Chapter 5 - Connective Tissue

What structures are pointed by the arrows?

Collagen Fibers This figure shows two images of generic connective tissues. In H&E, type I collagen fibers appear as eosinophilic threads or bands.

True or False. Elastic fibers are extremely strong and resistant to normal shearing and tearing forces.

FALSE Collagen fibers are extremely strong and resistant to normal shearing and tearing forces.

True or False. Fibrils of Type II collagen are bundled together by other forms of non-fibrillar, linking collagens to produce large collagen bundles.

FALSE Fibrils of Type I collagen are bundled together by other forms of non-fibrillar, linking collagens to produce large collagen bundles.

True or False. Fibrocytes in the connective tissue are considered to be "active" cells with abundant rough endoplasmic reticulums (RERs)

FALSE Fibroblasts - are active cells and are abundant in numbers, they possess abundant RERs and are large, ovoid euchromatic nucleus and prominent nucleolus.

True or False Reticular fibers are always visible in hematoxylin and eosin (H&E) preparations.

FALSE Reticular fibers are seldom visible in hematoxylin and eosin (H&E) preparations but are characteristically stained black after impregnation with silver salts and are thus termed argyrophilic.

True or False. Fibroblasts are considered as "transient" cells of the connective tissue.

FALSE Transient cells of the connective tissue: Macrophages Plasma cells Mast cells White blood cells

True or False. GAG's are synthesized in RER

False All other GAGs are much smaller sulfated, bound to proteins (as parts of proteoglycans), and are synthesized in Golgi complexes.

True or False. Dense irregular connective tissue is important in body locomotion and force.

False Dense regular connective tissue provides strong connections within the musculoskeletal system; strong resistance to force.

True or False. Cytokines are secretory substances of the mast cell which acts as an anticoagulant.

False Heparin is a sulfated GAG that acts locally as an anticoagulant.

True or False. Hyaluronate is the smallest and most ubiquitous GAG.

False Largest and most ubiquitous GAG is hyaluronan (also called hyaluronate or hyaluronic acid).

True or False. Dense irregular connective tissue is strong in multiple directions and is usually well vascularized than loose connective tissue.

False Loose (areolar) connective tissue is not very strong, but is usually well vascularized and is found in many locations throughout the body, often serving the role of "filler." Dense irregular connective tissue, on the other hand, is strong in multiple directions, but is usually not as well vascularized as loose connective tissue.

True or False. Osmotic pressure is greater than hydrostatic pressure that is why water passes through capillary walls into the ECM of connective tissues primarily at the arterial end of capillary.

False Water normally passes through capillary walls into the ECM of connective tissues primarily at the arterial end of a capillary, because the hydrostatic pressure is greater than the osmotic pressure. However, hydrostatic pressure decreases toward the venous end of the capillary

These cells produce most, if not all, of the fibers and matrix. What are these cells?

Fibroblasts Fibroblasts are "resident"cells of generic connective tissue. They produce most (if not all) of the fibers and matrix.

What is the pointed structure? What staining is used to visualize this?

Reticular Fibers; Silver Staining The fibers shown are reticular fibers which do not bundle as extensively as collagen fibers, so they are too thin to be seen in routine H&E- stained images. To visualize in light micrographs, special stains, such as silver stains, are used.

True or False. Under the microscope, elastic fibers tend to have a wavy appearance.

TRUE Because elastic fibers recoil during tissue fixation, they tend to have a wavy appearance.

True or False. Interstitial fluid of connective tissues provide metabolic support to cells as a medium for diffusion of nutrients.

TRUE Connective tissue - Provides a matrix that supports and physically connects other tissues and cells to form the organs of the body. Interstitial fluid of CTs - gives metabolic support to cells as medium for diffusion of nutrients and waste products.

True or False. Collagen fibers are mainly synthesized and secreted in fibroblast cells.

TRUE Fibroblasts - Synthesize and secrete collagen (most abundant protein of the body) and elastin, which both form large fibers, as well as the GAGs, proteoglycans, and multi-adhesive glycoproteins that comprise the ground substance.

True or False. All components of the ECM are derived from fibroblasts, especially collagen.

TRUE Fibroblasts - produce and maintain most of the tissue's extracellular components, they synthesize and secrete collagen and elastin which both form large fibers, as well as the GAGs, proteoglycans and multi-adhesive glycoproteins that comprise the ground substance.

True or False. Ligaments and tendons take a long time to heal.

