Epithelial/Connective Tissue
Name two changes in respiratory tract cells associated with chronic bronchitis.
-Increase in number of goblet cells -Conversion of ciliated pseudostratified epithelium into stratified squamous epithelium.
Proteoglycans characteristic:
A core protein with a variety of sulfrated GAGs attached to it
The release of lipid droplets from cells is which type of secretion?
Apocrine
Which of these is not classified as a connective tissue?
Arteries and veins
Which is the function of hemidesmosomes?
Attach epithelial cells to basement membrane
The two layers of the basement membrane are the:
Basal lamina and reticular lamina
What separates the sheet of epithelial cells from other tissues?
Basement membrane
Which of these tissues does not contain collagen (or only minute amounts)?
Blood
Edema is the excessive accumulation of interstitial fluid in connective tissue. Where does this fluid come from before it accumulates in the connective tissue?
Blood.
A malignant tumor of epithelial origin is a
Carcinoma
Which one of these is not one of the four major tissue types? Epithelial Tissue Nervous Tissue Connective Tissue cardiac tissue
Cardiac Tissue
Which of these apical specializations functions primarily in movement of extracellular substances?
Cilia
With a 5-year history of chronic respiratory infections, a 23-year-old, non-smoking man is referred to an otolaryngologist. A bronchial biopsy indicates altered structures in the epithelial cells. Which of the following, if altered to reduce function, is most likely involved in this patient's condition?
Cilia
Scar tissue is composed of what types of fibers?
Collagen
What is the most abundant protein in the human body?
Collagen
Which type of fibers are tendons composed of?
Collagen
The two major types of protein fibers in the ECM are
Collagen and elastic
Which of the following connective tissue components is located in the ECM but not in the ground substance?
Collagen bundles
A 36-year-old man is referred by his family physician to the pulmonary clinic. He complains of shortness of breath following physical activity and decreased capacity for exercise. He says that strenuous exercise including yard work is impossible without sitting down and resting every few minutes. After taking several deep breaths during the physical examination, he begins to wheeze. He is not a smoker and works in an office not exposed to dust, fumes, or other irritants. He appears slightly jaundiced. Serum alpha-1-antitrypsin (AAT) concentration analysis is below normal and is followed up with AAT phenotype and DNA testing which indicates one copy of S and one of Z mutations with 40% abnormal AAT production. Urinalysis shows elevated levels of desmosine and isodesmosine. These excreted compounds normally contribute to efficient lung function by which of the following mechanisms?
Cross-linking elastin
Simple branched acinar location:
Cutaneous sebaceous glands
What is the name for the complex array of microtubules, microfilaments, and intermediate filaments in the cytoplasm of the cell?
Cytoskeleton
Leather is composed primarily of
Dense irregular connective tissue
The dermis of the skin contains which type of connective tissue proper?
Dense irregular connective tissue
Aponeuroses are composed of which type of connective tissue proper?
Dense regular connective tissue
A 42-year-old woman of Mediterranean descent presents with multiple oral blisters and a few cutaneous blisters on her back and buttocks. The superficial bullae are fragile, some have unroofed to form ulcerated lesions, and there is a positive Nikolsky sign. Blood tests reveal antibodies to a subfamily of cadherins and immunohistochemical staining of a biopsy from the oral mucosa shows distribution of the antigen throughout the epithelium. In what structures is the defect that is causing this patient's condition?
Desmosomes
What condition is produced by increased blood flow and vascular permeability?
Edema
Nervous Tissue characteristic:
Elongated cells bearing long, thin processes
Muscle Tissue characteristic:
Elongated, contracted cells
A severe allergic reaction is associated with the rapid release of histamine, leukotrienes, and chemokines from the mast cell granules. Which of these substances below is commonly used to counteract this reaction?
Epinephrine
What causes acne?
Excessive secretion of the sebaceous glands.
Where is stratified cuboidal epithelium found?
Excretory ducts of salivary and sweat glands.
