Glands Flashcards
Define what a Gland is
An epithelial cell or aggregate of cells specialised for secretion
Name the three salivary gland. (From front of face to back)
Sublingual, Submandibular, Parotid
Define exocrine glands
Secrete contents via ducts onto an epithelial surface
Define endocrine glands
‘Ductless’ secrete directly into the bloodstream
Difference between mucous and serous secretions
Mucous is rich in mucins (glycosylated polypeptides)
Serous- watery secretions with enzymes
Which, out of mucous and serous cells, stain better with H&E?
Serous stain dark pink (eosin TF must be basic)
Mucous stain poorly
What is the most common way in which glands secrete? Describe how it works
Merocrine, membrane bound structure fuses with apical plasma membrane of cell and contents are released into extra cellular space. Membrane is slightly larger as a result.
What is apocrine secretion?
Non-membrane bound structures bind to apical plasma membrane and push it up. A think layer of the membrane wraps around the droplet and pitches off. Membrane is slightly smaller as a result.
What is holocrine secretion? Give an example
Where the cell disintegrates to release the contents within. Eg- sebaceous sweat glands
Give an example of apocrine secretion
Mammary glands, sweat glands in certain areas (axilla, areola, genitals, perineal etc)
List 4 ways secretion can be controlled
Nervous, endocrine, neuro-endocrine, negative feedback
List the purely exocrine glands
Parotid, submandibular, goblet cells
List the glands that are both exo and endo
Pancreas, liver
List the glands that are purely endocrine
Thyroid, adrenal, parathyroid
What is the alternative name for adrenal glands?
Suprarenal
What is the exocrine function of the pancreas?
Secrete ~1L of alkaline digestive fluid a day
Exocrine function of liver?
Secrete ~1L of bile a day into the duodenum
Which is the largest gland in the body? Describe where it is
Liver, upper RH portion of abdominal cavity, beneath the diaphragm, above the stomach
Which of the salivary glands secretes the most salvia?
Submandibular
What type of secretions does parotid gland secrete?
Only serous, they contain enzyme amylase
What type of secretions does the submandibular gland secrete?
Serous and mucous
What is the name of the type of artefacts present when fixing a certain salivary gland? Which gland is it?
Submandibular- serous demilunes. When freezing occurs, serous cells ‘squash out’ and form crescent shapes
Describe histological appearance of pancreas
Islets of Langherhans surrounded by exocrine acini. Islets of Langerhans are lighter staining, exocrine cells are darker staining.
Where is the pancreas situated?
Behind the stomach, in the curve of the duodenum