True Because dense regular connective tissue has a sparse blood supply, these tissues (e.g., ligaments, tendons) take a long time to heal

True or False. Proteoglycans have attached GAG's

True Unlike glycoproteins, proteoglycans have attached GAGs that often comprise a greater mass than the polypeptide core.

True or False. Water in the ground substance of connective tissue is called interstitial fluid.

True Water in the ground substance of CT is referred to as interstitial fluid and has an ion composition similar to that of blood plasma

True about reticular fibers a. Abundant in immune and lymphoid tissues b. Contain up to 1% carbohydrate c. Periodic acid-Shiff (PAS) negative due to low content of sugar chains bound to type III collagen α chains d. All of the above

a. Abundant in immune and lymphoid tissues Reticular fibers Delicate fibers which are abundant in immune and lymphoid tissues. Contain up to 10% carbohydrate as opposed to 1% in most other collagen fibers PAS positive, which, like argyrophilia, is due to high content of sugar chains bound to type III collagen α chains

What connective tissue proper can be seen in the dermis of the skin? a. Dense Irregular b. Areolar c. Dense Regular d. Mucoid

a. Dense Irregular Dense irregular connective tissue is composed of little ground substance, few cells (mostly fibroblasts); and much collagen in arranged fibers. It protects and supports organs; and resists tearing. Examples include dermis of the skin, organ capsules, and submucosa layer of digestive tract.

Identify the connective tissue: a. Dense irregular b. Dense regular c. Loose d. Reticular

a. Dense irregular. Another example of dense irregular connective tissue, showing the randomly arranged large collagen bundles. The arrangement of collagen strengthens the tissues and resists tearing from all directions. (X150; H&E) [Junquierra]

Which type of fibers are present in the walls of large blood vessels, which makes them important in blood circulation? a. Elastic b. Reticular c. Collagen d. All of the above

a. Elastic Fibers Elastic fibers are present in the wall of large blood vessels, especially arteries, elastin also occurs as fenestrated sheets called elastic lamella.

Which of the following is true regarding the picture above? a. Figure A- normal, generic connective tissue b. Figure B- normal, multiple fibroblasts seen c. Both are normal d. Both indicate inflammation

a. Figure A- normal, generic connective tissue Connective tissue; green arrows indicate fibroblasts. (b) Inflammation, in which the connective tissue has been "invaded" by WBC (Red arrows mark plasma cells, yellow arrow indicates a neutrophil).

This component of the extracellular matrix (ECM) helps stabilize the ECM by binding it to other matrix components and to integrins in cell membranes. a. Glycoproteins b. Water c. Glycosaminoglycans d. Interstitial projections

a. Glycoproteins Glycoproteins - help stabilize the ECM by binding to other matrix components and to integrins in cell membranes. Water within the ground substance - allows the exchange of nutrients and metabolic wastes between cells and the blood supply.

Which of the following molecules released from mast cells promotes increased vascular permeability and smooth muscle contraction? a. Histamine b. Heparin c. Cytokine d. Serine protease

a. Histamine Histamine: promotes increased vascular permeability and smooth muscle contraction (☤ in recruitment of leukocytes) Heparin: sulfated GAG that acts locally as an anticoagulant Cytokines: polypeptides directing activities of leukocytes and other cells of the immune system Serine proteases: activate various mediators of inflammation

Enzyme that catalyzes the synthesis of hyaluronan a. Hyaluronan Synthase b. Hyaluronan Oxidase c. Hyaluronan Decarboxylase d. Hyaluronan Transaminase

a. Hyaluronan Synthase Hyaluronan is synthesized directly into the ECM by an enzyme complex, hyaluronan synthase, located in the cell membrane of many cells.

The main function of this collagen type is resistance to tension a. I b. II c. III d. IV

a. I Type I Collagen Location: skin, tendon, bone, and dentin Main Function: resistance to tension

What type of connective tissue is the principal component of the fetal umbilical cord (also referred to as Wharton's jelly)? a. Mucoid b. Dense regular c. Loose d. Dense irregular

a. Mucoid Mucoid (or mucous) connective tissue is the principal component of the fetal umbilical cord, where it is referred to as Wharton's jelly. With abundant ground substance composed chiefly of hyaluronan, mucoid tissue is gelatinous, with sparse collagen fibers and scattered fibroblasts.

Long polymers of repeating disaccharide usually a hexosamine and uronic acid a. Mucopolysaccharides b. Ground substance c. Multiadhesive Glycoproteins d. Proteoglycans

a. Mucopolysaccharides GAGs (also called mucopolysaccharides) are long polymers of repeating disaccharide units, usually a hexosamine and uronic acid.

