cô mai

1/ Rank the following terms from simplest to most complex (Arrange the following terms from simplest structure to most complex structure.: cells, organelles, organs, tissue, organism.

Organelles → Cells → Tissue → Organs → Organism. 

2/ Produce energy to fuel the cell’s activities

a. cytoplasm    b. centrioles c. mitochonria          d. Golgi bodies/golgi apparatus

mitochonria

3/ Holds the genetic infromation (DNA) for the cell. It controls all cell activites

a. cytoplasm            b. cell membrane                c. nucleus     d. Golgi bodies

nucleus

4/ Acts as the digestive system inside a cell. It helps to break down old or unneeded parts of the cell, and substances that have been brought into the cell from the outside.

a. lysosome  b. ribosome     c. endoplasmic reticulum    d. mitochondria

lysosome

5/ Monitors and controls entry into and out of the cell.

a. vacuole                b. ribosome             c. cell membrane                  c. nucleus

cell membrane   

6/ Creates proteins. It can float within the cytoplasm or be attached to an organelle.

a. mitochondria                   b. ribosome              c. cytoplasm            c. nucleus

ribosome

7/ Checks, makes necessary changes, packages and secretes proteins

a. endoplasmic reticulum    b. centrioles c. mitochonria  d. golgi apparatus

golgi apparatus

8/ Helps transport proteins

a. endoplasmic reticulum    b. ribosome             c. centrioles             c. nucleus

endoplasmic reticulum 

9/ What parts of the cell provide energy?

a.       centrioles                 b. lysosomes            c. mitochondria                    d. chromatin

mitochondria

10/ Which cell feature is responsible for making proteins?

1. Lysosomes  b. Ribosomes            c. Mitochondria       d. Golgi apparatus

Ribosomes

11/ Which of the following is the energy supplier for the cell; this organelle contains its own DNA

a. Lysosome        b. Mitochondria                  c.  Golgi apparatus  d.

Mitochondria

12/ The cell membrane is composed of ………………

a.   A single layer of proteins          b. A phospholipid bi-layer

c. A carbohydrate bi-layer                     d. A single layer of lipids

A phospholipid bi-layer

13/ The ………………..acts as a packaging and processing center in the cell to process proteins.

a.   Smooth E.R.     b. Rough E.R.        c. Golgi body          d.  Nucleus

Golgi body

14/ The outer most boundary of an animal cell is ……………………

a.   The cell wall                                   b. the cytoskeleton

c. Nuclear envelope                        d. the cell membrane

the cell membrane

15/ Cell contents are isolated from many substances in the environment due to the high concentration of……………..in the cell membrane

a.   Phospholipids and cholesterol         b. Proteins   c. Nucleic acids       d. Enzymes

Phospholipids and cholesterol        

16/ A cell that had relatively few energy needs would probably have a relatively small number of

a.   Chromosomes         b. lysosomes   c. ribosomes       d. mitochondria

mitochondria

17/ Eukaryotic cells are substantially larger than bacterial cells and average over 20 times more volume-per-surface-area than bacterial cells. How can the eukaryotic cell membrane provide this higher rate of exchange of materials?

a. Plasma membrane folds increase the surface area.
b. Carrier proteins speed the rate at which a solute crosses the plasma membrane in the direction of decreasing concentration.
c. Mitochondria are concentrated near membranes to provide energy for active transport of molecules or ions.
d. Large molecules are engulfed by vesicle formation.
e. All of the choices are correct.

All of the choices are correct.

18/ When red blood cells are placed in a concentrated salt solution, they will…………….

a.   Enlarge, but not burst                           b. Enlarge until they burst

c. Remain unchanged                                 d. shrink

shrink

19/ Which of the following processes requires both carrier molecules and energy?

a.   Osmosis                               b. facilitated transport

c. active transport                       d. all a, b and c require carriers and energy

active transport 

+ Which of the following substances is able to freely move across the cell membrane?

a.   Glucose                                           b. lipid soluble molecules

c. water soluble proteins           d. Na+

lipid soluble molecules

+ When two solutions that differ in solute concentration are placed on either side of a semi-permeable membrane and osmosis is allowed to occur, which of the following will happen?

a. Water will move from an area of high solute concentration to an area of low solute concentration

b. There will be no net movement of water

c. The solute will move from the area of high concentration to an area of low concentration

d. Water will move from an area of low solute concentration to an area of high solute concentration

Water will move from an area of low solute concentration to an area of high solute concentration

+ The concentration of calcium in a cell is 0.3%. The concentration of calcium in the fluids surrounding the cell is 0.1%. How could the cell obtain more calcium?

a. facilitated diffusion                                             b. active transport

c. diffusion                                                              d. osmosis

active transport

+ Which statement is correct concerning the sodium-potassium pump?

