Anatomy And Physiology By Kenneth S. Saladin 4Th Edition - Chapter 03 - Bscc2093

Front 1

Fluid-Mosaic Model

Back 1

The current theory of the structure of a plasma membrane, depicting it as a bilayer of phospholipids with embedded proteins, many of which are able to move about in the lipid film

Front 2

Mitochondrion

Back 2

An organelle specialized to synthesize ATP, enclosed in a double unit membrane with infoldings of the inner membrane called cristae.

Front 3

Pinocytosis

Back 3

"Cell Drinking" - A form of endocytosis in which the plasma membrane sinks inward and imbibes droplets of extracelluar fluid or specific molecules concentrated from that fluid.

Front 4

Ameboid Movement

Back 4

Movement of a cell by means of pseudopods, in a manner similar to that of an ameba; seen in leukocytes and some macrophages.

Front 5

Cellular Membrane

Back 5

Any unit membrane enclosing a cell or organelle.

Front 6

Axoneme

Back 6

The core of microtubules, usually in a "9 + 2" array, at the center of a cilium or flagellum.

Front 7

Carrier-Mediated Transport

Back 7

A process of transporting materials through a cellular membrane that involves reversible binding to a membrane protein.

Front 8

Cilium

Back 8

A hairlike process, with an axoneme, projecting from the apical surface of an epithelial cell; usually motile and serving to propel matter across the surface of an epithelium but sometimes serving sensory roles.

Front 9

flagellum

Back 9

A long, motile, usually single hairlike extension of a cell; the tail of a sperm cell is the only functional flagellum in humans.

Front 10

Apical Surface

Back 10

The uppermost surface of an epithelial cell, usually esposed to the lumen of an organ.

Front 11

Dextrose

Back 11

The D-isomer of glucose; the only form of glucose with a normal role in physiology.

Front 12

Endocytosis

Back 12

Any process in which a cell forms vesicles from its plasma membrane and takes in large particles, molecules, or droplets of extracellular fluid; for example, phagocytosis and pinocytosis.

Front 13

Gate

Back 13

A protein channel in a unit membrane that can open or close in response to chemical or electrical stimuli, this controlling when substances are allowed to pass through the membrane.

Front 14

Hypertonic

Back 14

Having higher osmotic pressure than human cells or some other reference solution and tending to cause osmotic shrinkage of cells.

Front 15

Fluid-Phase Pinocytosis

Back 15

A form of endocytosis in which the cell imbibes droplets of extracellular fluid without modifying its composition or concentration.

Front 16

Intracellular

Back 16

Within a cell.

Front 17

Concentration Gradient

Back 17

A gradual change in chemical conentration from one point to another.

Front 18

G Protein

Back 18

A protein of the plasma membrane that is activated by a membrane receptor and, in turn, opens an ion channel or activates an intracellular physiological response; important in linking ligand-receptor binding to second messenger systems.

Front 19

Ligand-Gated Channel

Back 19

A channel protein in a plasma membrane that opens or closes when a ligand binds to it, enabling the ligand to determine when substances can enter or leave the cell.

Front 20

Carrier

Back 20

A protein in a cellular membrane that performs carrier-mediated transport.

Front 21

Light Microscope

Back 21

A microscope that produces images with visible light.

Front 22

Osmosis

Back 22

The net diffusion of water through a selectively permeable membrane.

Front 23

Osmotic Pressure

Back 23

The amount of pressure that would have to be applied to one side of a selectively permeable membrane to stop osmosis; proportional to the concentration of nonpermeating solutes on that side and therefore serving as an indicator of solute concentration.

Front 24

Golgi Vesicle

Back 24

A membrane-bound vesicle pinched from the golgi complex, containing its chemical product; may be retained in the cell as a lysosome or become a secretory vesicle that releases the product by exocytosis.

Front 25

Channel Protein

Back 25

A protein in the plasma membrane that has a pore through it for the passage of materials between the cytoplasm and extracellular fluid.

Front 26

Centriole

Back 26

An organelle composed of two short perpendicular cylinders of microtubules; origin of the mitotic spindle.

Front 27

Antiport

Back 27

An active transport carrier that moves two or more solutes in opposite directions through a cellular membrane; for example, the Na+ K+ pump.

Front 28

Microvillus

Back 28

An outgrowth of the plasma membrane that increases the surface area of a cell and functions in absorption and some sensory processes; distinguished from cilia and flagella by its smaller size and lack of an axoneme.

Front 29

Microtubule

Back 29

An intracellular cylinder composed of the protein tubulin, forming the axonemes of cilia and flagella and part of the cytoskeleton.

Front 30

Integral Protein

Back 30

A protein that extends through a plasma membrane and contacts both the extracellular and intracellular fluid.

Front 31

Actin

Back 31

A filamentous intracellular protein that provides cytoskeletal support and interacts with other proteins, especially myosin, to cause cellular movement; important in muscle contraction, ciliary and flagellar beating, and membrane actions such as phagocytosis, amoeboid movement, and cytokinesis.

Front 32

Nucleus

Back 32

A cellular organelle containing DNA and surrounded by a double unit membrane.

Front 33

Phagocytosis

Back 33

A form of endocytosis in which a cell surrounds a foreign particle with pseudopods and engulfs it, enclosing it in a cytoplasmic vesicle called a phagosome.