The following are the major products or activities of macrophages except for: a. Pharmacologically active molecules b. Secretion of growth factors and cytokines c. Phagocytosis of ECM components and debris d. Antigen processing and presentation to immune cells

a. Pharmacologically active molecules Pharmacologically active molecules such as histamine are major products of mast cells and basophilic leukocytes

Identify the large, ovoid cells with basophilic cytoplasm. a. Plasma cells b. Leukocytes c. Mast cells d. Macrophage

a. Plasma cells Plasma cells are large, ovoid cells, with basophilic cytoplasm. The round nuclei frequently show peripheral clumps of heterochromatin, giving the structure a "clock-face" appearance.

All of these are functions of adipocytes EXCEPT: a. Stores excess glucose in the liver b. Serves to cushion some organs c. Insulates the skin d. None of the choices

a. Stores excess glucose in the liver Functions of Adipocytes: serves to cushion and insulate the skin and other organs. Adipocytes have major metabolic significance.

Which type of collagen has a main function of resisting pressure? a. Type II b. Type IV c. Type I d. Type III

a. Type II Type II collagen Major location - cartilage, vitreous body Main function - resistance to pressure

These are large, mesenchymal derived cells that are specialized for cytoplasmic storage of lipids as neutral fats. a. Glycogen b. Adipocytes c. Chylomicrons d. VLDL

b. Adipocytes Adipocytes - Large, mesenchymal derived cells are specialized for cytoplasmic storage of lipids as neutral fats, or less commonly to produce heat.

This is the most abundant protein in the body. a. Myoglobin b. Collagen c. Hemoglobin d. Keratin

b. Collagen Collagen is the most abundant protein in the human body, representing 30% of its dry weight.

Identify structure #2: a. Lysosomes b. Collagen Fibers c. Reticular Fibers d. Peroxisomes

b. Collagen Fibers Figure: Electron micrograph of a macrophage, showing (1)lysosomes, (2) collagen fibers, (3) nucleus.

This type of tissue provides a matrix that supports and physically connects other tissues and cells together to form the organs of the body. a. Epithelial tissue b. Connective tissue c. Adipose tissue d. Lymphoid tissue

b. Connective Tissue Connective tissue - connective tissues provides a matrix that supports and physically connects other tissues and cells together to form the organs of the body.

Which of the following is NOT a characteristic event of inflammation? a. Increase blood flow b. Decrease vascular permeability c. Entry and migration of leukocytes d. Activation of macrophages

b. Decrease vascular permeability Characteristic events of inflammation: Increase blood flow and vascular permeability Entry and migration of leukocytes Activation of macrophages for phagocytosis

Identify the connective tissue: a. Dense irregular b. Dense regular c. Loose d. Areolar

b. Dense Regular Micrograph shows a longitudinal section of dense regular connective tissue in a tendon. Long, parallel bundles of collagen fibers fill the spaces between the elongated nuclei of fibrocytes. (X100; H&E stain) [Junquierra]

What connective tissue type provides great resistance to prolonged or repeated stresses from the same direction? a. Dense irregular b. Dense regular c. Areolar d. Loose

b. Dense regular It consists mostly of type I collagen bundles and fibroblasts aligned in parallel for great resistance to prolonged or repeated stresses from the same direction. The best examples of dense regular connective tissue are the very strong and flexible tendons, cords connecting muscles to bones; aponeuroses, which are sheetlike tendons; and ligaments, bands or sheets that hold together components of the skeletal system.

Which type of fiber is mostly seen in the wall of large blood vessels that provide resilience to allow recoil after transient stretching? a. Reticular b. Elastic c. Collagen d. None of the above

b. Elastic Elastic fibers - seen In the wall of large blood vessels, especially arteries, elastin also occurs as fenestrated sheets called elastic lamellae. They have rubber like properties that allow tissue containing these fibers, stroma of the lungs, to be stretched or distended and return to their original shape.

Unlike other tissue types which consist mainly of cells, the connective tissue's major constituent is __________. a. Muscle complex b. Extracellular matrix c. Calcified tissue d. Lymph vessels

b. Extracellular matrix Extracellular matrix - Unlike the other tissue types (epithelium, muscle, and nerve), which consist mainly of cells, the major constituent of connective tissue is the extracellular matrix (ECM). Extracellular matrices consist of different combinations of protein fibers (collagen and elastic fibers) and ground substance.