A major difference between exocrine and endocrine glands is that
Exocrine glands have ducts and endocrine glands do not.
Compound Acinar location:
Exocrine pancreas
The major component of connective tissue is
Extracellular Matrix (ECM)
Elastic fibers are formed from two proteins:
Fibrillin and elastin
What types of cells are indicated by the dark purple nuclei?
Fibroblasts
Fibroblasts are an important cell type in connective tissue. They synthesize collagen and elastin, as well as the three major macromolecules in ground substance. How do fibroblasts differ from macrophages and mast cells?
Fibroblasts originate from mesenchymal cells, whereas the others originate from stem cells in bone marrow.
Which of the following contains binding sites for integrins and is an important part of the ECM in both loose connective tissue and dense irregular connective tissue?
Fibronectin
A 33-year-old homeless woman has been living in an abandoned building eating dried meat and bread from the dumpster behind a delicatessen. She smokes cigarettes "bummed" from others. She presents at a free clinic with bleeding under the skin, particularly around hair follicles, and bruises on her arms and legs. She is irritable, clinically depressed, and fatigued with general muscle weakness. Her gums are bleeding, swollen, purple, and spongy, with several loose teeth. She has an infected toe, which may be broken. She is afebrile, a glucose finger-stick is normal, and the urine dipstick shows no sugar, protein, or ketones. You suspect a vitamin deficiency. What might be the underlying mechanism for this patient's symptoms?
Formation of unstable collagen helices
Using immunohistochemistry a population of cells is shown to be positive for the protein connexin. From this we can infer that the cells are connected by what type of junction?
Gap junctions
Loss of the microvilli of absorptive cells in the small intestine may be caused by
Gluten-sensitive enteropathy
What is the name for the unicellular glands that secrete lubricating mucus?
Goblet cells
What are the two main components of extracellular matrix?
Ground Substance and Protein Fibers
Keratinized cells are packed with filaments of keratin, which is a protein. Which of these materials also is composed primarily of keratin?
Hair
Which of these is not a function of macrophages?
Hemopoiesis
Which type of secretion do sebaceous glands have?
Holocrine
Research scientists at a small biotech firm are investigating new methods of controlling the growth and metastasis of malignant cells in patients diagnosed with breast cancer. They have developed a novel peptide-based drug, potentially deliverable therapeutically, that disrupts the tumor cells' ability to adhere to the ECM, which in turn triggers apoptosis. Which of the following is a most likely target of such drugs?
Integrins
Holocrine secretion
Involves cell disruption
What is a keloid?
It is a local swelling caused by abnormally large amounts of collagen that form in scars of the skin.
Which of these is a diagnostic or necessary characteristic of simple epithelium?
It is composed of a single cell layer.
What is interstitial fluid?
It is water in the ground substance of connective tissue.
One feature of urothelium is that:
It lines much of the urinary tract.
An intermediate filament protein found in cytoplasm of most epithelial cells is which of the following?
Keratin
Glycosaminoglycans (GAG) characteristic:
Long unbranched chains of repeating disaccharide units
One major function of connective tissue proper is to physically support and connect other tissues. A second major function is to
Maintain water as interstitial fluid for nutrient and metabolite diffusion, using hydrostatic and osmotic pressure.
Which of these cell types triggers allergic reactions by secretion of several types of substances?
Mast Cells
What cells numerous in loose connective tissue are filled with secretory granules and stain with metachromasia?
Mast cells
An individual genetically unable to synthesize normal occludin is likely to have epithelia with defective regulation in which of the following?
Material crossing the epithelium between the cells (paracellular movement)
Mesenchyme is an embryonic tissue composed of undifferentiated cells that have the ability to produce connective tissue proper, bone, cartilage, and muscle, among others. From which major embryonic tissue is mesenchyme derived?
Mesoderm
An 11-month-old girl is referred to a pediatric gastroenterology clinic due to a history of generalized weakness, slow growth, and refractory diarrhea. For the past month she has been hospitalized regularly to receive parenteral nutrition. Examination of the epithelium lining her small intestine confirms that the failure to absorb nutrients is most likely due to a significant decrease in which of the following?
