-Connective tissue fills the spaces not occupied by epithelium, muscle, and nerve
Connective Tissue Functions
To bind and interconnect
e.g., ligaments, tendons
Support and nourishment
e.g., bone, omentum, adipose tissue
e.g., CT around blood vessels
e.g., bone, connective tissue of the skin, immune system
e.g., adipose tissue, extracellular matrix
Cells that carry out the main function of the tissue
e.g., Lung: airway and alveoli
e.g., Pancreas: exocrine and endocrine glands
Supporting Tissues / Cells or “STROMA”
Includes connective tissue cells
Includes connective tissue extracellular matrix
Within the pancreas, there are two types of glands --
Exocrine glands which secrete digestive products into a duct, which ultimately hooks up with other ducts and dumps into the intestine.
This exocrine gland is made up of epithelial cells (simple cuboidal) which are resting on an extracellular basement membrane.
The duct is composed of epithelial cells as well.
Since these glandular cells are conducting one of the functions of the pancreas, they can also be referred to as part of the “Parenchyma” of the pancreas (or “parenchymal cells”).
The left image shows a 2 dimensional section of an actual pancreas.
Note that the Basement membrane is extracelluloar “connective tissue” so technically is considered “stroma” (I.e., parts of the tissue which helps support the function of the glandular cells.
Connective tissue is everything not epithelial cell (muscle or nerve -- note: there is no muscle or nerve shown in these images).
So, connective tissue (aka stroma) includes all the white or light pink areas in the images.
Connective tissue (aka Stroma)also includes supporting blood vessels and blood (note, however, the the blood vessels themselves are lined by simple squamous epithelial cells called “Endothelial cells”).