It provides specific binding sites for integrins and is important both for cell adhesion and cellular migration through the ECM. a. Fibrillin b. Fibronectin c. Aggrecan d. Laminin e. Perlecan

b. Fibronectin The fibronectin substrate provides specific binding sites for integrins and is important both for cell adhesion and cellular migration through the ECM.

It Is highly hydrated, transparent and has a complex of major kinds of macromolecules. a. Mucopolysaccharides b. Ground substance c. Multiadhesive Glycoproteins d. Proteoglycans

b. Ground Substance Ground substance of the ECM is a highly hydrated (with much bound water), transparent, complex mixture of three major kinds of macromolecules: glycosaminoglycans (GAGs), proteoglycans, and multi-adhesive glycoproteins.

Which antibody is important in anaphylaxis? a. IgA b. IgE c. IgG d. IgM

b. IgE Anaphylaxis: The first exposure to an antigen (allergen), such as bee venom, causes antibody-producing cells to produce an immunoglobulin of the IgE class that binds avidly to receptors on the surface of mast cells.

What is true about the one that forms a layer beneath the epithelial lining of many organs and fills the spaces between fibers of muscles and nerves? a. It has bundled Type I Collagen fibers predominance b. It is called Areolar Connective Tissue c. It contains Type III Collagen d. It is called Dense Connective Tissue

b. It is called Areolar Tissue Areolar Tissue is another term for Loose Connective Tissue.

Mesenteries are examples of what type of connective tissue? a. Dense regular b. Loose c. Dense irregular d. Adipocytes

b. Loose Many organs are suspended within the peritoneal cavity by mesenteries. They are examples of loose (areolar) connective tissue.

Which cell is matched correctly with its major location and main function? a. Osteoclast: bone - segregation and digestion of foreign bodies b. Macrophage: connective tissue, lymphoid organs, lungs and bone marrow - production of cytokines, chemotactic factors, and several molecules that participate in inflammation c. Dendritic cell: central nervous system - antigen processing and presentation d. Multinuclear giant cell: blood - precursor of macrophages

b. Macrophage: connective tissue, lymphoid organs, lungs and bone marrow - production of cytokines, chemotactic factors, and several molecules that participate in inflammation Osteoclast: bone - localized digestion of bone matrix Dendritic cell: lymph nodes, spleen - antigen processing and presentation Multinuclear giant cell: in connective tissue under various pathological conditions - segregation and digestion of various bodies

This type of fibroblast have well-developed contractile function which aids in wound healing or tissue repair. a. Cryofibroblasts b. Myofibroblasts c. Ectofibroblasts d. Xenofibroblasts

b. Myofibroblasts Myofibroblasts - features of both fibroblasts (mostly) and smooth muscle cells (increased amounts of actin microfilaments and myosin) called myofibroblast are observed in some rapidly closing wounds. It is also important in wound contraction, phase of tissue repair.

True about proteoglycan's locations of synthesis, maturation and its secretion. a. Proteoglycans are synthesized in SER, matures in the Golgi Apparatus and secreted from cells by exocytosis b. Proteoglycans are synthesized in RER, matures in the Golgi Apparatus and secreted from cells by exocytosis c. Proteoglycans are synthesized in SER, matures in the Golgi Apparatus and secreted from cells by endocytosis d. Proteoglycans are synthesized in RER, matures in the Golgi Apparatus and secreted from cells by endocytosis

b. Proteoglycans are synthesized in RER, matures in the Golgi Apparatus and secreted from cells by exocytosis Like glycoproteins, they are synthesized on RER, mature in the Golgi apparatus, where the GAG side chains are added, and secreted from cells by exocytosis.

Elastic fibers (and lamellae) are composed of which type of protein(s)? a. Elastin b. Fibrillin c. All of the above d. None of the above

c. All of the above Elastic fibers, or sheets called elastic lamellae, are composed of the proteins elastin and fibrillin, which exist in a stretchable conformation that provide elastic properties to connective tissues rich in this material.

What do you call a phenomenon where specific cell type are attracted by specific molecules, which draws much larger numbers of leukocytes into inflamed tissues? a. Edema b. Phagocytosis c. Chemotaxis d. Anaphylaxis

c. Chemotaxis Chemotaxis - phenomenon where specific cell types are attracted by specific molecules, draws much larger numbers of leukocytes into inflamed tissues.

