The study of cellular structure and function.
All human structure and function are the result of ________activity.
A cell is enclosed in a____________and usually contains one nucleus.
The___________is everything between the plasma membrane and nucleus.
The clear fluid inside of the cell.
Fluid external to the cell.
The plasma membrane is made of _________and protein.
The most abundant lipid molecules in the membrane are ________________, which form a bilayer with their hydrophilic heads facing the ICF and ECF.
Membrane proteins that are embedded in the lipid bilayer and extend all the way through it.
Membrane proteins that cling to only one face of the lipid bilayer.
Membrane proteins serve as receptors, second messenger systems, enzymes, ion channels, carriers, cell-identity markers and ______________molecules.
Channel proteins are called_______________ if they can open and close.
Gates are called ligand-regulated, voltage-regulated, or mechanically regulated depending on whether they open and close in response to _____________, voltage changes across a membrane, or mechanical stress.
____________ systems are systems for generating an internal cellular signal in response to an external one.
When certain extracellular signaling molecules bind to a membrane receptor it forms the second messenger_____________.
All cells are covered with a _______________, a layer of carbohydrate molecules bound to membrane lipids and proteins.
Functions in immunity and other forms of protection, cell adhesion, fertilization, and embryonic development, among other roles.
Tiny surface extensions of the plasma membrane that increase a cells surface area and sometimes play a sensory role.
Long, hairlike surface extensions with a central axoneme, composed of a 9+2 arrangement of microtubules.
Some_________are stationary and sensory in function, and some are motile and propel substances across epithelial surfaces.
A long, solitary, whiplike extension of the cell surface. The only one that functions humans is the sperm tail.
The plasma membrane is ____________permeable.
The movement of fluid through a membrane under a physical force such as blood pressure, while the membrane holds back relatively large particles.
The spontaneous net movement of particles from a place of high concentration to low concentration, such as respiratory gases moving between the pulmonary air sacs and the blood.
The _____________of diffusion depends on temperature, molecular weight, concentration differences, and the surface area and permeability of the membrane.
The net flow of water through a selectively permeable membrane.
Channel proteins that allow passage of water through plasma membranes.
The physical force that would be required to stop osmosis.
One mole of dissolved particles in a solution.
The number of osmoles of solute per liter of solution.
The ability of a solution to affect the fluid volume and pressure in a cell.
A solution is hypotonic, isotonic, or hypertonic to a cell if it contains a lower, equal, or greater concentration of nonpermeating solutes than that of its___________.
Employs membrane proteins to move solutes through a membrane and is usually specific for a particular solute.
Membrane carriers can become____________with solute molecules causing the inability to work any faster.
The maximum rate of transport.
A carrier that transports only one solute at a time.
A carrier that transports two or more solutes through the membrane in the same direction (cotransport).
A carrier that transports two or more solutes through the membrane in opposite directions (countertransport).
A form of carrier-mediated transport that moves solutes through a membrane down a concentration gradient, without an expenditure of ATP.
A form of carrier-mediated transport that moves solutes through a membrane up [against] a concentration gradient, with the expenditure of ATP.
An antiport that moves Na+ out of a cell and K+ into it.
The pump that serves for control of cell volume, secondary active transport, heat production, and maintenance of an electrical membrane potential.
The movement of substances in bulk through a membrane in membrane-enclosed vesicles.
Any form of vesicular transport that brings materials into a cell, including phagocytosis, pinocytosis, and receptor-mediated.
A form of vesicular transport that discharges material from a cell.
Composed of a clear gelatinous cytosol containing embedded organelles, the cytoskeleton, and inclusions.
internal structures in the cytoplasm that carry out specialized tasks for a cell.
___________________are enclosed in one or two layers of unit membrane similar to the plasma membrane.
The ribosomes, centrosome, centrioles, and basal bodies are ______________organelles.
The part of the cell that contains most of the cells DNA and is its genetic control center.
A network of cisternae that synthesizes phospholipids and steroids, detoxifies alcohol and other drugs, and produces a cells membranes.
A major site for protein synthesis within the cell.
A calcium storage reservoir in some cells.
Small protein-RNA granules found in the cytosol and on the rough ER and nuclear envelope. They synthesize proteins.
Part of the cell that synthesizes carbohydrates and processes many new proteins into their final form.
______________can become secretory vesicles bound for exocytosis or lysosomes retained in the cell.
Membrane-bounded packets of enzymes that degrade ingested matter, glycogen and other stored biochemicals and expired organelles. They also sometimes bring about programmed cell death.
Membrane-bounded packets of enzymes that oxidize various organic molecules.
Organelles specialized for ATP synthesis.
Short cylindrical arrays of microtubules. A pair functions in cell division, and a single one forms the basal bodies of cilia and flagella.
A supportive framework of protein filaments and tubules in a cell. It gives a cell its shape, organizes the cytoplasmic contents, and functions in movements of cell contents and the cell as a whole.
Part of a cell that is composed of microfilaments of the protein actin, intermediate filaments of keratin or other proteins, and cylindrical microtubules of the protein tubulin.
____________are either stored cellular products such as glycogen, pigments, and fat, or foreign bodies such as bacteria, viruses, and dust. They are not vital to cell survival.