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Questions and Answers

What is the result of a severe desmoglein 3 deficiency?

Formation of desmosomes

Formation of hemidesmosomes

Blistering of the skin with leakage of body fluids (correct)

Increased cell-cell adhesion

Which type of intermediate filaments is found in epithelial cells?

Desmin filaments

Laminin filaments

Keratin filaments (correct)

Actin filaments

What is the function of anchoring junctions?

To regulate cell division

To regulate cell signaling pathways

To attach cells to each other or to the matrix (correct)

To provide mechanical support to cells

Which type of junctions is involved in cell-cell adhesion?

Desmosomes Signup and view all the answers

What is the function of hemidesmosomes?

To attach cells to the matrix Signup and view all the answers

Which protein is involved in the attachment of intermediate filaments to hemidesmosomes?

Plectin Signup and view all the answers

What is the consequence of autoantibodies attacking type XVII collagen in bullous pemphigoid?

Blistering of the skin Signup and view all the answers

What is the consequence of mutations in plectin?

Skin blisters associated with late-onset muscular dystrophy Signup and view all the answers

What is the function of desmoglein and desmocollin?

To bind to anchor proteins and intermediate filaments Signup and view all the answers

What is the result of desmosome disruption in skin autoimmune diseases like Pemphigus?

The skin epithelial cells are separated Signup and view all the answers

What type of proteins are desmoglein and desmocollin?

Cadherin proteins Signup and view all the answers

Where are desmosomes most abundant?

Tissues exposed to mechanical stress Signup and view all the answers

What is the role of desmoplakin, plakoglobin, and plakophilin?

To link cadherin proteins to intermediate filaments Signup and view all the answers

What is the purpose of desmosomes?

To hold cells together Signup and view all the answers

What is the result of desmoglein and desmocollin binding to anchor proteins?

The binding of cells to intermediate filaments Signup and view all the answers

Where are desmosomes found?

In many tissues, especially in skin and heart muscle Signup and view all the answers

What is the main function of anchoring junctions?

To anchor cells to the extracellular matrix or to other cells Signup and view all the answers

What is the role of integrins in focal adhesions?

To bind to laminin protein in the basal lamina Signup and view all the answers

What is the consequence of mutations in plectin?

Skin blisters Signup and view all the answers

What is the function of hemidesmosomes?

To facilitate the adhesion of cells to the basal lamina Signup and view all the answers

What is the role of the cytoplasmic domain of integrins in focal adhesions?

To bind to actin filaments Signup and view all the answers

What type of collagen is attacked by autoantibodies in bullous pemphigoid?

Type XVII collagen Signup and view all the answers

What is the main function of desmoglein and desmocollin?

To facilitate cell-cell adhesion Signup and view all the answers

What is the characteristic of hemidesmosomes?

They have a single dense plaque on the cytoplasmic surface Signup and view all the answers

What is the primary function of microvilli?

To increase the surface area of the cell for absorption Signup and view all the answers

What are the proteins that cross-link actin filaments in microvilli?

Fimbrin and villin Signup and view all the answers

What is the characteristic of glycocalix around microvilli?

It is thicker Signup and view all the answers

What is the function of cilia in epithelial cells?

To move the fluid over the surface of the cell Signup and view all the answers

Where are cilia typically found in the human body?

In the upper respiratory tract and uterine tubes Signup and view all the answers

What is the structure of cilia composed of?

Microtubules Signup and view all the answers

What is the composition of a triplet microtubule in a basal body?

One complete microtubule and two incomplete microtubules Signup and view all the answers

What is the structure that extends from the basal body into the apical cytoplasm?

Rootlet Signup and view all the answers

What is the function of basal bodies in the organization of cilia and flagella?

They organize the axoneme microtubules Signup and view all the answers

What is the difference between a basal body and a centriole?

Basal bodies have accessory structures such as basal foot and rootlet Signup and view all the answers

What is the significance of ciliary movement during development?

It is involved in the organization of internal organs Signup and view all the answers

What is the characteristic of cilia in patients with Kartagener's Syndrome?