a. an equal concentration of sodium and potassium ions are exchanged

b. it is used in order to generate ATP for cellular activities

c. the ions move directly through the phospholipids of the plasma membrane

d. sodium ions are pumped out of the cell

sodium ions are pumped out of the cell

+ Which of the following pieces of evidence would suggest that a substance entered a cell via active transport as opposed to passive transport?

a.   ATP was required for transport

b.  the substance moved across the membrane via a carrier protein

c.   the substance moved from a high concentration to a low concentration

d.  none of the above

ATP was required for transport

+ Which one of the following cell structures exhibits selective permeability between a cell and its external environment?

a. the plasma membrane                             b.  mitochondria
c.  chloroplasts                                            d. endoplasmic reticulum
e.  lysosomes

the plasma membrane

+ Which of the following statements about the role of phospholipids in forming membranes is correct? 

a. Phospholipids are completely insoluble in water.
b. Phospholipids form a single sheet in water.
c. Phospholipids form a structure in which the hydrophobic portion faces outward.
d. Phospholipids form a selectively permeable structure.
e. They are triacylglycerols, which are commonly available in foods.

Phospholipids form a selectively permeable structure.

+ The plasma membrane is referred to as a "fluid mosaic" structure. Which of the following statements about that model is true?

a. The fluid component of the membrane is composed of phospholipids, and the mosaic part is composed of carbohydrates.
b. The fluid aspect of the membrane describes its structure at normal temperatures, and the mosaic aspect describes the membrane as the temperature is lowered.
c. The mosaic comprises the carbohydrate chains on the inner surface of the membrane.
d. The fluid component of the membrane is phospholipid, and the mosaic is protein.
e. Only phospholipids are capable of moving in the membrane.

The fluid component of the membrane is phospholipid, and the mosaic is protein.

+ Which of the following functional processes result(s) from the presence of proteins in or on the plasma membrane? a. enzymatic activity b. cell-cell recognition c.intercellular joining d. cell-cell communication e. all of the above

all of the above

+ Consider the currently accepted fluid mosaic model of the plasma membrane. Where in the plasma membrane would cholesterol most likely be found?

a. on the outside (external) surface of the membrane
b. in the interior of the membrane.

c.  on the inside (cytoplasmic) surface
d. in the interior and on the inside surface, but not on the outside surface
e. on either surface of the membrane, but not in the interior of the membrane

in the interior of the membrane.

+ Which of the following is/are a function of membrane proteins?

a. Membrane proteins attach the membrane to the cytoskeleton.
b. Membrane proteins provide receptors for chemical messengers.
c. Membrane proteins form channels, which move substances across the membrane.
d. Membrane proteins with short sugar chains form identification tags that are recognized by other cells.
e. all of the above

All of the above

+ Which one of the following statements concerning carbohydrates associated with the plasma membrane is correct?

a. Carbohydrates are only found associated with the membranes of prokaryotic cells.
b. The carbohydrate composition of most eukaryotic plasma membranes is quite similar.
c. Carbohydrates on the plasma membrane are typically short chains of 2-5 monosaccharides.
d. Membrane carbohydrates function primarily in cell-cell recognition.
e. Carbohydrates associated with the plasma membrane are located on both surfaces of the membrane.

Carbohydrates on the plasma membrane are typically short chains of 2-5 monosaccharides.

+ Which statement(s) about the sidedness of the plasma membrane is (are) correct? 

a. Parts of proteins that are exposed on the cytoplasmic side of the endoplasmic reticulum are also exposed on the cytoplasmic side of the plasma membrane.
b. The asymmetrical distribution of membrane proteins, lipids, and carbohydrates across the plasma membrane is determined as the membrane is being constructed.
c. Every integral membrane protein has a specific orientation in the plasma membrane.
d. The two lipid layers may differ in specific lipid composition.
e. all of the above

all of the above

+ Which one of the following molecules is most likely to diffuse freely across the lipid bilayer of the plasma membrane without the involvement of a transport protein? a.carbon dioxide b.glucose c.sodium ion d.DNA e.hemoglobin

Carbon dioxide (CO₂)

+ Which of the following would be least likely to diffuse through a plasma membrane without the help of a transport protein?

a. a large polar molecule
b. a large nonpolar molecule
c. dissolved gases such as oxygen or carbon dioxide
d. a small nonpolar molecule
e. Any of the above would easily diffuse through the membrane.