A pro soccer player injured an important ligament in his knee part, what is the correct description of the injured part it is at? a. Loose connective tissue b. Areolar connective tissue c. Dense regular connective tissue d. Dense irregular connective tissue

c. Dense regular connective tissue It consists mostly of type I collagen bundles and fibroblasts aligned in parallel for great resistance to prolonged or repeated stresses from the same direction. The best examples of dense regular connective tissue are the very strong and flexible tendons, cords connecting muscles to bones; aponeuroses, which are sheetlike tendons; and ligaments, bands or sheets that hold together components of the skeletal system.

Which collagen fiber is not formed by proteins of the collagen family? a. Collagen b. Reticular c. Elastic d. None of the above

c. Elastic Collagen and reticular fibers are both formed by proteins of the collagen family. Elastic fibers are composed mainly of the protein, elastin.

Functions of Ground Substance? I. Allows diffusion of large molecules II. Acts as a lubricant III. Acts as a barrier IV. Allows diffusion of small molecules a. I & II b. I,II,III c. II,III,IV d. II&III e. I,III,IV

c. II, III, IV Filling the space between cells and fibers in CT, ground substance allows diffusion of small molecules and, because it is viscous, acts as both a lubricant and a barrier to the penetration of invaders.

What cells numerous in loose connective tissue are filled with secretory granules and stain with metachromasia? a. Macrophages b. Fibrocytes c. Mast cells d. Leukocytes

c. Mast cells Mast cells have high content of acidic radicals in their sulfated GAGs, mast cell granules display metachromasia, which means that they can change the color of some basic dyes (eg, toluidine blue) from blue to purple or red.

All connective tissues arise from what type of embryonic tissue? a. Endoderm b. Mesothelium c. Mesenchyme d. Ectoderm

c. Mesenchyme Embryonic Mesenchyme - all CTs originate from embryonic mesenchyme, a tissue developing mainly from the middle layer of the embryo, mesoderm. Mesenchymal cells are undifferentiated and have large nuclei, with prominent nucleoli and fine chromatin.

Large molecules with branched oligosaccharide chains and allows adhesion of cells to their substrate. a. Mucopolysaccharides b. Ground substance c. Multiadhesive Glycoproteins d. Proteoglycans

c. Multiadhesive Glycoproteins The adhesive glycoproteins are large molecules with branched oligosaccharide chains and allow adhesion of cells to their substrate. Example is the large trimeric glycoprotein laminin with binding sites for integrins, type IV collagen, and specific proteoglycans, providing adhesion for epithelial and other cells. Another glycoprotein is fibronectin which is a dimer synthesized largely by fibroblasts, with binding sites for collagens and certain GAGs, and forms insoluble fibrillar networks throughout CT

When macrophages are stimulated either by an injection of foreign substances or by infection, they change their morphologic characteristics and properties. Which of the following are not evident when macrophages become activated macrophages? a. Increase in capacity for phagocytosis and intracellular digestion b. Increase in size and fuse to form multinuclear giant cells c. None of the choices d. All of the choices

c. None of the choices Activated macrophages exhibit enhanced metabolic and lysosomal enzyme activity and when adequately stimulated, macrophages may increase in size and fuse to form multinuclear giant cells, usually found only in pathologic conditions.

All of these are components of the ECM's ground substance EXCEPT: a. Multiadhesive glycoproteins b. Anionic & Hydrophilic proteoglycans c. Proteolytic enzymes d. Glycosaminoglycans

c. Proteolytic enzymes Ground substance - is a complex of anionic, hydrophilic proteoglycan, glycosaminoglycans (GAGs), and multi-adhesive glycoproteins (laminin and fibronectin).

Identify the pointed structure: a. Lysosomes b. Peroxisomes c. Secretory granules d. None of these

c. Secretory Granules Figure: Electron micrograph of a mast cell with secretory granules (red arrows) The components of the secretory granules in mast cells demonstrate a specific type of staining quality called metachromasia, in which the components of a cell or tissue changes the original color of a dye.

Which type of collagen is the most abundant and widely distributed? a. Type III b. Type II c. Type I d. Type IV

c. Type I Collagen type I - most abundant and widely distributed collagen which forms large eosinophilic bundles (collagen fibers). These often densely fill the connective tissue, forming structures such as tendons, organ capsules, and dermis.

Reticular fibers are mainly made up of which type of collagen fibers? a. Type II b. Type I c. Type III d. Type IV

c. Type III Found in delicate CT of many organs, notably in the immune system, reticular fibers consist mainly of collagen type III.

The tissue pointed by arrows in the following image is primarily composed of what type of collagen fibers? a. Type I b. Type II c. Type III d. All of these

c. Type III Reticular tissue is characterized by abundant fibers of type III collagen.