They are immobile Signup and view all the answers

What is the role of nodal cilia in development?

They help in the organization of internal organs Signup and view all the answers

What is the main function of the flagellum in mammalian sperm?

To propel the sperm during fertilization Signup and view all the answers

What is the characteristic of microtubules?

They are hollow tube-like structures composed of 13 protofilaments Signup and view all the answers

What is the significance of the helical beating of cilia at the node?

It is responsible for the origin of left-right asymmetry Signup and view all the answers

What is the main difference between flagella and cilia?

The type of movement they exhibit Signup and view all the answers

What is the function of sterocilia?

They have no motility Signup and view all the answers

What is the composition of protofilaments in microtubules?

Tubulin alpha and beta subunits Signup and view all the answers

What is the function of the basal body in a ciliated cell?

To organize the formation of cilia and flagella Signup and view all the answers

What is the structure of the axoneme in flagella and cilia?

9+2 arrangement Signup and view all the answers

What is the characteristic of centrioles?

They are involved in the formation of cilia and flagella Signup and view all the answers

What type of anchoring junctions are responsible for binding cells to the extracellular matrix?

Focal adhesions Signup and view all the answers

What is the function of the cytoplasmic domain of integrins in focal adhesions?

Bind indirectly to actin filaments Signup and view all the answers

Which protein is involved in the attachment of intermediate filaments to hemidesmosomes?

Plectin Signup and view all the answers

What is the consequence of mutations in plectin?

Skin blisters Signup and view all the answers

Which type of collagen is attacked by autoantibodies in bullous pemphigoid?

Type XVII collagen Signup and view all the answers

What is the characteristic of hemidesmosomes?

Single dense plaque Signup and view all the answers

What is the role of integrins in focal adhesions?

Bind to the extracellular matrix Signup and view all the answers

What type of anchoring junctions are involved in cell-cell adhesion?

Desmosomes Signup and view all the answers

What is the main role of cytoplasmic plaque proteins in desmosomes?

To provide attachment sites for intermediate filaments Signup and view all the answers

Which of the following is NOT a cytoplasmic plaque protein?

Desmocollin Signup and view all the answers

What is the main function of desmoplakin in desmosomes?

To provide attachment sites for intermediate filaments Signup and view all the answers

Which of the following cytoplasmic plaque proteins is involved in the attachment of intermediate filaments to desmosomes?

All of the above Signup and view all the answers

What is the consequence of disrupting the cytoplasmic plaque proteins in desmosomes?

Weakened cell adhesion Signup and view all the answers

Which of the following proteins is involved in the attachment of cadherins to intermediate filaments?

Desmoplakin Signup and view all the answers

What is the role of plakophilin in desmosomes?

To provide attachment sites for intermediate filaments Signup and view all the answers

What is the function of fibrin in blood clots?

To form an elastic network Signup and view all the answers

Which of the following is a characteristic of desmosomes?

They contain plaque-shaped structures on the cytoplasmic face Signup and view all the answers

What is the enzyme that cleaves fibrinogen to form fibrin?

Thrombin Signup and view all the answers

What is the function of von Willebrand factor in thrombus formation?

To mediate platelet adhesion Signup and view all the answers

What is the site of storage of von Willebrand factor in endothelial cells?

Weibel–Palade bodies Signup and view all the answers

What is the enzyme that cleaves fibrin to disperse blood clots?

Plasmin Signup and view all the answers

What is the precursor molecule of plasmin?

Plasminogen Signup and view all the answers

What is the function of fibrin in promoting angiogenesis?

By binding to vascular endothelial growth factor Signup and view all the answers

What is the role of tissue plasminogen activator in fibrinolysis?

To activate plasminogen Signup and view all the answers

What is the purpose of the plaque proteins in desmosomes?

To provide attachment sites for intermediate filaments Signup and view all the answers

Which type of junctions are desmosomes?

Desmosomes are anchoring junctions Signup and view all the answers

What is the role of desmoglein and desmocollin in desmosomes?

To link adjacent cells together Signup and view all the answers

In which tissues are desmosomes most abundant?

