AP Biology: The Cell, Chapter 3 - Structure and Function of the Eukaryotic Cell
Lysosome
A membrane-bound organelle in the cytoplasm of most cells containing various hydrolytic enzymes that function in intracellular digestion.
Vacuole
A membrane-bound organelle in the cytoplasm of most cells, especially plant cells, containing water and dissolved substances such as salts, sugars, enzymes, and amino acids.
Contractile Vacuole
A membrane-surrounded vacuole that periodically fills with liquid, expands and then actively voids the contents to the outside of the organism.
Golgi Apparatus
A membranous system of cisternae and vesicles concerned with intracellular transport of membrane-bounded secretory proteins.
Golgi Apparatus
A membranous system of cisterns and vesicles located between the nucleus and the secretory pole or surface of a cell.
Golgi Apparatus
A membranous system of cisterns and vesicles located between the nucleus and the secretory pole or surface of a cell; concerned with the investment and intracellular transport of membrane-bounded secretory proteins.
Cytoskeleton
A network of MICROTUBULES and MICROFILAMENTS in the cytoplasm of cells which is thought to give the cell its characteristic shape; enables the movement of specific organelles within the cytoplasm .
Endomembrane System
A network of membranes inside and around a eukaryotic cell, related either through direct physical contact or by the transfer of membranous vesicles.
Golgi Apparatus
A network of stacked membranous vesicles, present in most living cells, that stores and modifies proteins and other macromolecules and transports them within the cell or excretes them from the cell.
Chloroplast
A plant cell inclusion body containing chlorophyll; occurs in cells of leaves and young stems. Site of photosynthesis in higher plants.
Mitochondria
A rodlike, threadlike, or granular organelle that functions in aerobic respiration and occurs in varying numbers in all eukaryotic cells.
Nucleus
A rounded or oval mass of protoplasm within the cytoplasm of a plant or animal cell; it is surrounded by a nuclear envelope that encloses euchromatin, heterochromatin, and one or more nucleoli, and undergoes mitosis during cell division.
Nucleolus
A rounded refractile body in the nucleus of most cells, which is the site of synthesis of ribosomal RNA, becoming enlarged during periods of synthesis and smaller during quiescent periods.
Nucleolus
A rounded refractile body in the nucleus of most cells, which is the site of synthesis of ribosomal RNA.
Lysosome
A sac-like structure is surrounded by a single-layered membrane which is impermeable and resistant to the enzymes inside; when the sac ruptures, the enzymes are released into a food vacuole produced by PHAGOCYTOSIS, thus enabling the breakdown of ingested materials.
Thylakoid
A saclike membrane in the chloroplasts of plant cells that is often arranged in stacks called grana and that is the site of the light reactions of photosynthesis.
Golgi Apparatus
A series of cell ORGANELLES consisting of a stack of membrane-lined vesicles; thought to have a storage role as well as enabling the assembly of simple molecules into more complex ones.
Endoplasmic Reticulum
A series of interconnected, flattened cavities continuous with the NUCLEAR MEMBRANE; can be covered with RIBOSOMES, referred to as rough ER, or ribosomes may be absent in which case the ER is known as smooth ER; associated with lipid synthesis.
Nucleolus
A small body in the nucleus of a cell that contains protein and RNA and is the site for the synthesis of ribosomal RNA and for the formation of ribosomal subunits.
Contractile Vacuole
A small fluid-filled cavity in the protoplasm of certain unicellular organisms; gradually increases in size and then collapses; its function is thought to be respiratory and excretory.
Lysosome
A small intracellular organelle occurring in the cytoplasm of most cells, containing various hydrolytic enzymes and normally involved in the process of localized intracellular digestion.
Thylakoid
A small membranous sac within a chloroplast of a plant.
Vacuole
A small space in the body enclosed by a membrane, usually containing fat, secretions, or cellular debris.
Vacuole
A small, clear region in the CYTOPLASM of a cell, sometimes surrounded by a membrane; may be used to store cell products or may serve an excretory function.