Collagens secreted by other cell types and are distinguishable by their: a. Pathologies b. Morphologic characteristics c. Functions d. All of the above

d. All of the above Collagens are also secreted by several other cell types and are distinguishable by their: Molecular compositions Morphologic characteristics Distribution Functions Pathologies

Identify the type of connective tissue: a. Dense irregular b. Dense regular c. Collagen d. Areolar

d. Areolar (or Loose Connective Tissue) The outlined part in the image is an example of loose connective tissue from the inner lining of the heart stained with Gomori trichrome stain, which highlights collagen (green). Nuclei in this image are red.

In Dense Connective Tissue, the abundance of _________ protects organs and strengthens them structurally. a. Ground Substance b. Elastin c. Reticulin d. Collagen

d. Collagen There is a predominance of bundled type I collagen fibers over ground substance in Dense Connective Tissue.

Which type of connective tissue is strong in ONE direction but is poorly vascularized? a. Loose b. Dense irregular c. Cartilage d. Dense regular

d. Dense regular Dense regular is strong in ONE direction while dense irregular is strong in MULTIPLE directions. Similarly, both are poorly vascularized.

Identify the pointed structures: a. Chondrocyte b. Monocyte c. Fibrocyte d. Fibroblast

d. FIBROBLASTS Fibroblasts typically have large active nuclei and eosinophilic cytoplasm that tapers off in both directions along the axis of the nucleus, a morphology often referred to as "spindle-shaped".

Fibroblasts synthesize and secrete all of these substances of the ECM EXCEPT: a. Elastin b. Glycosaminoglycans c. Collagen d. Integrins

d. Integrins Fibroblasts - synthesize and secrete collagen and elastin which both form large fibers, as well as the GAGs, proteoglycans and multi-adhesive glycoproteins that comprise the ground substance.

What is the function of Eosinophilic Leukocytes? a. Phagocytosis of Bacteria b. Phagocytosis of ECM components and debris c. Storage of neutral fats d. Modulate allergic/vasoactive reactions and defense against parasites

d. Modulate allergic/vasoactive reactions and defense against parasites A- Neutrophilic Leukocytes B- Macrophages C- Adipocytes

Which of the statement(s) is/are correct? I. Hydrostatic pressure draws water back into the capillaries II. Colloid Osmotic Pressure forces water out across the capillary wall a. I only b. II only c. Both are true d. Neither are true

d. Neither are true Hydrostatic pressure of blood caused by the pumping action of the heart, which forces water out across the capillary wall. Colloid osmotic pressure produced by plasma proteins such as albumin, which draws water back into the capillaries.

All of these are considered cells of the connective tissue EXCEPT: a. Plasma cells b. Mast cells c. Fibroblasts d. Osteoblasts

d. Osteoblasts Cells of the Connective Tissue: Fibroblasts Macrophages Plasma cells Mast cells White blood cells

Consists of a core protein to which are covalently attached various numbers and combinations of the sulfated GAG's a. Mucopolysaccharides b. Ground substance c. Multiadhesive Glycoproteins d. Proteoglycans

d. Proteoglycans Proteoglycans consist of a core protein to which are covalently attached various numbers and combinations of the sulfated GAGs.

Which of the following describes plasma cells? a. Very large cells specialized for storage of triglycerides b. Function in ECM turnover, phagocytosis of dead cells and debris, and antigen presentation to lymphocytes c. Are filled with granules for the release of various vasoactive agents and other substances during inflammatory and allergic reactions d. Specialized for the abundant secretion of specific antibodies (immunoglobulins)

d. Specialized for the abundant secretion of specific antibodies (immunoglobulins) Adipocytes are very large cells specialized for storage of triglycerides. Macrophages function in ECM turnover, phagocytosis of dead cells and debris, and antigen presentation to lymphocytes. Mast cells are filled with granules for the release of various vasoactive agents and other substances during inflammatory and allergic reactions.

Major GAG's found in proteoglycans I. Dermatan Sulfate II. Keratan Sulfate III. Heparan Sulfate IV. Hyaluronan Sulfate V. Chondroitin Sulfate a. V,II,IV,III b. IV, I, III, V c. IV, III, II, I d. V, II, III, I

d. V, II, III, I The four major GAGs found in proteoglycans are: Dermatan sulfate, Chondroitin sulfates, Keratan sulfate, and Heparan sulfate. All of which have different disaccharide units modified further with carboxyl and sulfate groups and different tissue distributions.