Skin and heart muscle Signup and view all the answers

What is the result of desmosome disruption in skin autoimmune diseases like Pemphigus?

Disruption of skin epithelial cells Signup and view all the answers

What is the role of desmoplakin in desmosomes?

To provide attachment sites for intermediate filaments Signup and view all the answers

What type of filaments are attached to desmosomes?

Intermediate filaments Signup and view all the answers

What is the function of desmosomes in tissues?

To provide mechanical strength Signup and view all the answers

What type of proteins do Integrins bind to in the basal lamina?

Laminin Signup and view all the answers

What is the characteristic feature of Hemidesmosomes?

Single dense plaque on the cytoplasmic surface Signup and view all the answers

Which type of intermediate filaments is attached to Hemidesmosomes?

Keratin filaments Signup and view all the answers

What is the consequence of autoantibodies attacking Type XVII Collagen in Bullous Pemphigoid?

Skin blisters Signup and view all the answers

Which protein is involved in the attachment of intermediate filaments to Hemidesmosomes?

Plectin Signup and view all the answers

What is the function of Hemidesmosomes?

Cell-matrix adhesion Signup and view all the answers

What is the structure that connects an epithelial cell to the basal lamina?

Hemidesmosome Signup and view all the answers

What is the consequence of mutations in Plectin?

Muscular dystrophy with skin blisters Signup and view all the answers

What is the function of desmosomes in cells?

To provide mechanical binding between adjacent cells Signup and view all the answers

What type of filaments are anchored to desmosomes?

Intermediate filaments Signup and view all the answers

What is the structure of a desmosome?

A button-like point of tight adhesion Signup and view all the answers

What is the role of desmosomes in vertebrate development?

To form the neural tube Signup and view all the answers

What is the function of adherens junctions?

To provide strong adhesion between adjacent cells Signup and view all the answers

What is the role of α-catenin in adherens junctions?

To link actin filaments to cadherins Signup and view all the answers

What is the structure of an adherens junction?

A complex of actin filaments, cadherins, and α-catenin Signup and view all the answers

What is the function of vinculin in adherens junctions?

To anchor actin filaments to the cell membrane Signup and view all the answers

What is the effect of autoantibodies attacking type XVII collagen in bullous pemphigoid?

Causing skin blisters Signup and view all the answers

What is the result of a severe desmoglein 3 deficiency in the skin?

Blistering of the skin with leakage of body fluids Signup and view all the answers

What is the consequence of mutations in plectin?

Skin blisters Signup and view all the answers

Which type of junction is responsible for attaching epithelial cells to the basal lamina?

Hemidesmosomes Signup and view all the answers

Which type of anchoring junctions are responsible for binding cells to the extracellular matrix in skin?

Focal adhesions Signup and view all the answers

What is the function of integrins in hemidesmosomes?

To bind to laminin protein in the basal lamina Signup and view all the answers

What is the role of integrins in focal adhesions in skin?

Binding to the extracellular matrix Signup and view all the answers

What is the function of hemidesmosomes in skin?

Cell-matrix adhesion Signup and view all the answers

What is the consequence of autoantibodies attacking type XVII collagen in bullous pemphigoid?

Skin blistering Signup and view all the answers

Which protein is involved in the attachment of intermediate filaments to hemidesmosomes in skin?

Plectin Signup and view all the answers

What is the result of mutations in plectin?

Late-onset muscular dystrophy Signup and view all the answers

What is the characteristic of hemidesmosomes?

Single dense plaque on the cytoplasmic surface Signup and view all the answers

What is the characteristic of hemidesmosomes in skin?

Having a single dense plaque Signup and view all the answers

Which skin disease is caused by autoantibodies attacking type XVII collagen in the basal lamina?

Bullous pemphigoid Signup and view all the answers

What type of intermediate filaments are involved in hemidesmosomes?

Keratin filaments Signup and view all the answers

What is the function of plectin in hemidesmosomes?

