Exocrine And Specialised Glands Flashcards
Where are the main reference points in the location of the parotid gland?
Parotid=next to ear
Points= head of mandible, mastoid process (bottom of ear), middle of masseter, and 2cm below the angle of mandible
What cells make up the parotid gland?
It’s a serous gland so manly serous cells (no visible lumen), very few mucus cells a few striated ducts. Also zygotes granules containing amylase.
The 3 salivary glands have different ratios of serous and mucus cells state them.
Parotid= almost totally serous
Submandibular=mostly serous but some mucus
Sublingual=almost completely mucus
What separates the superficial and deep sections of the submandibular gland.and how are they linked together?
They’re separated by the mylohyoid muscle and the Wharton’s Duct links them together.
What is the secretin difference between the superficial and deep submandibular glands?
The outer superficial is mainly mucus acini
The inner deep is mainly serous acini
How are salivary glands stimulated?
The simulation is Nueral only,
Parasympathetic = produce a large volume of watery salami rich in enzymes _rest and digest
Sympathetic = produces a small, thick secretion of saliva rich I mucus_fighr or flight
Describe the parts and functions of the hepatic blood supply.
Hepatic portal vein - arterial blood goes to intestines to become nutrient and toxin rich, then travels to liver to deliver nutrients and toxins, then back to inferior vena cava. This blood is O2 poor.
Hepatic artery- O2 rich blood from aorta and spleen join in hepatic artery
What is the % of oxygenated and deoxygenated blood the liver receives?
25-30% oxygenated from hepatic artery
70-75% deoxygenated from portal vein
What does each liver lobule contiain?
A bile duct and canal A portal venule A hepatic arterial Hepatic sinusoids All linking to a central canal
What is a hepatic sinusoid?
An irregularly shaped tube through which deoxy nutrient rich blood travels to the central canal. Sinusoidal cells have large gaps between them called sinusoids to allow lots of exchange.
What is the function of each lobule’s central canal?
It joined all the other canals and blood supplies in the lobule back up to the hepatic vein ready to send to the heart.
Describe a continuous blood vessel and where it can be found in the body.
A tightly joined endothelial layer (many tight junctions) covered in an enclosed basement membrane. Used in the brain and most of the body.
Describe a Fenestrated blood vessel and where it can be found in the body
It’s endothelial layer contains many tiny holes to allow fast exchange across membrane. Has a continues basement layer acting as a slight barrier. Found in the pituitary, SI, kidney and some endocrine glands.
Describe a sinusoid blood vessel and where it can be found in the body.
Has intracellular gaps and gaps in the basement membrane. Allows large molecules and cells to get through. Newly made cells enter here ie rbc’s and hormones. Found in the spleen, bone marrow, liver and lymph nodes.
Describe the shape and design of a liver lobule.
Hexagonally shaped. Each of the 6 points contains a triad of blood vessels. The sinusoids are sigmoidal (travel in all directions not just laterally)