A large polar molecule

+ Which of the following structures is most consistent with the selective permeability property of biological membranes?

a.proteins sandwiched between two layers of phospholipid
b.proteins embedded in two layers of phospholipid
c. a layer of protein coating a layer of phospholipid
d.phospholipids sandwiched between two layers of protein
e.a phospholipid bilayer with proteins scattered on the surfaces of the membranes

Proteins embedded in two layers of phospholipid

+ Which of the following statements about passive transport is correct? a. Passive transport operates independently of diffusion. b. Passive transport operates independently of the concentrations of the substance being transported. c. In passive transport, all movement of the transported molecule stops when its concentration is the same on both sides of the membrane. d. Passive transport does not occur in the animal body. e. Passive transport permits the transported molecule to move in either direction, but the majority of transport occurs down the concentration gradient of the molecule.

Passive transport permits the transported molecule to move in either direction, but the majority of transport occurs down the concentration gradient of the molecule

+ Diffusion and osmosis are both forms of

a.       active transport.                  b. passive transport.            c. respiration.          

d. photosynthesis.         e. glycolysis.

Passive transport

+ The                 controls the movement of materials into and out of the cell.

a. cell membrane     b. nucleus                c. cytoplasm            d. mitochondrion

cell membrane    

+ The movement of water from an area of higher concentration to an area of lower concentration is known as:

         a. diffusion  b. osmosis    c. Active transport  d. Hydrolysis   e. Phagocytosis

osmosis

+ Eukaryotic cells are substantially larger than bacterial cells and average over 20 times more volume-per-surface-area than bacterial cells. How can the eukaryotic cell membrane provide this higher rate of exchange of materials?

a. Plasma membrane folds increase the surface area.
b. Carrier proteins speed the rate at which a solute crosses the plasma membrane in the direction of decreasing concentration.c. Mitochondria are concentrated near membranes to provide energy for active transport of molecules or ions.
d. Large molecules are engulfed by vesicle formation.
e. All of the choices are correct.

All of the choices are correct.

+  Cells A and B are the same size, shape, and temperature, but cell A is metabolically quiet and cell B is actively consuming oxygen. Oxygen will diffuse more quickly into cell _____ because _____. 

a. A; the diffusion gradient there is shallower
b. A; its membrane transport proteins will not be saturated
c. B; the diffusion gradient in cell B is steeper
d. B; the oxygen molecules inside cell B have a higher kinetic energy
e. B; the gradient of oxygen is oriented in the opposite direction compared to cell A

c. B; the diffusion gradient in cell B is steeper

+ Which one of the following statements about diffusion is true?

a. It is very rapid over long distances.
b. It requires expenditure of energy by the cell.
c. It is a passive process.
d. It occurs when molecules move from a region of lower concentration to a region of higher concentration.
e. It always requires integral proteins of the cell membrane

c. It is a passive process.

+ Which of these statements describes some aspect of facilitated diffusion?

a. Facilitated diffusion is another name for osmosis.
b. Facilitated diffusion of solutes occurs through phospholipid pores in the membrane.
c. Facilitated diffusion requires energy to drive a concentration gradient.
d. Facilitated diffusion of solutes may occur through protein pores in the membrane.
e. There is only one kind of protein pore for facilitated diffusion.

d. Facilitated diffusion of solutes may occur through protein pores in the membrane.

+ Which of the following is true about facilitated diffusion?

a. Facilitated diffusion requires a concentration gradient.
b. Facilitated diffusion requires a membrane.
c. Facilitated diffusion involves proteins.
d. Facilitated diffusion does not involve an outside energy source.
e. all of the above

e. all of the above

+ Active transport requires a cell to expend energy. Which of the following statements is true?

a. Active transport often involves an ATP-powered ion pump and a cotransport protein.
b. Active transport usually uses ATP as its energy source.
c. Active transport moves solutes against the concentration gradient.
d. Active transport requires a protein carrier.
e. all of the above

e. all of the above

+ Which of the following is a correct difference between active transport and facilitated diffusion?

a. Active transport involves transport proteins, and facilitated diffusion does not.
b. Facilitated diffusion can move solutes against a concentration gradient, and active transport cannot.
c. Active transport can move solutes in either direction across a membrane, but facilitated diffusion can only move in one direction.
d. Facilitated diffusion involves transport proteins, and active transport does not.
e. Active transport requires energy from ATP, and facilitated diffusion does not.

e. Active transport requires energy from ATP, and facilitated diffusion does not.

