Body fluid compartment contains high levels of K+, large anions, and proteins?
Intracellular fluid only
Which body fluid compartment contains higher levels of Na+, Cl-, and HCO3-?
Both plasma and interstitial fluid
All of the following are types of mediated transport except one. Identify the exception
Facilitated diffusion
Primary active transport
Simple diffusion
Secondary active transport
Simple diffusion
Bulk flow is fluid flow as a result of a ___ gradient.
Pressure
Water is a polar molecule, yet it easily moves through the nonpolar portions of cell membranes. Which trasport process is responsible?
Simple diffusion
Permeability is a property of
Membranes
The term cellular (metabolic) energy indicates any biological process requiring
ATP
What are the two extracellular fluid compartments in the body?
Plasma and interstitial
Saturation occurs when
A group of carrier proteins is operating at its maximum rate
The means by which a cell trasports large molecules out of the cell is called
Exocytosis
Which of the following is a way for solutes in an aqueous solution to move from an area of high solute concentration to an area of low solute concentration?
Only facilitated diffusion
In an epithelium, the apical membrane is also known as the ___ membrane
Mucosal
Have lower concentrations of solutes than hyperosmotic solutions
Hyposmotic solutions
Which of the following statements about the resting membrane potential is true?
It results, in part, from the concentration gradients for Na+ and K+
Voltage-gated (voltage-dependant) channels and antiport carriers are both types of
Transporters
The resting membrane potential in a typical nerve cell is approximately
-70mV
Compared to the outside surface, the inside of a resting cell membrane is
Negatively charged
Caveolae and clathrin-coated pits are both used in
Endocytosis
As the charge on the membrane of a typical neuron approaches 0 from -70 mV, the cell is
Only depolarizing
The ion that plays a key role in initiating electrical signals in neurons is
Na+
Which of the following is NOT involved in creating the resting potential of a neuron?
Diffusion of potassium ions out of the cell
Diffusion of sodium ions into the cell
Resting membrane permeability for sodium ions greater than potassium ions
Resting memb
Resting membrane permeability for sodium ions greater than potassium ions
Passive transport refers to a process that requires
No cellular energy
Which of the following is NOT true of diffusion in the human body?
Smaller molecules take longer to diffuse than larger ones
Gated channels for sodium ions may include:
Mechanical gates, which respond to pressure
Chemical gates, which respond to ligands
Voltage gates, which respond to electrical signals
All
None
All of the answers are correct
When a neuron changes its ion permeability from the resting state,
Only a variety of gated ion channels may open or close and Na+ channels may open allowing Na+ to enter the cell
Transfer signals from the extracellular environment to the cytoplasm of the cell
Receptors
Form cell to cell connections
Structural proteins
Bind to molecules to facilitate entry to or exit from the cell
Transporters
Ligands bind to these proteins and are changed by the protein
Enzymes
The movement of molecules from an area of high concentration to an area of low concentration
Passive transport
The movement of molecules via proteins embedded in the cell membrane; requires ATP
Active transport
The movement of molecules against the concentration gradient
Active transport
Tends to create an equilibrium state
Passive transport
The movement of molecules from an area of high concentration to an area of low concentration
Both- simple and facilitated diffusion
The use of ATP to move molecules
Neith simple nor facilitated diffusion
A form of mediated transport
Facilitated diffusion
Conforms to the properties of specificity, competition, and saturation
Facilitated diffusion
Between adjacent cells
Paracellular tansport
From an organ's lumen to the extracellular fluid
Absorption
In one side of a cell and out the other
Transcellular transport
Movement from the extracellular fluid into the lumen of an organ
Secretion
Na+ enters the cell
Depolarization
K+ leaves the cell
More than one answer
Cl- enters the cell
Hyperpolarization
Membrane potential is 0 mV
Depolarization
This type of membrane protein extends all the way through the cell membrane into both the extra and intracellular fluid
Membrane spanning
The membrane proteins that catalyze reactions that take place on the external or internal surface of the cell are
Enzymes
The membrane proteins that bind to a ligand and cat in the bodys chemical signaling system are
Receptors
The membrane proteins that provide for support of the cell membrane and allow for cells to connect to each other are
Structural proteins
The membrane proteins that change shape and bind with specific molecules to transport them across the cell membrane are
Carrier proteins
Carrier proteins operating at their maximum rate are said to be
Saturated
The three types of gated channels are ___, ___, and ___
Chemical, voltage, and mechanical
Membrane protein pores that can be opened and closed are called __ channels
Gated
A pump that helps maintain an electrical gradient, such as the Na+ -K+ -ATPase is an ___ pump
Electrogenic
Channel proteins that allow water to pass are called
Aquaporins
Membrane protein pores that are essentially always open are called ___ or __ channels
Open, leak
A unique characteristic of glucose as a solute in biological systems?
100% of it is absorbed into the cell from the extracellular fluid
The two extracellular compartments in the body are __ and __
Plasma, interstitial fluid
The walls of the ___ separate the two extracellular fluid compartments
Circulatroy system
The ability of a carrier molecule to trasport onely one specific molecule or a group of closely related molecules is
Specificity
At rest, nerve cells have an unequal distribution of ions on either side of the cell membrane, producing the
Resting membrane potential
At rest, nerve cells have a voltage of __ mV
-70
A cell membrane that is selectively permeable
Can change which substances pass through by changing its lipid and protein content
Fick's law of diffusion states that the rate of diffusion across a membrane is
Proportional to concentration gradient, surface area, and membrane permeability
Would increase the rate of diffusion across a cell membrane
A decrease of membrane thickness
Pinocytosis and potocytosis are types of
Endocytosis
Sodium ions are more concentrated in the extracellular fluid than in the intracellular fluid. This is an example of
Chemical disequilibrium
Which property of diffusion best helps explain the necessity of the circulatory system in multicellular organisms?
Diffusion is rapid over short distances but much slower over long distances
Facilitated diffusion and active transport differ in that
ATP is necessary for active transport, but not for facilitated diffusion
Water will always move from ___ areas to ___ areas, if there are no impermeable barriers.
Hyposmotic, hyperosmotic
Substances that readily dissolve in water and do not readily dissolve in lipids are
Hydrophlic and lipophobic
Which can move across the phospholipid bilayer by simple diffusion?
ALL lipids, steroids, water
Cations will __ each other
repel
Anions will ___ each other
repel
The cell membrane acts as a good
Electrical insulator
Resting membrane potential of -70 mV to +30 mV
Depolarization
From -50 mV to resting membrane potential of -70 mV
Repolarization
From -90 mV to resting membrane potential of -70 mV
Repolarization
The concentration of calcium inside a cell is 0.3%. The concentration of calcium outside the cell is 0.1%. How could the cell transport even more calcium to the inside?
Active Transport
Which body fluid compartment contains high levels of K+, large anions, and proteins?
Intracellular fluid only
Which of the following is a unique characteristic of glucose as a solute in biological systems?
100% of it is absorbed into the cell from the extracellular fluid.
Which of the following statements about the Na+/K+ pump is FALSE?
Its activity requires the expenditure of metabolic (cellular) energy.
It transports Na+ and K+ in a 1:1 ratio.
It transports Na+ out of the cell and K+ into the cell.
It is present in neuro
It transports Na+ and K+ in a 1:1 ratio
What is a nonpenetrating (NP) solute?
A solute that will not cross the cell membrane.
Membrane receptors are involved in various types of cell signaling. Some membrane receptors function as _____ channels.
Chemically gated
Cell membranes are primarily made of _____ molecules.
Phospholipids