To anchor intermediate filaments to hemidesmosomes Signup and view all the answers

What is the result of desmosome disruption in skin autoimmune diseases like Pemphigus?

The skin epithelial cells become less adherent to each other Signup and view all the answers

Which protein is responsible for the mechanical binding of cells in desmosomes?

Desmoglein Signup and view all the answers

What is the characteristic of desmosomes in skin autoimmune diseases like Pemphigus?

Weaker adhesion between cells Signup and view all the answers

What is the consequence of autoantibodies binding to desmosomal cadherins in Pemphigus?

The skin epithelial cells become less adherent to each other Signup and view all the answers

What is the role of plaque proteins in desmosomes?

To provide attachment sites for intermediate filaments Signup and view all the answers

What is the characteristic of desmosomes in tissues that are exposed to mechanical stress?

They are more abundant Signup and view all the answers

What is the function of desmoplakin in desmosomes?

To provide attachment sites for intermediate filaments Signup and view all the answers

What is the consequence of desmosome disruption in skin autoimmune diseases?

Skin epithelial cells become less adherent to each other Signup and view all the answers

Study Notes

Anchoring Junctions

Anchoring junctions can be subclassified according to the cytoskeletal element that is involved.
There are two types of anchoring junctions:
- Actin filament attachment sites
- Intermediate filament attachment sites

Actin Filament Attachment Sites

Cell-cell junction (ADHERENS JUNCTIONS)
Cell-matrix junctions (FOCAL ADHESIONS)

Intermediate Filament Attachment Sites

Cell-cell junctions (DESMOSOMES)
Cell-matrix junctions (HEMIDESMOSOMES)

Desmosomes

Strongest points of cell adhesion that provide mechanical binding
Most abundant in tissues that are exposed to mechanical stress (epidermis of the skin, heart muscle)
Cell-to-cell binding depends on cadherin family of proteins called desmoglein and desmocollin
Desmosomes contain plaque-shaped structures on the cytoplasmic face of the junction, which provide attachment sites for intermediate filaments
Plaque proteins are plakoglobins, desmoplakins, and plakophilins
Two types of cadherins (desmoglein and desmocollin) link adjacent cells together, and cytoplasmic plaque (desmoplakin, plakoglobin, and plakophilin) links the cadherins
Desmosomes give tissues mechanical strength
Desmosomes are found in many tissues, especially abundant in skin (epidermis), heart muscle, and the neck of the uterus

Importance of Desmosome Junctions

Demonstrated by some of the skin autoimmune diseases, such as PEMPHIGUS
Affected individuals make antibodies against their own desmosomal cadherins, which bind to and disrupt the desmosomes that hold their skin epithelial cells together

Hemidesmosomes

Resemble desmosomes morphologically
Cell uses hemidesmosomes to attach to the basal lamina
Cell-to-matrix adhesion proteins, such as INTEGRINS, are involved in hemidesmosomes
Hemidesmosomes have only a single dense plaque on the cytoplasmic surface of the hemidesmosome (hemi=half) that anchors loops of intermediate filaments
Schematic model of hemidesmosome connecting an epithelial cell to the basal lamina
Extracellular domains of the integrins bind to laminin protein in the basal lamina, and an intracellular domain binds to an anchor protein (plectin) that binds to keratin intermediate filaments

In a blistering skin disease called bullous pemphigoid, autoantibodies attack type XVII collagen
Mutations in plectin cause skin blisters associated with late-onset muscular dystrophy

Focal Adhesions

Bind the cells to the extracellular matrix
Cell-to-matrix adhesion proteins, such as INTEGRINS, are responsible for the binding to the matrix
Cytoplasmic domain of the integrin binds indirectly to actin filaments
Integrin's extracellular domains bind to components of the extracellular matrix, while the cytoplasmic tail of the β subunit binds indirectly to actin

Microvillus Structure

A bundle of parallel actin filaments extend 0.5μ down into the apical cytoplasm and enter into the terminal web
Actin filaments are cross-linked into closely packed bundles by actin-bundling proteins, villin, and fimbrin, forming the core of a microvillus
Actin filaments are attached to the plasma membrane by lateral arms consisting of myosin I and calmodulin
Glycocalix is thicker around the microvilli, forming a striated border, and is PAS+

