Question 1

The activation of a membrane integrin by the binding of its cytoplasmic portion to molecules in the cytoplasm and the resultant increase in its affinity for an extracellular ligand is called ________.

Accepted Answer

A)  inside-out signaling
B)  outside-in signaling
C)  right-side-out signaling
D)  simple signaling
E)  integrinationF) A) and D)
G) C) and E)

Question 2

The bonds that selectins form with their ligands become _______ when the interaction is __________.

Accepted Answer

A)  stronger,placed under mechanical stress
B)  weaker,placed under mechanical stress
C)  stronger,exposed to a higher temperature
D)  more elastic,exposed to a higher temperature
E)  more elastic,placed under mechanical stressF) B) and D)
G) B) and E)

Question 3

Epidermolysis bullosa,an inherited blistering disease,is caused by ________.

Accepted Answer

A)  production of antibodies against hemidesmosome plaque proteins
B)  production of autoantibodies
C)  production of antibodies against spot desmosome plaque proteins
D)  genetic alterations in any one of a number of hemidesmosomal proteins
E)  production of antibodies against connexinsF) A) and B)
G) A) and C)

Question 4

The degradation of the extracellular matrix,along with cell surface proteins,is accomplished mostly by a _____-containing enzyme family called _______.

Accepted Answer

A)  copper,matrix metalloproteinases
B)  copper,MMPs
C)  zinc,matrix metalloproteinases
D)  magnesium,matrix metalloproteinases
E)  manganese,MMPsF) B) and D)
G) B) and C)

Question 5

You are investigating the interactions of integrin  α\alphaα  and  β\betaβ  subunits and isolate the extracellular portion of an integrin as a soluble  α\alphaα / β\betaβ  heterodimer.The heterodimer lacks the associated transmembrane and cytoplasmic domains normally present as part of the molecule.You experimentally link the  α\alphaα and  β\betaβ  subunits at the bases of their legs so that the ligand-binding regions of the  α\alphaα and  β\betaβ subunits approach one another.Which of the following statements is true about the molecules formed?

Accepted Answer

A)  The molecules bind their ligand tightly.
B)  The molecules are unable to bind a ligand.
C)  The molecules are cleaved.
D)  The molecules denature their ligand.
E)  The molecules denature and degrade. F) A) and D)
G) B) and D)

Question 6

Pemphigus vulgaris __________.

Accepted Answer

A)  is characterized by a loss of epidermal cell-cell adhesion
B)  is an autoimmune disease
C)  is characterized by severe blistering of the skin
D)  is caused by the production of antibodies against one of the desmogleins
E)  All of these are correct.F) A) and D)
G) A) and C)

Question 7

The tightest attachment between a cell and its extracellular matrix is seen at the site where an epithelial cell is attached to the underlying basement membrane.The specialized adhesive structure found at such a site is called a(n) ________.

Accepted Answer

A)  tight junction
B)  spot desmosome
C)  plasmodesma
D)  hemidesmosome
E)  gap junctionF) A) and B)
G) A) and C)

Question 8

All collagen family members consist of _____ chains arranged in a _______.

Accepted Answer

A)  2,double helix
B)  3,double helix
C)  3,triple helix
D)  3,triple lattice
E)  2,triple helixF) A) and B)
G) D) and E)

Question 9

Which tissues below are not typically derived from the single-celled epithelium on the dorsal surface of a chick embryo after gastrulation?

Accepted Answer

A)  muscle
B)  skin,ectodermal tissues and nervous system
C)  skin
D)  ectodermal tissues
E)  nervous systemF) A) and C)
G) A) and D)

Question 10

While most IgSF members are involved in various aspects of immune function,some of them mediate ________ cell-cell adhesion.

Accepted Answer

A)  calcium-dependent
B)  calcium-independent
C)  magnesium-dependent
D)  manganese-dependent
E)  iron-independentF) A) and E)
G) A) and C)

Question 11

Which protein below is thought to be secreted into the extracellular matrix that surrounds the lining of mature blood vessels,where it inhibits angiogenesis?

Accepted Answer

A)  tenascin
B)  entactin
C)  thrombospondin
D)  actin
E)  lamininF) A) and E)
G) A) and B)

Question 12

What proteins have been shown to be altered by genetic mutations in patients who suffer from epidermolysis bullosa?

