histology ch.4

secretion involves loss of membrane-enclosed apical cytoplasm, usually containing one or more lipid droplets.

apocrine

what proteins seal adherent or anchoring junction

cadherin

what tissue is the stroma

connective except brain and spinal cord

what protein do gap junctions use

connexons

do exocrine or endocrine contain myeopethelial cells

exo

are channels for communication between adjacent cells.

gap junctions

are sites of strong cell adhesion.

Adherent or anchoring junctions

both of these cross-link laminin to the collagen network and help determine the porosity of the basal lamina and the size of molecules able to filter through it.

Nidogen and perlecan

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? a. Desmosomes b. Tight junctions c. Hemidesmosomes d. Gap junctions e. Reticular lamina

a

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? a. Microvilli b. Gap junctions c. Cilia d. Cell layers e. Basement membrane thickness

a

a. Material crossing the epithelium between the cells (paracellular movement) b. Communication between the cells c. Attachment to the basement membrane d. Strong attachment to neighboring cells e. Movement of membrane proteins in the apical domains of cells

a

what kind of junction is desmosome

anchoring junction

Functions of the basement membrane include which of the following? a. Contractility b. Molecular filtering c. Active ion transport d. Excitability e. Modification of secreted proteins

b

Which of the following cellular features is used in naming types of epithelia? a. Shape of cells in the basal layer b. Number of cell layers c. Presence of a basal lamina d. Size of the nuclei e. Nature of the cell junctions that are present

b

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? a. Hemidesmosomes b. Cilia c. Basolateral cell membrane folds d. Microvilli e. Tight junctions

b

The region of the cell contacting the ECM and connective tissue is called the _____________ and the opposite end, usually facing a space, is the _____________

basal pole apical pole,

Exocrine glands in which the acini all produce a secretion of heavily glycosylated, hydrophilic proteins are an example of which type of gland? a. Serous gland b. Mixed gland c. Mucous gland d. Tubuloacinar gland e. Simple gland

c

The release of lipid droplets from cells is which type of secretion? a. Merocrine b. Serous c. Apocrine d. Mucous e. Holocrine

c

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? a. Tight (occluding) junctions b. Zonula adherens c. Gap junctions d. Hemidesmosomes e. Desmosomes (macula adherens)

c

in tight junction The seal between the two cell membranes is due to tight interactions between the transmembrane proteins

claudin and occludin

An intermediate filament protein found in cytoplasm of most epithelial cells is which of the following? a. Actin b. Vimentin c. Laminin d. Myosin e. Keratin

e

_____________bind the basal surface of the epithelial cell (C) to the basal lamina.

hemidesomosomes

secretion is produced by the disintegration of the secretory cells themselves as they complete their terminal differentiation, which involves becoming filled with product.

holocrine

The connective tissue that underlies the epithelia lining the organs of the digestive, respiratory, and urinary systems is called

lamina propria

These are large glycoproteins that attach to transmembrane proteins called integrins at the cells' basal surface and project through the network of type IV collagen.

laminin

secretion releases products, usually containing proteins, by means of exocytosis at the apical end of the secretory cells.

merocrine

what lines the small intestine and help with absorption

microvilli

what contains heavily glycosylated proteins

mucuous

The area of contact between the two tissues may be increased by small evaginations called

papillae

cells responsible for the organ's specialized functions

parenchyma

psuedostratified columnar epithelium

part of respiratory tract, includes a mixture of cell types

what collagen does reticular and basal lamina have

reticular: type 3 basal: type 4

cells of which have a supporting role in the organ

stroma

what sensory cell is in the inner ear

sttereocilia

form a seal between adjacent cells.

tight or occluding junctions