Cilia and Flagella

Cilia are eyelash or hair-like processes from the cell surface, motile, and longer than microvilli (5-10μ long, 0.2μ in diameter)
Under the electron microscope, they have a complex internal structure composed of microtubules
250 or more cilia are found in each cell, arranged in parallel rows, and function to move fluid over the surface of the cell
Found in epithelial cells of the upper respiratory tract, uterine tubes (oviducts), and efferent ducts (Ductus efferentes)

Basal Body Structure

At the base of a cilium, a central pair of single microtubules terminates
Each of the peripheral doublets is continuous with a triplet microtubule of the basal body
Three microtubules are fused together and form a triplet microtubule
Basal body resembles a centriole but contains some accessory structures such as basal foot and rootlet

Cilia Function

Ciliary movement is important during development
Dynein arms are absent from cilia in patients with Kartagener's Syndrome
Nodal Cilia cannot move during development, and internal organs cannot be located at their normal positions
Helical beating of cilia at the node, and the origins of left-right asymmetry

Flagella Structure and Function

Flagellum propels sperm, is longer than cilia (100-200 μ), and has the same internal structure as cilia (Axoneme 9+2)
Has a different type of movement (undulating wave type of movement) and is less in number (one or two in a single cell)
Mammalian spermium contains 9 additional dense fibers around the axoneme (9+9+2), which serves a protective function

Microtubule Structure

Microtubules are hollow tube-like or pipe-like structures
The wall of the microtubule is composed of 13 protofilaments
Protofilaments are composed of Tubulin subunits (dimer), which consist of Tubulin α and Tubulin β

Gap Junctions

Site of firm adhesion of cells
Allow free interchange of substances
Important role in regulation of intrauterine development and differentiation
Coordinate function among groups of cells

Anchoring Junctions

Two types: Hemidesmosomes and Focal Adhesions

Hemidesmosomes

Have a single dense plaque on the cytoplasmic surface
Anchor loops of intermediate filaments
Integrins bind to laminin protein in the basal lamina
Intracellular domain binds to an anchor protein (plectin) that binds to keratin intermediate filaments
Found in epithelial cells, attach to basal lamina
Mutations in plectin cause skin blisters
Autoantibodies attack type XVII collagen in bullous pemphigoid, a blistering skin disease

Focal Adhesions

Bind cells to the extracellular matrix
Cell-matrix adhesion proteins; integrins responsible for binding to the matrix
Cytoplasmic domain of the integrin binds indirectly to actin filaments
Integrin's extracellular domains bind to components of extracellular matrix
Cytoplasmic tail of the β subunit binds indirectly to actin

Adhesion Proteins

Fibrin: a major ECM component of blood clots
Forms an elastic network to which cells and other ECM components bind
Polymerization of fibrin to form the network occurs when its precursor molecule fibrinogen is cleaved by the enzyme thrombin
Fibrin has binding interactions with various extracellular components, including fibronectin, heparin, growth factors, and cytokines
Fibrinolysis is mediated by plasmin, which cleaves fibrin

Von Willebrand Factor

Plays a key role in the major response of platelets to vascular injury by mediating the initiation and progression of thrombus formation
Enables cell adhesion to develop by forming a bridge between collagen in the vessel wall and blood platelets

Desmosomes

Strongest points of cell adhesion that provide mechanical binding
Most abundant in tissues that are exposed to mechanical stress (epidermis of the skin, heart muscle)
Cell-to-cell binding depends on cadherin family of proteins called desmoglein and desmocollin
Contain plaque-shaped structures on the cytoplasmic face of the junction which provide attachment sites for intermediate filaments
Plaque proteins are plakoglobins, desmoplakins, and plakophilins
Found in many tissues, especially abundant in skin, heart muscle, and the neck of the uterus
Importance of desmosome junctions is demonstrated by some skin autoimmune diseases, such as pemphigus, where affected individuals make antibodies against their own desmosomal cadherins