Microvilli
The brush border is formed by
Microvilli of intestinal epithelial cells
Functions of the basement membrane include which of the following?
Molecular filtering
Another name for GAGs is
Mucopolysaccharides
What substance do goblet cells secrete?
Mucous
Exocrine glands in which the acini all produce a secretion of heavily glycosylated, hydrophilic proteins are an example of which type of gland?
Mucous gland
Simple tubular location:
Mucous glands of colon
Serous glands produce mostly:
Non-glycosylated proteins
Which of the following cellular features is used in naming types of epithelia?
Number of cell layers
The intercellular seal of tight junctions ensures that molecules crossing an epithelium in either direction do so by going through the cells rather than between them. This path between the cells is called the
Paracellular pathway
Antibodies are glycoproteins of the immunoglobulin family that interact with specific antigens. Which type of cells produce antibodies?
Plasma cells
What word describes the fact that epithelial cells have an apical pole and a basal pole?
Polarity
Epithelial Tissue characteristic:
Polyhedral cells forming sheets
Dense regular connective tissue typically involves which of the following features?
Predominantly located in tendons and ligaments
What is the function of mucoid connective tissue?
Protection of blood vessels in the umbilical cord.
Which type of molecule are epithelial cell junctions made of?
Proteins
Sulfated GAGs are important constituents of what extracellular structures?
Proteoglycans
What is the first step of collagen production that occurs after the protein undergoes exocytosis?
Removal of the terminal nonhelical domains by peptidases
Compound tubuloacinar location:
Salivary glands
What is an important part of the role played by macrophages during maintenance and renewal of strong extracellular fibers in connective tissue?
Secretion of matrix metalloproteinases
Endothelium is a type of epithelial tissue that lines the inner surface of blood vessels, and regulates passage of substances into the tissue below. Endothelium is composed of cells with what type of arrangement and shape?
Simple squamous
Mutations in the genes that code for the proteins composing the hemidesmosome are linked to disorders such as
Skin blistering
Multiadhesive glycoproteins. characteristic:
Small glycosylated proteins with many binding sites for other molecules
The 9 + 2 axoneme of a cilium is very similar to the flagellum that is found in
Sperm cells
Which one correctly characterizes stereocilia?
Stereocilia are less common on tissues than cilia are, they are not actively motile, and they are longer than microvilli.
Given the structure of a cilium, you would not expect to find cilia on which of these types of epithelial tissue?
Stratified squamous keratinized epithelium
What is the function of the adherent junctions?
Strengthen adjacent tight junctions
Connective tissue forms the ________________of many organs.
Stroma
Coiled tubular location:
Sweat glands
The secretory cells of ____________glands secrete mostly water and ions
Sweat glands
In the presence of an allergen (which can from any of a number of things such as insect venom, peanuts, penicillin, etc.), release of certain chemicals from mast cells may promote an allergic reaction known as an immediate hypersensitivity (also called Type I hypersensitivity) reaction. How is this reaction different from the normal infectious immune response of mast cells?
The immediate hypersensitivity reaction typically requires a previous sensitization to the allergen.
Mucus is formed by hydrated mucins, which in turn are glycosylated proteins. What is glycosylation?
The process of adding a polysaccharide to another molecule such as a protein or lipid.
Which of these is not true of myoepithelial cells?
They are derived from myoblasts, the precursors of muscle cells.
What do these cell types have in common: Microglia, osteoclasts, and Kupffer cells.
They are part of the mononuclear phagocyte system.
The toxin secreted by Clostridium perfringens binds proteins associated with ________________, and causes loss of tissue fluid into the intestinal lumen.
Tight junctions
Connective Tissue characteristic:
Various kinds of fixed and wandering cells
The simple and compound gland types are distinguished according to what criterion?
Whether or not the ducts branch
Merocrine secretion
involves exocytosis
Apocrine secretion
involves extrusion