Front 34

Pseudopod

Back 34

A temporary cytoplasmic extension of a cell used for locomotion and phagocytosis.

Front 35

Reticular Fiber

Back 35

A fine, branching collagen fiber coated with glycoprotein, found in the stroma of lymphatic organs and some other tissues and organs.

Front 36

Endoplasmic Reticulum

Back 36

An extensive system of interconnected cytoplasmic tubules or channels; classified as Rough ER or Smooth ER depending on the presence or absence of ribosomes on its membrane.

Front 37

Active Transport

Back 37

The movement of a solute through a cellular membrane, against its concentration gradient, involving a carrier protein that expends ATP.

Front 38

Facilitated Diffusion

Back 38

The proess of transporting a chemical through a cellular membrane, down its concentration gradient, with the aid of a membrane carrier that does not consume ATP; enables substances to diffuse through the membrane that would do so poorly, or not at all, without a carrier.

Front 39

Filtrate

Back 39

A fluid formed by filtration.

Front 40

Filtration

Back 40

A process in which hydrostatic pressure forces a fluid through a selectively permeable membrane.

Front 41

Cuboidal

Back 41

A cellular shape that is roughly like a cube or in which the height and width are about equal.

Front 42

Cytoplasm

Back 42

The contents of a cell between its plasma membrane and its nuclear envelope, consisting of cytosol, organelles, inclusions, and the cytoskeleton.

Front 43

Gradient

Back 43

A difference or change in any variable, such as pressure or chemical concentration, from one point in space to another; provides a basis for molecular movements such as gas exchange, osmosis, and facilitated diffusion.

Front 44

Inclusion

Back 44

Any visible object in the cytoplasm of a cell other than an organelle or cytoskeletal element; usually a foreign body or a stored cell product, such as a virus, dust particle, lipid droplet, glcogen granule, or pigement.

Front 45

Intracellular Fluid

Back 45

The fluid contained in the cells; one of the major fluid compartments.

Front 46

Endothelium

Back 46

A simple squamous epithelium that lines the lumens of the blood vessels, heart, and lymphatic vessels.

Front 47

Organelle

Back 47

Any structure within a cell that carries out one of its metabolic roles, such as mitochondria, centrioles, endoplasmic reticulum, and the nucleus; an intracellular structure other than the cytoskeleton and inclusions.

Front 48

Receptor-Mediated Pinocytosis

Back 48

A form of endocytosis in which certain molecules in the extracellular fluid bind to receptors in the plasma membrane, these receptors become gathered togther, the membrane sinks inward at that point, and the molecules become incorported into vesicles in the cytoplasm.

Front 49

Base

Back 49

A chemical that binds protons from solution; a proton acceptor.

Front 50

Second Messenger

Back 50

A chemical that is produced within a cell or that enters a cell in response to the binding of a messenger to a membrane receptor and that triggers a metabolic reaction in the cell.

Front 51

Selectively Permeable Membrane

Back 51

A membrane that allows some substances to pass through while excluding others, i.e. the plasma membrane and dialysis membranes.

Front 52

Golgi Complex

Back 52

An organelle composed of several parallel cisternae, somewhat like a stack of saucers, that modifies and packages newly synthesized proteins and synthesizes carbohydrates.

Front 53

Dyenein

Back 53

A motor protein involved in the beating of cilia and flagella and in the movement of molecules and organelles within cells, as in retrograde transport in a nerve fiber.

Front 54

Symport

Back 54

A carrier protein that moves two solutes simultaneously through a plasma membrane in the same direction, such as the sodium-dependent glucose transporter of the small intestine.

Front 55

Hypotonic

Back 55

Having a lower osmotic pressure than human cells or some other reference solution and tending to cause osmotic swelling and lysis of cells.

Front 56

Secondary Active Transport

Back 56

A mechanism in which solutes are moved through a plasma membrane by a carrier that does not itself use ATP but depends on a concentration gradient established by an active transport pump elsewhere in the cell. Also called cotransport.

Front 57

Transmission Electron Microscope

Back 57

A microscope that uses an electron beam in place of light to form high-resolution, two-dimensional images of ultrathin slices of cells or tissues; capable of extremely high magnification.

Front 58

Unit membrane

Back 58

Any membrane composed of a bilayer of phospholipids and embedded proteins. A single unit membrane comprises the plasma membrane and encloses many organelles of a cell, whereas double unit membranes enclose the nucleus and mitochondria.

Front 59

Bulk Transport

Back 59

The movement of particles or fluid droplets through the plasma membrane by the process of endocytosis or exocytosis.

Front 60

Cisterna

Back 60

A fluid-filled space or sac, such as the cisterna chyli of the lymphatic system and a cisterna of the endoplasmic reticulum or golgi complex.

Front 61

Cytosol

Back 61

A clear, featureless, gelatinous colloid in which the organelles and other internal structures of a cell are embedded.

Front 62

Fusiform

Back 62

Spindle-shaped, elongated, thick in the middle, and tapered at both ends, such as the shape of a smooth muscle cell or a muscle spindle.

Front 63

Hydrostatic pressure

Back 63

The physical force generated by a liquid such as blood or tissue fluid, as opposed to osmotic and atmospheric pressures.

Front 64

Cytoskeleton

Back 64

A system of protein microfilaments, intermediate filaments, and microtubules in a cell, serving in physical support, cellular movement, and the routing of molecules and organelles to their destinations within the cell.