Desmosomes

Strongest points of cell adhesion that provide mechanical binding
Most abundant in tissues exposed to mechanical stress (epidermis of the skin, heart muscle)
Contain plaque-shaped structures on the cytoplasmic face of the junction, providing attachment sites for intermediate filaments
Plaque proteins include plakoglobins, desmoplakins, and plakophilins
Two types of cadherins (desmoglein and desmocollin) link adjacent cells together
Cytoplasmic plaque (desmoplakin, plakoglobin, and plakophilin) links the cadherins to intermediate filaments

Importance of Desmosomes

Desmosomal cadherins are targeted in autoimmune diseases such as Pemphigus, leading to blistering of the skin
Affected individuals make antibodies against their own desmosomal cadherins, disrupting desmosomes and causing skin epithelial cells to separate

Intermediate Filaments

Types of intermediate filaments include keratin filaments in epithelial cells and desmin filaments in heart and muscle cells
Intermediate filaments can be subclassified according to the cytoskeletal element involved

Anchoring Junctions

Subclassified into two types:
- Intermediate filament attachment sites
  - Cell-cell junctions (desmosomes)
  - Cell-matrix junctions (hemidesmosomes)
- Actin filament attachment sites
  - Cell-cell junctions (adherens junctions)
  - Cell-matrix junctions (focal adhesions)

Hemidesmosomes

Resemble desmosomes morphologically
Cell uses hemidesmosomes to attach to the basal lamina
Contain a single dense plaque on the cytoplasmic surface that anchors loops of intermediate filaments
Schematic model shows an epithelial cell attached to the basal lamina via hemidesmosomes
Autoantibodies attack type XVII collagen in bullous pemphigoid, a blistering skin disease
Mutations in plectin cause skin blisters associated with late-onset muscular dystrophy

Adherens Junctions

Actin filament bundles are attached by intracellular anchor proteins to cadherins
Cadherins are transmembrane proteins that bind to those of adjacent cells, tying actin filament bundles together
Adherens junctions in the form of adhesion belts between epithelial cells in the small intestine
Role in early development: controlled contraction of actin filament bundles causes epithelial cells to narrow and form a tube in vertebrate development

Anchoring Junctions

Anchoring junctions can be subclassified according to the cytoskeletal element involved
Two types of anchoring junctions:
- Actin filament attachment sites
  - Cell-cell junctions (ADHERENS JUNCTIONS)
  - Cell-matrix junctions (FOCAL ADHESIONS)
- Intermediate filament attachment sites
  - Cell-cell junctions (DESMOSOMES)
  - Cell-matrix junctions (HEMIDESMOSOMES)

Desmosomes

Desmosomes are strongest points of cell adhesion that provide mechanical binding
Most abundant in tissues that are exposed to mechanical stress (Epidermis of the skin, heart muscle)
Cell to cell binding depends on cadherin family of proteins called desmoglein and desmocollin
Desmosomes contain plaque-shaped structures on the cytoplasmic face of the junction which provide attachment sites for intermediate filaments
Plaque proteins: plakoglobins, desmoplakins, plakophilins

Hemidesmosomes

Hemidesmosomes resemble desmosomes morphologically
Hemidesmosomes have only a single dense plaque on the cytoplasmic surface of the hemidesmosome (hemi=half) that anchors loops of intermediate filaments
Hemidesmosomes connect epithelial cells to the basal lamina
Integrin (α6β4) and type XVII collagen (also called BPAG2) attach to the basal lamina

Importance of Desmosomes and Hemidesmosomes

In a blistering skin disease called bullous pemphigoid, autoantibodies attack type XVII collagen
Mutations in plectin cause skin blisters associated with late-onset muscular dystrophy
Cataract, heart malformations, and skin blistering are examples of diseases related to desmosome and hemidesmosome dysfunction

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This quiz covers the basics of intermediate filaments and anchoring junctions in cells, including types of filaments and their locations in different cell types.

Medical biology com1 sebnem

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Questions and Answers

What is the result of a severe desmoglein 3 deficiency?

