Rough ER | part of the ER where cytoplasmic surface appears rough due to ribosomes attached |
| Glycoproteins | proteins that are covalently bonded to carbohydrates |
| centrioles | structure in animal cells composed of cylinders of microtubule triplets; a pair involved in animal celll division |
| Golgi Apparatus | A center of manufacturing, warehousing, sorting, and shipping; modifies the products of the ER |
| Cis face | the "receiving" side of the golgi apparatus; closer to the ER |
| Trans face | the "shipping" side of the golgi apparatus; further away from the ER |
| Lysosome | a membrane-bound sac of hydrolytic enzymes that the cell uses to digest macromolecules |
| Phagocytosis | A process that describes Amoebas/Protists eating by engulfing smaller organisms or other food particles |
| Autophagy | A process that describes lysosomes using their hydrolytic enzymes to recycle the cell's own organic material |
| Vacuoles/Vesicles | membrane-bound sacs within the cell (vacuoles larger than vesicles) |
| Food Vacuoles | formed by phacogytosis; pinches off of the plasma membrane and encloses a food particle |
| Contractile vacuoles | pumps excess water out of the cell (in many freshwater protists) |
| Central vacuole | The largest compartment in the plant cell; functions include storage, waste disposal, protection, and growth |
| Tonoplast | encloses the central vacuole; part of the endomembrane system |
| Peroxisome | a microbody containing enzymes that transfer hydrogen from various substrates to oxygen; produces hydrogen peroxide |
| Mitochondria | sites of cellular respiration (catabolic process that generates ATP); uses oxygen |
| intermembrane space | The narrow region between the inner and outer membranes of mitochondria |
| mitochondrial matrix | the compartment in mitochondria that is enclosed by the intermembrane space |
| cristae | inner foldings of the inner membrane of mitochondria |
| plastids | a family of closely related plant organelles (includes chloroplasts) |
| chloroplasts | sites of photosynthesis; found only in plants and algae |
| thylakoids | a membranous system in the form of flattened sacs inside of the chloroplasts |
| thylakoid space | the compartment within the stroma; contains the grana |
| granum | a stack of thylakoids (piled like poker chips) |
| stroma | the fluid outside of the thylakoids; cotains the chloroplast DNA, ribosomes, and enzymes |
| cytoskeleton | a network of fibers extending throughout the cytoplasm; gives the cell mechanical support, maintains shape, provides anchorage for organelles, motility |
| microtubules | the thickest of the three types of fibers that make up cytoskeleton; eukaryotic cells; hollow tube made from tubulin |
| microfilaments | the thinnest of the three types of fibers in cytoskeleton; two intertwined stands of actin |
| intermediate filaments | fibers with diameters in a middle range that make up cytoskeleton; fibrous proteins suercoiled into thicker cables |
| centrosome | a region near the nucleus where microtubules grow out from |
| cilia | locomotor appendages; usually occur in large numbers, have a back-and-forth motion |
| flagella | locomotor appendages; has an undulating motion |
| tubulin | a globular protein; constructs microtubules |
| dynein | a large contractile protein forming the side-arms of microtubule doublets in cilia and flagella |
| actin | a globular protein that links into chains, two of which twist helically about each other, forming microfilaments in muscle and other contractile elements in cells |
| myosin | a type of protein filament that interacts with actin filaments to cause cell contraction |
| plasmodesmata | porous holes between the plant cells; lets the cytoplasm become continous between the cells |
| cell wall | prevents the cell from bursting (not in animal cells) |
| Pilus | the primary function is for adhesion; sticky (in bacteria) |
| capsule | gelatenous covering; promotes adhesion; protects the bacteria |
| microvilli | helps increase surface area of cell; helps absorb nutrients from environment |
| cytoplasmic streaming | a circular flow of cytoplasm within cells; speeds the distribution of materials with the cell |
| primary cell wall | a relatively thin and flexible cell well secreted by young plant cells |
| middle lamella | a thin layer rich in sticky polysaccharides called pectins |
| secondary cell wall | a strong durable matrix often deposited in several laminated layers for plant cell protection and support |
Combine with other sets
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