Bio 1100 Section 01 Spring 2011 Quiz #6: Name____KEY_____________________
B_______ 1) Which of the following cell types is likely to contain tight junctions?
A. red blood cells that travel singly through the circulatory system
B. cells lining the stomach, which prevent nutrients from leaking out
C. muscle cells in which the intermediate filaments of the cytoskeleton are bound to each other
D. cells of water-transporting tissue in plant stems
A_______ 2) Sponges are among the most ancient groups of animals. They have only a few cell types and relatively
simple bodies. If the cells of adult sponges from differently pigmented species A, B, and C were dissociated and then
mixed together in a culture dish, what would happen?
A. Adult sponges will re-form into species A, B, and C.
B. Adult sponges with a mixture of different pigmented cells will re-form.
C. The cells will remain dissociated.
D. The dissociated sponge cells will produce antibodies against the foreign sponge cells.
C_______3) Which of the following statements is false?
A) When plant cells are growing, they release expansins, which are enzymes that can expand the primary cell wall.
B) The secondary cell wall often contains structural components, like lignin, that form a relatively
rigid and complex network within the cell wall.
C) A plant cell continues growing after the secondary cell wall forms but stops growing with the formation
of the tertiary cell wall.
D) Pectin is a component of the cell wall that attracts and holds water.
D_______4) Pemphigus vulgaris is an autoimmune disorder in humans in which antibodies are produced against the
cadherins of desmosomes. The blistering of the skin and mucous membranes characteristic of this disorder is
probably a result of _____.
A) a decrease in flexibility of the cell membrane B) an inadequate number of G-protein receptors
C) inadequate production of cytoskeletal proteins D) a loss in cell-cell adhesion
B_______5) Acetylcholine is a neurotransmitter that binds to receptors on skeletal muscle cells. The receptor-signal
complex brings about a series of events that result in contraction of skeletal muscle. Venom from black
widow spiders causes an explosive release of acetylcholine. What would that do to its victims?
A) The victim's muscles would be unable to contract.
B) The victim's muscles would be unable to relax.
C) The victim's cell receptors would no longer be able to bind regulatory hormones.
D) The victim's cell receptors would be able to bind regulatory hormones but at a rate greatly
exceeding normal rates.
C_______6) Protein kinase is an enzyme that _____.
A) functions as a second messenger molecule
B) serves as a receptor for various signal molecules
C) activates or inactivates other proteins by adding a phosphate group to them
D) activates or inactivates other proteins by removing a phosphate group from them
A_______7) A G-protein receptor with GTP bound to it _____.
A) is in its active state
B) signals a protein to maintain its shape and conformation
C) will use cGMP as a second messenger
D) is in its inactive state
B_______8) Plasmodesmata are cell-cell junctions that are found between _____.
A) individual cardiac cells in heart muscle tissue
B) adjacent plant cells
C) adjacent animal cells in the same tissue type
D) the plasma membrane of actively dividing prokaryotes
C_______9) Put the steps of the process of signal transduction in the order they occur:
1. A conformational change in the signal-receptor complex activates an enzyme.
2. Protein kinases are activated.
3. A signal molecule binds to a receptor.
4. Target proteins are phosphorylated.
5. Second messenger molecules are released.
A) 1, 2, 3, 4, 5 B) 3, 1, 2, 4, 5 C) 3, 1, 5, 2, 4 D) 1, 2, 5, 3, 4
A_______10) One characteristic of life and living systems is that they are able to adapt. Toward this end, cells interact
with other cells and their environment through the action of their _____.
A) plasma membrane and extracellular matrix B) microtubular tracks
C) hormones D) intracellular electrical currents
BONUS QUESTIONS: (5 points)
B___________________ During Wednesday’s lecture, I told you guys a story about the previous morning when my daughter
asked me if she could have a __________________.
A) puppy B) cell phone C) princess costume D) Scooby Doo DVD E) Ipod