Nucleolus
A small, dense rounded body found in the nucleus of most cells;generates RIBOSOMES and is the site of the transcription of ribosomal RNA.
Nucleolus
A small, rounded mass within the cell nucleus where ribonucleoprotein is produced.
Nucleolus
A small, rounded mass within the cell nucleus where ribosomal ribonucleoprotein is produced; it is usually single, but there may be several not bound to membrane accessory nucleoli besides the principal one.
Mitochondria
A small, spherical to rod-shaped, membrane-bounded cytoplasmic organelle, the principal sites of ATP synthesis; contain DNA, RNA, and ribosomes; they replicate independently and synthesize some of their own proteins.
Ribosome
A sphere-shaped structure within the cytoplasm of a cell that is composed of RNA and protein and is the site of protein synthesis; often attached to the membrane of the endoplasmic reticulum.
Nucleus
A spheroid body within a cell, consisting of a thin nuclear membrane, organelles, one or more nucleoli, chromatin, linin, and nucleoplasm.
Nucleus
A spheroid body within a cell, contained in a double membrane, the nuclear envelope, and containing the chromosomes and one or more nucleoli.
Ribosome
A structure composed of RNA and protein, present in large numbers in the cytoplasm of living cells and serving as the site for assembly of polypeptides encoded by messenger RNA.
Thylakoid
A structure in the chloroplast of photosynthesizing cells; one of an interconnected stack, having a pigmented membrane that is the site of photosynthesis.
Endomembrane System
A system including the nuclear envelope, endoplasmic reticulum, Golgi apparatus, lysosomes, vesicles, vacuoles, and plasma membrane.
Ribosome
A tiny, mitten-shaped organelle occurring in great numbers in the cell cytoplasm and functioning as the site of protein.
Chloroplast
A type of PLASTID containing CHLOROPHYLL found within the cells of plant leaves and stems.
Peroxisome
A type of organelle present in most eukaryotic cells that carry out oxidative reactions, such as oxidation of alcohol in the liver.
Mitochondria
Intracellular (including intramuscular) organelles in which oxidative phosphorylation of ADP to ATP takes place: the essential 'power houses' of the cell.
Peroxisome
Membrane-bound cell organelles containing oxidative enzymes concerned in the detoxification of various molecules and in the breakdown of fatty acids to acetyl-CoA.
Nuclear Pores
Pores involved in the exchange of material between the nucleus and the cytoplasm.
Endomembrane System
Regulates protein traffic, and preforms metabolic function cells; includes the nuclear envelope, endoplasmic reticulum, Golgi apparatus, lysosomes, vesicles, vacuoles, and plasma membrane.
Nuclear Envelope
The double membrane at the boundary of the nucleoplasm; it has regularly spaced pores covered by a disclike nuclear pore complex.
Nuclear Envelope
The double membrane, with perforations (pores), surrounding a cell nucleus.
Golgi Apparatus
The small membranous structures found in most cells, composed of various elements associated with the formation of carbohydrate side chains of glycoproteins, mucopolysaccharides, and other substances.
Smooth Endoplasmic Reticulum
Parts of the endoplasmic reticulum involved in the synthesis of steroid hormones, and of other lipids; storing Ca++ ions in muscle cells, and detoxifying drugs and poisons from the body.
Smooth Endoplasmic Reticulum
Parts of the endoplasmic reticulum to which ribosomes are NOT attached on the cytoplasmic side.
Rough Endoplasmic Reticulum
Parts of the endoplasmic reticulum to which ribosomes are attached on the cytoplasmic side.
Contractile Vacuole
A cavity formed by the accumulation of fluid; after increasing for a time it empties itself externally by a sudden contraction; it functions as an osmoregulatory mechanism for water balance, especially in freshwater protozoans.
Eukaryotic Cell
A cell containing a true nucleus bounded by a nuclear membrane within which lie the chromosomes; also contain many membrane-bound organelles in which cellular functions are performed.
Peroxisome
A cell organelle containing a large number of enzymes, including catalase and oxidase, that break down long-chain fatty acids and other organic molecules; the hydrogen peroxide produced by these reactions is also broken down within the organelle.
