TOB Flashcards
What is a biopsy?
Removal of a small piece of tissue from an organ for microscopic investigation
Define histology
Study of the structure of cells by means of staining and light microscopy techniques
Why is a tissue fixed?
Prevent autolysis and putrefaction
Maintain cross-linked macromolecules
Outline the process of tissue fixation
Dancing xylophones ecstatically sway randomly. Swaying demands men. Dehydration using ethanol Xylene used to wash Embedded in wax Sectioned Rehydrated Stained Dehydration again Mount specimen on a slide
Define epithelia
Sheets of contiguous cells, of varied embryonic origin which cover the external surface of the body and line internal surfaces
What are the main features of the basement membrane?
Thin, flexible, acellular layer which lies between epithelial cells and underlying connective tissue layer. Acting as a strong layer that epithelial cells can adhere to and a cellular and molecular filter
Mesothelium
Simple squamous epithelium lining body cavities
Sites of simple cuboidal epithelium
Kidney tubules
Thyroid follicles
Pancreatic duct
How is cilia structure related to function?
Numerous mitochondria for ATP synthesis to allow synchronous peristaltic waves.
Describe and explain the importance of glycosylation in the Golgi
O linked glycosylation of proteins by glycosyl transferase with addition of branching sugars to produce glycocalyx of cell membrane.
Needed for-
Adhesion to substrates and neighbouring cells
Mobility of cells
Communication with neighbouring cells
What is produced by exocrine pancreas?
Pancreatic amylase, lipase, trypsinogen (trypsin zymogen)
Define mucous membrane
Give examples
Membrane lining surfaces opening to the exterior, consisting of epithelia and lamina propria.
Example of place it is found is alimentary tract (where there is also a layer of smooth muscle- muscularis mucosae)
Define serous membrane
Lines internal body cavities not opening to the exterior. Consists of simple squamous epithelia and a thin layer of connective tissue which carries blood vessels and nerves and connects epithelia to adjacent tissues
Where are the plicae circulares found?
What are they?
Found in jejunum
Circular folds projecting into lumen of the small intestine
What are the layers of muscularis externa found in the bladder?
Inner- circular
Middle- longitudinal
Outer- oblique
What 3 components make up cell cytoskeleton?
Microfilaments
Microtubules
Intermediate filaments
What are the three functions of plasma membrane?
Selective permeability
Cell morphology and movement
Transport of substances
Function of lysosomes
Digestion of cell debris and waste material
Fuse with material requiring digestion and then secrete hydrolytic enzymes
Function of nucleolus
Ribosome assembly and RNA modification
Define connective tissue
Forms a continuum throughout the body which links muscle, nerve and epithelial tissue in a supportive, structural, metabolic and physical way
5 types of connective tissue
Blood Cartilage Bone Adipose Fibrocollagenous
Resident cells of connective tissue
Macrophages digest foreign material and are professional antigen presenting cells (inflammation)
Fibroblasts secrete amorphous extracellular matrix and fibres within it (mainly collagen)
Mesenchyme- undifferentiated cells which maintain extracellular matrix
Visitant cells in connective tissue
Mast cells surround blood vessels and secrete heparin and histamine
Adipocytes
leukocytes production of immunocompetent cells
Plasma cells derived from lymphocytes
Name the 4 different types of loose connective tissue
Mucous (whartons jelly)
Adipose
Areolar
reticular
