Cell Transport Exam Deck Flashcards
(34 cards)
Proteins in a membrane are
a. integral if they are embedded in the membrane and protrude from both surfaces of the bilayer
b. peripheral if they are on the inside surface held in place by the cytoskeleton
c. integral if they protrude from only one surface of the the bilayer
d. all of the choices are correct
D
Active Transport
a. requires an input of ATP
b. occurs in osmosis and facilitated transport
c. is inovlved in diffusion
d. all the choices correct
A
the channel protein that acount for why water can cross a membrane more quickly than expected is
a. aquaporin
b. integrin
c. the sodium potassium pump
d. ATP Synthetase
A
In a phospolipid bilayer the
a. fatty acid tails are hydrophilic
b. fatty acid tails are ionized
c. proteins are located only between the two layers
d. phosphate groups are hydrophobic
e. phosphate heads are oriented toward the exterior of tthe cell or toward the cytoplasm
E
Which statement is true about teh plasma membrane?
a. The fluid nature of the membrane is regulated by the flip-flopping of the phospholipids from one side of the membrane to the otther.
b. proteins and phospholipids can move sideways within the plane of the membrane
c. the model can be likened to a sandwich where phospholipids are like the bread and proteins are like the filing
d. The proteins make up the matrix of the membrane
B
Which statement is NOT true about the proteins in the plasma membrane?
a. glycoproteins contain carbohydrate chains that are oriented toward the inner surface of the membrane.
b. some peripheral proteins are connected to the cytoskeletal filaments
c. proteins may be attached to the inner surface of the plasma membrane
d. the hydrophobic portion of a protein is embedded within the membrane
e. integral proteins are responsible for membrane function
A
Which phrase does NOT describe one of the functions of proteins of the plasma membrane?
a. acting as a receptor for substances external to the cell
b. forming a channel through the membrane
c. binding to a substance to carry it through the membrane
d. initiating the replication of the genetic material
e. increasing the rate of chemical reaction
D
Red blood cells come in many “blood types” including A, B, AB, O (lacking proteins A and b), Rh positive, Rh negative (lacking Rh +) and many others. If blood is transfused, the recipient detects any new or “foreign” proteins. These blood type proteins are:
a. on the outer surface of the red blood cell membrane
b. inside the red blood cell cytoplasm
c. evernly distributed throughout the cell contents and plasma
d. in the red cell nucleus
e. in the plasma secreted by the red cell
A
Whether a molecule can cross the plasma membrane depends upon:
a. the chemical properties of the molecule
b. the charge of the molecule
c. the size of the molecule
d. the shape of the molecule
e. all of the above
E
If a cell is place in a hypotonic solution, which will occur?
a. Water will move out of the cell into the surrounding solution
b. water will move into the cell from teh surrounding solution
c. . Salts will move out of the cell into the surrounding solution
b. Salts will move into the cell from teh surrounding solution
B
Which is the best definition of osmosis?
The movement of water across a semi-permeable membrane from an area of higher water concentration to an area of lower water concentration
Which type of molecule will require some amount of energy to cross the cell membrane?
Polar
Freshwater protozoans react to a/an ________ environment by removing water through _____________.
Hypotonic, a contractile vacuole
The major functions of the plasma membrane do NOT include:
Production of proteins used in constrution of cell wall.
The do include: recognition and communication between cells and tissues; regulation of molecules and ions that pass in/out of cells; seperating fluid environments inside/outside of cell; maintaining connections to other cells.
Some parasites and isease agents regularly change their identity before our immune system can build up substantial antibodies. How could cells change their chemical identity on a regular basis?
a. cells eliminate all surface proteins and present only a naked lipid bilayer.
b. a new phospholipid bilayer is generated to replace the old layer.
c. because the membrane is “set”, the cell must reproduce and then the cell with the old membrane must die.
d. different glycolipids and glycoporteins are produced internally and moved into the plasma membrane.
e. rapid evolution produces mutations
D
Plants show turgor pressure when
cells contain water vacuoles that are full of water
Whic is the definition of active transport?
Movement of a SUBSTANCE against its concentration through the release of energy from ATP
A 10% glucose solution is placed in the thistle tube. The thistle tube is placed in a beaker that contains a 5% glucose solution. The solution in the thistle tube is __________ to the solution in the beaker.
Hypertonic
A 10% glucose solution is place din the thistle tube. The thisle tube is placed in a beaker that contains 5% glucose soluton. Where is the highest concentration of water found?
In the 5% solution
A 10% glucose solution is place din the thistle tube. The thisle tube is placed in a beaker that contains 5% glucose soluton. There is a differentially permeable membrane across the borad end of the tuge, which is permeable to water but not to sugar glucose. A diffusion occurs:
a. the 10% solution will become more concentrated and the 5% less concentrated.
b. the 10% solution will become less concentrated and the 5% more concentrated.
c. both will become more concentrated
d. both will become less concentrated
B
If the amount of water leaving a cell and entering the cell is the same (no net movement of water), what type of environment is the cell found in?
Isotonic
Eukaryotic cells are substantially larger than bacterial cells and average over 20 times more volume on surface than bacterial cells. How can the eukaryotic cell membrane provide this higher rate of exchange in materials?
a. plasma membrane folds increase surface area
b. large molecules are engulfed by vesicle formation
c. carrier proteins speed the rate at which a solute crosses the plasma membrane in the direction of decreasing concentration
d. mitochonidria are concentrated near membranes to provide energy for active transport of molecules or ions.
e. All of the above
E.
All life forms currently have a basic cell membrane so we presume that the earliest forms of life had this “fence” isolating the inernal organization from the external chaos. It is likely that the primordial environment was acidic. In order for a cell t funciton in this type of environment, the cell membrane would have to include:
A proton (H+) pump
If a living plant were moved from a feshwater aquarium to a saltwater aquarium, what would happen?
The plant’s cells would lose water and plasmolysis would occur.