Eukaryotic Cell
A cell that contains a distinct membrane-bound nucleus and by the occurrence of DNA transcription inside the nucleus and protein synthesis in the cytoplasm.
Eukaryotic Cell
A cell which contains a membrane-bound nucleus with chromosomes of DNA and proteins; cell division involving a form of mitosis in which mitotic spindles are involved; mitochondria are present, and, in photosynthetic species, plastids are found.
Eukaryotic Cell
A cell which contains a well defined nucleus with a nuclear membrane in which the genetic material is carried in the chromosomes.
Eukaryotic Cell
A cell which contains membrane-bound organelles, such as mitochondria, chloroplasts, lysosomes, and the Golgi apparatus.
Eukaryotic Cell
A cell which has a true nucleus bounded by a nuclear membrane, contains the chromosomes, and divides by mitosis.
Vacuole
A clear space in the substance of a cell, sometimes degenerative in character, sometimes surrounding an engulfed foreign body and serving as a temporary cell stomach for the digestion of the body.
Vacuole
A clear space in the substance of a cell; may stem from a degenerative process, or it may serve the cell as a temporary cell stomach for the digestion of a foreign body inclusion.
Cytoskeleton
A complex network of ACTIN filaments within the nucleated cell; has contractile properties and can alter the shape, size and even movement, of the cell.
Cytoskeleton
A conspicuous internal reinforcement in the cytoplasm of a cell, consisting of tonofibrils, filaments of the terminal web, and other microfilaments.
Lysosome
A cytoplasmic membrane-bound vesicle (primary lysosome) and containing a wide variety of glycoprotein hydrolytic enzymes active at an acid pH; serves to digest exogenous material, such as bacteria.
Lysosome
A cytoplasmic membrane-bound vesicle containing a wide variety of glycoprotein hydrolytic enzymes active at an acid pH; serves to digest exogenous material, such as bacteria, as well as effete organelles of the cells.
Lysosome
A cytoplasmic organelle of EUKARYOTE cells that contains hydrolytic enzymes and is thought to be produced by the GOLGI APPARATUS; act as the digestive system of the cell.
Lysosome
A cytoplasmic, membrane-bound particle that contains hydrolytic enzymes that function in intracellular digestive processes.
Nuclear Envelope
A double membrane that surrounds the nucleus of a eukaryotic cell.
Thylakoid
A flattened membrane sac inside the chloroplast, used to convert light energy into chemical energy.
Cristae
A fold in the inner membrane of a MITOCHONDRION enclosing a cisterna-like space inside the fold, on which the electron-transport reactions of AEROBIC RESPIRATION take place.
Catalase
A heme-containing enzyme that specifically catalyzes the decomposition of hydrogen peroxide and is found in almost all cells except certain anaerobic bacteria.
Catalase
A hemoprotein catalyzing the decomposition of hydrogen peroxide to water and oxygen (2H2O2 → O2 + 2H2O).
Catalase
A hemoprotein enzyme that specifically catalyzes the decomposition of hydrogen peroxide and is found in almost all cells except certain anaerobic bacteria.
Endoplasmic Reticulum
A highly convoluted membrane system within cells to which RIBOSOMES attach themselves for protein synthesis; the site of many other cell metabolic reactions.
Endoplasmic Reticulum
A membrane network within the cytoplasm of cells involved in the synthesis, modification, and transport of cellular materials.
Contractile Vacuole
A membrane-bound organelle found in certain protists that pumps fluid in a cyclical manner from within the cell to the outside by alternately filling and then contracting to release its contents at various points on the surface of the cell; functions in maintaining osmotic equilibrium.
Catalase
An ENZYME found in the microbodies (peroxisomes) of cells and that promotes the reaction in which two molecules of hydrogen peroxide are converted to two molecules of water and one molecule of oxygen.
Catalase
An enzyme found in living cells that catalyzes the decomposition of hydrogen peroxide, a potentially harmful oxidizing agent, into water and oxygen.