Accepted Answer

A)  the  α\alphaα 6 integrin subunit
B)  the  β\betaβ 4 integrin subunit
C)  collagen VII
D)  laminin-5
E)  All of these are correct. F) A) and D)
G) A) and E)

Question 13

What is thought to be the origin of immunoglobulins?

Accepted Answer

A)  They may be derived from immune system molecules in invertebrates.
B)  They may be derived from cell-adhesion receptors in invertebrates.
C)  They may be derived from cell-adhesion receptors in fish.
D)  They may be derived from cell-adhesion molecules in amphibians.
E)  They may be derived from immune system molecules in reptiles.F) C) and E)
G) C) and D)

Question 14

In the intercellular junctional complex,why is the tight junction closer to the surface of the epithelium (the apical end of the cell)than the belt desmosome?

Accepted Answer

As an example,consider the intestinal ep...

Question 15

Why do cells flatten out as they make contact with a surface?

Accepted Answer

A)  They lose water.
B)  They extrude cytoplasm.
C)  They send out projections that make increasingly stable attachments.
D)  Their membranes stiffen.
E)  They make focal assignations.F) A) and B)
G) A) and C)

Question 16

When tight junctions,gap junctions and desmosomes are arranged in a specific array,the assortment of surface specializations is called a(n) __________.

Accepted Answer

A)  junctional array
B)  synaptonemal complex
C)  belt complex
D)  junctional complex
E)  spot complexF) A) and B)
G) A) and E)

Question 17

Evidence strongly suggests that the bent conformation of an integrin is _______ and unable to bind its ligand.

Accepted Answer

A)  loose
B)  active
C)  tight
D)  stretched
E)  inactiveF) B) and C)
G) A) and B)

Question 18

What determines the strength of adhesion between apposing cells held together by cadherins?

Accepted Answer

A)  the length of the cadherins connecting the cells
B)  the width of the cadherins connecting the cells
C)  the amount of tryptophan in the cadherins connecting the cells
D)  the number of cadherins in a cluster connecting the cells
E)  the number of tyrosine residues in the cadherins connecting the cellsF) A) and B)
G) D) and E)

Question 19

What would be the effect on primordial germ cells when an embryo is exposed to laminin-specific antibodies?

Accepted Answer

A)  They arrive at the developing gonad more quickly.
B)  Their movement to the developing gonad is disrupted.
C)  They begin to divide rapidly.
D)  They increase greatly in size.
E)  Their nuclei disintegrate.F) D) and E)
G) A) and D)

Question 20

Lymphocytes are isolated and labeled with radioactive isotopes.They are then exposed to frozen tissue sections of a lymphoid organ.What happens?

Accepted Answer

A)  The lymphocytes bind uniformly to the sections.
B)  The lymphocytes bind to each other.
C)  The lymphocytes selectively adhere to the endothelial lining of venules in peripheral lymph nodes.
D)  The lymphocytes selectively adhere to the endothelial lining of arterioles in peripheral lymph nodes.
E)  The lymphocytes do not stick to the sections.F) A) and D)
G) A) and C)

Exam 7: Interactions Between Cells and Their Environment

The degradation of the extracellular matrix,along with cell surface proteins,is accomplished mostly by a _-containing enzyme family called ___.

Correct Answer
verified

Pemphigus vulgaris __________.

Correct Answer
verified

Epidermolysis bullosa,an inherited blistering disease,is caused by ________.

Correct Answer
verified

While most IgSF members are involved in various aspects of immune function,some of them mediate ________ cell-cell adhesion.

Correct Answer
verified

Which tissues below are not typically derived from the single-celled epithelium on the dorsal surface of a chick embryo after gastrulation?

Correct Answer
verified

Correct Answer
verified

What would be the effect on primordial germ cells when an embryo is exposed to laminin-specific antibodies?

Correct Answer
verified

In the intercellular junctional complex,why is the tight junction closer to the surface of the epithelium (the apical end of the cell)than the belt desmosome?

Correct Answer
verified
As an example,consider the intestinal ep...
View Answer

The tightest attachment between a cell and its extracellular matrix is seen at the site where an epithelial cell is attached to the underlying basement membrane.The specialized adhesive structure found at such a site is called a(n) ________.

Correct Answer
verified

What proteins have been shown to be altered by genetic mutations in patients who suffer from epidermolysis bullosa?

Correct Answer
verified

Why do cells flatten out as they make contact with a surface?