Which type of intermediate filaments is found in epithelial cells?

What is the function of anchoring junctions?

Which type of junctions is involved in cell-cell adhesion?

What is the function of hemidesmosomes?

Which protein is involved in the attachment of intermediate filaments to hemidesmosomes?

What is the consequence of autoantibodies attacking type XVII collagen in bullous pemphigoid?

What is the consequence of mutations in plectin?

What is the function of desmoglein and desmocollin?

What is the result of desmosome disruption in skin autoimmune diseases like Pemphigus?

What type of proteins are desmoglein and desmocollin?

Where are desmosomes most abundant?

What is the role of desmoplakin, plakoglobin, and plakophilin?

What is the purpose of desmosomes?

What is the result of desmoglein and desmocollin binding to anchor proteins?

Where are desmosomes found?

What is the main function of anchoring junctions?

What is the role of integrins in focal adhesions?

What is the consequence of mutations in plectin?

What is the function of hemidesmosomes?

What is the role of the cytoplasmic domain of integrins in focal adhesions?

What type of collagen is attacked by autoantibodies in bullous pemphigoid?

What is the main function of desmoglein and desmocollin?

What is the characteristic of hemidesmosomes?

What is the primary function of microvilli?

What are the proteins that cross-link actin filaments in microvilli?

What is the characteristic of glycocalix around microvilli?

What is the function of cilia in epithelial cells?

Where are cilia typically found in the human body?

What is the structure of cilia composed of?

What is the composition of a triplet microtubule in a basal body?

What is the structure that extends from the basal body into the apical cytoplasm?

What is the function of basal bodies in the organization of cilia and flagella?

What is the difference between a basal body and a centriole?

What is the significance of ciliary movement during development?

What is the characteristic of cilia in patients with Kartagener's Syndrome?

What is the role of nodal cilia in development?

What is the main function of the flagellum in mammalian sperm?

What is the characteristic of microtubules?

What is the significance of the helical beating of cilia at the node?

What is the main difference between flagella and cilia?

What is the function of sterocilia?

What is the composition of protofilaments in microtubules?

What is the function of the basal body in a ciliated cell?

What is the structure of the axoneme in flagella and cilia?

What is the characteristic of centrioles?

What type of anchoring junctions are responsible for binding cells to the extracellular matrix?

What is the function of the cytoplasmic domain of integrins in focal adhesions?

Which protein is involved in the attachment of intermediate filaments to hemidesmosomes?

What is the consequence of mutations in plectin?

Which type of collagen is attacked by autoantibodies in bullous pemphigoid?

What is the characteristic of hemidesmosomes?

What is the role of integrins in focal adhesions?

What type of anchoring junctions are involved in cell-cell adhesion?

What is the main role of cytoplasmic plaque proteins in desmosomes?

Which of the following is NOT a cytoplasmic plaque protein?

What is the main function of desmoplakin in desmosomes?

Which of the following cytoplasmic plaque proteins is involved in the attachment of intermediate filaments to desmosomes?

What is the consequence of disrupting the cytoplasmic plaque proteins in desmosomes?

Which of the following proteins is involved in the attachment of cadherins to intermediate filaments?

What is the role of plakophilin in desmosomes?

What is the function of fibrin in blood clots?

Which of the following is a characteristic of desmosomes?

What is the enzyme that cleaves fibrinogen to form fibrin?

What is the function of von Willebrand factor in thrombus formation?

What is the site of storage of von Willebrand factor in endothelial cells?

What is the enzyme that cleaves fibrin to disperse blood clots?

What is the precursor molecule of plasmin?

What is the function of fibrin in promoting angiogenesis?

What is the role of tissue plasminogen activator in fibrinolysis?

What is the purpose of the plaque proteins in desmosomes?

Which type of junctions are desmosomes?

What is the role of desmoglein and desmocollin in desmosomes?

In which tissues are desmosomes most abundant?

What is the result of desmosome disruption in skin autoimmune diseases like Pemphigus?

What is the role of desmoplakin in desmosomes?