Endoplasmic Reticulum
An extensive network of membrane-enclosed tubules in the cytoplasm of a cell.
Endoplasmic Reticulum
An extensive network of membrane-enclosed tubules in the cytoplasm of cells. The structure functions in the synthesis of proteins and lipids and in the transport of these metabolites within the cell.
Golgi Apparatus
An intracellular transport system formed of channels and vesicles facilitating modification, storage and packaging of intracellular products, secretory proteins and lysozomal enzymes prior to their release from the cell.
Mitochondria
An organelle bounded by two sets of membranes, a smooth outer one and an inner one that is arranged in folds, or cristae, that extend into the interior of the mitochondrion, called the matrix.
Nucleus
An organelle of eukaryotic cells that is bounded by a NUCLEAR MEMBRANE and contains the chromosomes whose genes control the structure of proteins within the cell.
Endoplasmic Reticulum
An organelle of nearly all higher plant and animal cells, consisting of a system of membrane-bound cavities in the cytoplasm, occurring in two types: granular or rough-surfaced, bearing large numbers of ribosomes on its outer surface, and agranular or smooth-surfaced.
Ribosome
Any of numerous minute particles in the cytoplasm of cells, either free or attached to the endoplasmic reticulum, that contain RNA and protein and are the site of protein synthesis
Nuclear Pores
Any of the nonrandomly distributed, octagonal orifices in the nuclear envelope.
Nucleolus
Any one of the small, dense structures composed largely of ribonucleic acid that are situated within the cytoplasm of cells; essential in the formation of ribosomes that synthesize cell proteins.
Nuclear Pores
Microscopic openings in the nuclear membrane; control the movement of substances between the nucleus and the cytoplasm.
Cristae
Numerous narrow transverse infoldings of the inner membrane of a mitochondrion.
Cristae
One of the inward projections or folds of the inner membrane of a mitochondrion.
Lysosome
One of the minute bodies occurring in many types of cells, containing various hydrolytic enzymes and normally involved in the process of localized intracellular digestion.
Mitochondria
Ovoid cell organelles, formed of double membranes, the inner layer of which is extensively folded into cristae; site of oxidative phosphorylation, citric acid cycle, electron transport chain and adenosine triphosphate synthesis
Rough Endoplasmic Reticulum
Parts of the endoplasmic reticulum involved in the biosynthesis of proteins for export to the outside of the cell and enzymes to be incorporated into cellular organelles such as lysosomes.
Mitochondria
Spherical or rod shaped parts of the cell; contain genetic material (DNA and RNA) and are responsible for converting food to energy.
Nucleus
The central controlling body within a living cell, usually a spheric unit enclosed in a membrane and containing genetic codes for maintaining life systems of the organism and for issuing commands for growth and reproduction.
Nuclear Envelope
The condensed double layer of lipids and proteins enclosing the cell nucleus and separating it from the cytoplasm.
Nuclear Envelope
The condensed double layer of lipids and proteins enclosing the cell nucleus and separating it from the cytoplasm; its two concentric membranes, inner and outer, are separated by a perinuclear space.
Cytoskeleton
The internal framework of a eukaryotic cell, composed of protein filaments that provide structural support and drive the movement of the cell and its internal components, typically divided into microfilaments, intermediate filaments, and microtubules.
Cytoskeleton
The microtubules and the filaments (thin, intermediate, and thick) that serve as supportive cytoplasmic elements to stiffen cells or to organize the location and movement of intracellular organelles.
Endoplasmic Reticulum
The network of cytoplasmic tubules or flattened sacs (cisternae) with (rough ER) or without (smooth ER) ribosomes on the surface of their membranes in eukaryotes.
Endoplasmic Reticulum
The network of cytoplasmic tubules or flattened sacs with or without ribosomes on the surface of their membranes.
Nucleus
The organelle in a eukaryotic cell which contains the genomic information (DNA), replicative and transcriptional machinery (RNA), and binding proteins needed to copy the genomic information and encode the structural and functional proteins required for cell activity.
Chloroplast
The photosynthetic unit of a plant cell, containing all the chlorophyll.