Flashcards in deck_2562778 Deck (98):
attached toeither the inner or outer surfaces of the lipid bilayer
peripheral, or extrinsic, proteins
suggests that the plasma membrane is neither rigid norstatic in structure but is highly flexible and can change its shapeand composition through time
fluid mosaic model
protein molecules, penetratedeeply into the lipid bilayer,
integral, or intrinsic, proteins,
movement of solutes from an area of higher soluteconcentration to an area of lower solute concentration
results when a partition containing small holes isplaced in a stream of moving liquid
the processby which transport proteins mediate, or assist in, the movementof large, water-soluble molecules or electrically charged moleculesor ions across the plasma membrane.
literally means cell-eating( figure 3.23 ) and applies to endocytosis when solid particles areingested and phagocytic vesicles are formed.
internalization of substances,includes both phagocytosis and pinocytosis and refers to theuptake of material through the plasma membrane by the formationof a vesicle.
involves the active transport of an ion,such as sodium, out of a cell, establishing a concentration gradient,with a higher concentration of the ions outside the cell
secondary active transport
Thesesecretory vesicles then move to the plasma membrane, where themembrane of the vesicle fuses with the plasma membrane and thecontent of the vesicle is expelled from the cell.
– charge difference across the plasma membrane caused by the regulation of ion movement by cells-outside of plasma membrane is positively charged
surrounds the heart -contains pericardial fluid-located between the visceral pericardium and the parietal pericardium
surrounds each lung, which is covered by visceral pleura - lies between the visceral pleura and the parietal pleura and contains pleural fluid
limits the movement of phospholipids, providing stability to the plasma membrane
cell surface molecules that allow cells to identify one another or other molecules
allow cells to attach to other cells or to extracellular molecules
integral proteins that allow ions or molecules to move from one side of the plasma membrane to the other
one or more integral proteins arranged so that they form a tiny channel through the plasma membrane
channel proteins that are always open responsible for the permeability of the plasma membrane to ions when the plasma membrane is at rest
non-gated ion channel
channel proteins that can be open or closed
gated ion channel
open or close in response to chemical signals or ligands ( small molecules that bind to the proteins or glycoprotein)receptor on the surfacerequires a ligand (a chemical like acetycholine)
ligand-gated ion channel
open or close when there is a change in charge across the plasma membrane. -muscles or nerves
voltage-gated ion channel
integral membrane proteins that move ions or molecules from one side of the plasma membrane to the other-have specific binding sites to which ions or molecules attach on one side of the plasma membrane-change shape to move the bound ions or molecules to the other side of the plasma membrane, where they are released
Carrier proteins or transporters
transmembrane proteins that are not really open, but can flip-They do not have a channel-transport non-lipid soluble substances
the movement of one specific ion or molecule across the membrane
movement of two different ions or molecules in the same direction across the plasma membrane
movement of two different ions or molecules in opposite directions across the plasma membrane
transport proteins that move specific ions and molecules from one side of the plasma membrane to the other-movement is fueled by ATP breakdown
ATP powered pumps
proteins or glycoproteins in the plasma membrane with an exposed receptor site on the outer cell surface, which can attach to specific chemical signals
Receptor proteins -
catalyze chemical reactions on either the inner or the outer surface of the plasma membrane
is a carrier-mediated or channel-mediated process that moves substances into or out of cells from a higher to a lower concentration
Outer boundary of cells that controls entry and exit ofsubstances; receptor molecules function in intercellularcommunication; marker molecules enable cells torecognize one another
Lipid bilayer composed of phospholipids and cholesterolwith proteins that extend across or are embedded in eithersurface of the lipid bilayer
Support the cytoplasm and form centrioles, spindle fibers,cilia, and flagella; responsible for movement of structuresin the cell
Provide structural support to cells, support microvilli,responsible for cell movements
time between cell divisions. DNA isfound as thin threads of chromatin in the nucleus. DNAreplication occurs during the ___________Organelles, other than the nucleus, and centriolesduplicate during interphase.
chromatin condenses intochromosomes. Each chromosome consists of twochromatids joined at the centromere. The centriolesmove to the opposite ends of the cell, and the nucleolusand the nuclear envelope disappear. Microtubules formnear the centrioles and project in all directions. Some ofthe microtubules end blindly and are called astral fibers.Others, known as spindle fibers, project toward aninvisible line called the equator and overlap with fibersfrom opposite centrioles.
the chromosomes align in the center ofthe cell in association with the spindle fibers. Somespindle fibers are attached to kinetochores in thecentromere of each chromosome.
chromatids separate, and eachchromatid is then referred to as a chromosome. Thus,when the centromeres divide, the chromosome numberis double, and there are two identical sets ofchromosomes. The chromosomes, assisted by thespindle fibers, move toward the centrioles at each end ofthe cell.
migration of each set of chromosomes iscomplete. The chromosomes unravel to become lessdistinct chromatin threads. The nuclear envelope formsfrom the endoplasmic reticulum. The nucleoli form, andcytokinesis continues to form two cells.
division of the cytoplasm ofthe cell to produce two new cells.
the division of the nucleus into two nuclei,each of which has the same amount and type of DNA as the originalnucleus.