+ Which of the following enables a cell to pick up and concentrate a specific kind of molecule?

a. passive transport b. facilitated diffusion        c. osmosis               
d.  receptor-mediated endocytosis              e. channel proteins

d.  receptor-mediated endocytosis   

+ Which of the following processes, normally associated with membrane transport, must occur to account for an increase in the surface area of a cell?

a. endocytosis
b. active transport
c. receptor-mediated endocytosis
d. exocytosis
e. flip-flop of phospholipids from one side of the plasma membrane to the other

d. exocytosis

+ The transmission of nerve impulses between adjacent nerve cells requires the release of a neurotransmitter (a molecule or small peptide by exocytosis). Which of the following would best reverse the process that resulted in the release of neurotransmitter, returning the cell to its original state?

a. endocytosis         b. pinocytosis
c. active transport of the neurotransmitter back into the cell
d. passive transport (by facilitated diffusion. of the neurotransmitter back into the cell
e. receptor-mediated endocytosis

a. endocytosis    

+ Which one of the following pairs correctly matches a membrane transport process to its primary function?

a. phagocytosis; secretion of large particles from the cell by fusion of vesicles with the plasma membrane
b. exocytosis; the movement of water and solutes out of the cell by vesicle fusion with the plasma membrane
c. pinocytosis; the uptake of water and small solutes into the cell by formation of vesicles at the plasma membrane.
d. osmosis; passive diffusion of water and small solutes across a membrane
e. none of the above

c. pinocytosis; the uptake of water and small solutes into the cell by formation of vesicles at the plasma membrane.

+ In what way do the membranes of a eukaryotic cell vary?

a. Phospholipids are found only in certain membranes.
b. Certain proteins are unique to each membrane.
c. Only certain membranes of the cell are selectively permeable.
d. Only certain membranes are constructed from amphipathic molecules.
e. Some membranes have hydrophobic surfaces exposed to the cytoplasm, while others have hydrophilic surfaces facing the cytoplasm.

b. Certain proteins are unique to each membrane.

+ According to the fluid mosaic model of membrane structure, proteins of the membrane are mostly

a. spread in a continuous layer over the inner and outer surfaces of the membrane.
b. confined to the hydrophobic core of the membrane.
c. embedded in a lipid bilayer.
d. randomly oriented in the membrane, with no fixed inside-outside polarity.
e. free to depart from the fluid membrane and dissolve in the surrounding solution.

c. embedded in a lipid bilayer.

+ Which of the following factors would tend to increase membrane fluidity?

a. a greater proportion of unsaturated phospholipids
b. a greater proportion of saturated phospholipids
c.  a lower temperature
d. a relatively high protein content in the membrane
e.  a greater proportion of relatively large glycolipids compared with lipids having smaller molecular masses

a. a greater proportion of unsaturated phospholipids

+. A major chemical that regulates the fluidity of animal cell membranes by stiffening the membrane at higher temperatures and preventing the membrane from freezing at lower temperature is:

a. cholesterol           b. lipid in nature.                 c. a steroid.
d. All of the choices are correct.

d. All of the choices are correct.

+ Proteins in a membrane are:

a. peripheral if they are on the inside surface held in place by the cytoskeleton.
b. integral if they are embedded in the membrane and protrude from both surfaces of the bilayer.
c. integral if they protrude from only one surface of the bilayer.
d. All of the choices are correct.

d. All of the choices are correct.

+ Active transport

a. requires an input of ATP.                                b. is involved in diffusion.
c. occurs in osmosis and facilitated transport.        d. All of the choices are correct.

a. requires an input of ATP.           

+ In a phospholipid bilayer, the

a. phosphate groups are hydrophobic.             b. fatty acid tails are ionized.
c. fatty acid tails are hydrophilic.       

d. proteins are located only between the two layers.
e. phosphate heads are oriented toward the exterior of the cell or toward the cytoplasm.

e. phosphate heads are oriented toward the exterior of the cell or toward the cytoplasm.

+ Which statement is true about the plasma membrane?

a. The proteins make up the matrix of the membrane.
b. The model can be likened to a sandwich where phospholipids are like the bread and proteins are like the filling.
c. The fluid nature of the membrane is regulated by flip-flopping of the phospholipids from one side of the membrane to the other.

d. The movement of proteins and phospholipids can occur sideways within the plane of the membrane.

d. The movement of proteins and phospholipids can occur sideways within the plane of the membrane.

+ Which statement is NOT true about the proteins in the plasma membrane?

a. Proteins may be attached to the inner surface of the plasma membrane.
b. The hydrophobic portion of a protein is embedded within the membrane.
c. Some peripheral proteins are connected to cytoskeletal filaments.
d. Integral proteins are responsible for membrane functions.
e. Glycoproteins contain carbohydrate chains that are oriented toward the inner surface of the membrane.

e. Glycoproteins contain carbohydrate chains that are oriented toward the inner surface of the membrane.

+ Which phrase does NOT describe one of the functions of proteins of the plasma membrane?

a. forming a channel through the membrane
b. initiating the replication of the genetic material
c. binding to a substance to carry it through the membrane
d. acting as a receptor for substances external to the cell
e. increasing the rate of a chemical reaction

b. initiating the replication of the genetic material