1. Synaptic signaling
involves
A) endocrine signals
B) paracrine signals
C) autocrine signals
D) neurotransmitters
2. Characteristics of
intracellular receptors that regulate gene transcription include all of the
following except
A) a DNA binding site
B) an extracellular binding
site
C) a transcription
activating domain
D) may be signaled by lipid
soluble molecules
3. Cell surface receptors
may be any of the following except
A) G protein linked
B) enzymic receptors
C) single-pass transmembrane
proteins for neurotransmitters
D) chemically-gated ion
channels
4. In the cAMP pathway,
the G protein stimulates
A) phospholipase C
B) adenylyl cyclase
C) the endoplasmic reticulum
D) calmodulin
5. The ____ surrounds the
cell like a belt, preventing the passage of substances between the cells.
A) gap junction
B) desmosome
C) hemidesmosome
D) tight junction
6. In most cases protein
kinases
A) hydrolyze proteins
B) polymerize amino acids
C) stimulate adenylyl
cyclase
D) bind cGMP
E) add phosphate groups to
proteins
7. The receptor for nitric
oxide (NO) is
A) intercellular
B) intracellular
C) extracellular
D) ultracellular
E) unicellular
8. In desmosomes,
cadherins link to _______________ of an adjacent cell.
A) integrins
B) connexons
C) ras proteins
D) intermediate filaments
E) plasmodesmata
9. Which of the following
are NOT involved in enzyme activation?
A) A-kinase
B) P nucleic acid
C) cAMP
D) nitric oxide
E) G protein
10. ________ junctions may
protect a damaged cell through chemical gating.
A) Tight
B) Gap
C) Adherens
D) Occluding
E) Macular
11. Narrow gaps between
nerve cells through which paracrine signals travel are called
A) desmosomes
B) calmodulins
C) synapses
D) integrins
E) maculae
12. _______________ is a
common second messenger.
A) cAMP
B) cGTP
C) cMHC
D) cATP
E) cRNA
13. Paracrine signals
A) are long-lived with
widespread effects
B) are short-lived, but with
widespread effects due to cascades
C) are long-lived, but are
acting locally
D) are short-lived with
local effects
E) such as
neurotransmitters, function only intracellularly
14. In anchoring
junctions, cadherins are linked to
A) actin filaments in the
cell's cytoskeleton
B) cell walls of adjacent
cells in plants
C) connexons of its own and
adjacent cells
D) extracellular matrices of
adjacent cells
E) intracellular integrins
of most cells
15. Intracellular
receptors include those for
A) progesterone
B) vitamin D
C) cortisol
D) thyroid hormone
E) all of the above
16. Adherens junctions may
involve
A) extracellular matrix
B) integrins
C) actin filaments
D) all of the above
E) none of the above
17. With respect to the
plasma membrane, most enzymic receptors are
A) entirely internal
B) seven pass
C) entirely on the surface
D) multipass
E) single pass
18.A single-pass protein
that acts as a "self" marker is
A) GTP
B) MHC
C) GMP
D) MCA
E) ADP
19. Binding of epinephrin
to a G protein-linked receptor causes adenylyl cyclase to produce large amounts
of
A) A-kinase
B) G protein
C) phospholipase C
D) inositol triphosphate
E) cAMP
20.Cell signals with
short-lived local effects are called _______________
A) paracrine
B) apocrine
C) merocrine
D) holocrine
E) none of the above
21.Desmosomes are
associated with ____________ junctions.
A) adherens
B) tight
C) anchoring
D) communicating
E) lymphomas
22.One protein kinase
cascade begins with the phosphorylation of the
A) tap protein
B) gat protein
C) sat protein
D) ras protein
E) sap protein
23.Plasmodesmata
A) encircle cells of a tight
junction like a belt
B) connect to intermediate
fibers of the cytoskeleton
C) connect the cytoplasm of
one plant cell to that of another
D) connect actin fibers of
one cell to the extracellular matrix of another
E) is the name given to
desmosomes of plant cells
24.The signalling
molecules that travel the farthest are
A) endocrine
B) paracrine
C) neurotransmitter
D) intracellular
25.When a signal molecule
arrives at a G protein-linked receptor, the G protein
A) becomes deactivated
B) binds to the signal
molecule
C) becomes activated
D) binds with a Ca++
E) binds with calmodulin
26.Cells interact through
the actions of chemical signals which either bind to receptors on the membrane
or
A) pass through the plasma
membrane
B) trigger responses from
inside the cell
C) bind to intracellular
receptors
D) activate receptors that
bind to DNA
E) all of the above
27.Cell junctions that
prevent small molecules from passing in between two cells are called
A) gap junctions
B) tight junctions
C) adhesions
D) plasmodesmata
E) all of the above
28.In some tissues subject
to mechanical stress, special junctions called _______________ connect the
cytoskeletons of adjacent cells.
A) cadherin junctions
B) tight junctions
C) stress junctions
D) anchoring junctions
E) gap junctions
29.Gap junctions are
formed by
A) the fusion of plasma
membranes to form a single membrane
B) the insertion of protein
complexes that form tunnels between cells
C) protein hooks that extend
into the membrane of adjacent cells
D) gaps in the cell wall of
plants
E) none of the above
30.Plasmodesmata occur in
A) bacterial cells
B) all eukaryotic cells
C) plant cells
D) animal cells
E) the nucleus of the cell
31.A _______________ is a
type of adhering junction between animal cells.
A) tight junction
B) plasmodesma
C) chemical synapse
D) gap junction
E) c and d, but not a and b
32.Protein kinases are
enzymes that stimulate the production of hormones.
A) True
B) False
33.Hormones are relatively
long lived signals that travel throughout the body. This type of signalling is
called
A) paracrine signalling
B) synaptic signalling
C) autocrine signalling
D) endocrine signalling
E) direct contact
34.All of the following
statements apply to G proteins except
A) G proteins transmit a
signal from the cell surface to the interior of the cell
B) all G proteins have a
similar structure
C) G proteins do not use
second messengers but transmit the signal directly into the nucleus
D) G proteins act to amplify
the signal creating a cascade response in the cell
E) G proteins underlie the
actions of many medications
35.Receptors that are
recognized by the immune system are
A) immunoglobulins
B) MHC proteins
C) T receptor
D) B receptor
E) all of the above
ANSWER
- 1. D 2. B 3. C 4. B 5. D 6. E 7. B 8. D 9. B 10. B
- 11. C 12. A 13. D 14.A 15. E 16.D 17. E 18.B 19.E 20.A
- 21. C 22. D 23. C 24.A 25. C 26.E 27. B 28.D 29.B 30. C
- 31. A 32. B 33. D 34. C 35. E