s the process by which two new strands of DNAare made, using the two existing strands as templates
DNA replication i
s a somewhat rounded, denseregion within the nucleus that lacks a surrounding membrane
the sites of protein synthesisEach is composed of a large subunit and a smaller one
The outer membrane of the nuclear envelope is continuous witha series of membranes distributed throughout the cytoplasm ofthe cell called
The interior spacesof those sacs and tubules of ER are called and areisolated from the rest of the cytoplasm.
composed of flattened,membranous sacs, containing cisternae, that are stacked on each other, like dinner platesa packaging and distribution center because it modifies,packages, and distributes proteins and lipids manufactured by the Rough and smooth endoplasmic reticula
are membrane-bound vesicles that pinchoff from the Golgi apparatus (see figure 3.33 ). They contain a variety of hydrolytic enzymes that function as intracellular digestion systems
digest the organelles of the cell that are no longer functional ina process called autophagia
are membrane-bound vesicles that are smaller than lysosomes.contain enzymesthat break down fatty acids and amino acids.hydrogen peroxide which can be toxic to the cell, is a by-product of that breakdown.
consist of large protein complexes,including several enzymes that break down and recycle proteinswithin the cell. are not surrounded by membranes. Theyare tunnel-like structures,
which is the substancelocated in the space formed by the inner membrane of mitochondria
specialized zone of cytoplasmclose to the nucleus, is the center of microtubule formation.
consists of a fluid portion, a cytoskeleton, andcytoplasmic inclusions.
supports the cell and holds the nucleus and other organelles in place. It is also responsible for cell movements, such as changes in cell shape and the movement of cell organelles.
is the study of the structural changesthat occur between conception and adulthood.
is the study of the external form of the bodyand its relation to deeper structures.
uses radiographs (x-rays), ultrasound, magnetic resonanceimaging (MRI), and other technologies to create picturesof internal structures (
study of structures that can be examinedwithout the aid of a microscope
is the condition in which the parts of an organismhave specific relationships to each other and the parts interactto perform specific functions.
is all of the chemical reactionstaking place in an organism. It includes an organism ’s ability tobreak down food molecules, which it uses as a source of energyand raw materials to synthesize its own molecules.
organism ’s ability to sense changesin its external or internal environment and adjust to thosechanges.
happens when cells increase in size or number, whichproduces an overall enlargement of all or part of an organism.
includes the changes an organism undergoesthrough time; it begins with fertilization and ends at death.
is change incell structure and function from generalized to specialized, andmorphogenesis
is change in the shape of tissues,organs, and the entire organism.
Component of negative f mechanism which monitors the value of a variable
negative-feedback mechanisms have three components: which receives information about the variable fromthe receptor,
negative f mechanism component which produces responses that change the valueof the variable.
refers to a person standing erect withthe face directed forward, the upper limbs hanging to the sides, andthe palms of the hands facing forward
body cavity– surrounded by the rib cage-separated from the abdominal cavity by the diaphragm- divided into right and left parts by a median partition called the mediastinum (middle wall)
contains the heart, the thymus, the trachea, the esophagus, and other structures, such as blood vessels and nerves
-enclosed by the abdominal muscles-contains the stomach, intestines, liver, spleen, pancreas, and kidneys.
encased by pelvic bones-where the urinary bladder, part of the large intestine, and the internal reproductive organs are housed
Pelvic cavity –
cover the organs of the trunk cavities and line the trunk cavities
Serous membranes -
parts of peritoneum that hold abdominal organs in place-provide a passageway for blood vessels and nerves to organs
organs found behind parietal peritoneum
changes in function, and in structure, caused by exercise.
water channel proteins, increase membranepermeability to water in some cell types, such as kidney cells
is a mediated transport process that requiresenergy provided by ATP (
means cell-drinking and is distinguishedfrom phagocytosis in that smaller vesicles are formed,
oxygen carbon dioxide and lipidstype of membrane transport mechanism
water moves from intestines to bloodtype of membrane transport mechanism
filtration in the kidneys allows removal of wastes materials in the bloodtype of membrane transport mechanism
glucose moves into muscle and fat cells through
ions such as sodium calcium and potassium type of membrane transport mechanism
Phagocytes ingest bacteriatype of membrane transport mechanism
Digestive enzymes, hormones, neurotransmitters, andglandular secretions are transported, and cell wasteproducts are eliminated.type of membrane transport mechanism
There is a concentration gradient for Na into intestinal epithelial cells. This gradient provides the energy for the symport of glucose. As Na enter the cell, down their concentrationfacilitated diffusion, glucose also enters the cell. In many cells, H are moved in the opposite direction of Na (antiport).type of membrane transport mechanism
secondary active transport
Genetic disorder that affects active transport of Cl into cells
Diffusing substance moves in the same direction as the transported substance
Diffusing substance moves in the opposite direction as the transported substance
When a specific substance binds to ther receptor molecule, endocytosis is triggered
Receptor mediated endocytosis
Membrane bound sacs that accumulate materials for release from the cell
Subunits of ribosomes formed in the
Subunits of ribosomes leave the nucleoli through