Correct Answer
verified

When tight junctions,gap junctions and desmosomes are arranged in a specific array,the assortment of surface specializations is called a(n) __________.

Correct Answer
verified

What is thought to be the origin of immunoglobulins?

Correct Answer
verified

What determines the strength of adhesion between apposing cells held together by cadherins?

Correct Answer
verified

Lymphocytes are isolated and labeled with radioactive isotopes.They are then exposed to frozen tissue sections of a lymphoid organ.What happens?

Correct Answer
verified

All collagen family members consist of _ chains arranged in a ___.

Correct Answer
verified

Evidence strongly suggests that the bent conformation of an integrin is _______ and unable to bind its ligand.

Correct Answer
verified

The bonds that selectins form with their ligands become _ when the interaction is ____.

Correct Answer
verified

The activation of a membrane integrin by the binding of its cytoplasmic portion to molecules in the cytoplasm and the resultant increase in its affinity for an extracellular ligand is called ________.

Correct Answer
verified

Which protein below is thought to be secreted into the extracellular matrix that surrounds the lining of mature blood vessels,where it inhibits angiogenesis?

Correct Answer
verified

Exam 7: Interactions Between Cells and Their Environment

The degradation of the extracellular matrix,along with cell surface proteins,is accomplished mostly by a _____-containing enzyme family called _______.

Correct AnswerverifiedShow Answer

Pemphigus vulgaris __________.

Correct AnswerverifiedShow Answer

Epidermolysis bullosa,an inherited blistering disease,is caused by ________.

Correct AnswerverifiedShow Answer

While most IgSF members are involved in various aspects of immune function,some of them mediate ________ cell-cell adhesion.

Correct AnswerverifiedShow Answer

Which tissues below are not typically derived from the single-celled epithelium on the dorsal surface of a chick embryo after gastrulation?

Correct AnswerverifiedShow Answer

Correct AnswerverifiedShow Answer

What would be the effect on primordial germ cells when an embryo is exposed to laminin-specific antibodies?

Correct AnswerverifiedShow Answer

In the intercellular junctional complex,why is the tight junction closer to the surface of the epithelium (the apical end of the cell)than the belt desmosome?

Correct AnswerverifiedAs an example,consider the intestinal ep...View AnswerShow Answer

The tightest attachment between a cell and its extracellular matrix is seen at the site where an epithelial cell is attached to the underlying basement membrane.The specialized adhesive structure found at such a site is called a(n) ________.

Correct AnswerverifiedShow Answer

What proteins have been shown to be altered by genetic mutations in patients who suffer from epidermolysis bullosa?

Correct AnswerverifiedShow Answer

Why do cells flatten out as they make contact with a surface?

Correct AnswerverifiedShow Answer

When tight junctions,gap junctions and desmosomes are arranged in a specific array,the assortment of surface specializations is called a(n) __________.

Correct AnswerverifiedShow Answer

What is thought to be the origin of immunoglobulins?

Correct AnswerverifiedShow Answer

What determines the strength of adhesion between apposing cells held together by cadherins?

Correct AnswerverifiedShow Answer

Lymphocytes are isolated and labeled with radioactive isotopes.They are then exposed to frozen tissue sections of a lymphoid organ.What happens?

Correct AnswerverifiedShow Answer

All collagen family members consist of _____ chains arranged in a _______.

Correct AnswerverifiedShow Answer

Evidence strongly suggests that the bent conformation of an integrin is _______ and unable to bind its ligand.

Correct AnswerverifiedShow Answer

The bonds that selectins form with their ligands become _______ when the interaction is __________.

Correct AnswerverifiedShow Answer

The activation of a membrane integrin by the binding of its cytoplasmic portion to molecules in the cytoplasm and the resultant increase in its affinity for an extracellular ligand is called ________.

Correct AnswerverifiedShow Answer

Which protein below is thought to be secreted into the extracellular matrix that surrounds the lining of mature blood vessels,where it inhibits angiogenesis?

Correct AnswerverifiedShow Answer

The degradation of the extracellular matrix,along with cell surface proteins,is accomplished mostly by a _-containing enzyme family called ___.

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified
As an example,consider the intestinal ep...
View Answer

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

All collagen family members consist of _ chains arranged in a ___.

Correct Answer
verified

Correct Answer
verified

The bonds that selectins form with their ligands become _ when the interaction is ____.

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified