Homeostasis ll

1.   The pancreas

- functions as exocrine + endocrine gland.

- has 2 groups of cell in the pancreas.

- α & β-cells in the islet of Langerhans play (major role in blood glucose concdntration).

- α-cells - secrete glucagons

- β-cells - secrete insulin into blood capillaries.


α & β-cells in the islet of Langerhans



2.   Blood glucose level rises↑à due to carbohydrate breakdown.

3.   Insulin + glucagons have opposite effects.

4.   Insulin:

-  secreted by β-cells (when glucose↑ level increases).

-  target organs = liver + muscle tissues.

-  convert glucose à to glycogen.

5.   Glucagon:

-  secreted by α-cells (when the glucose↓ level decreases)

-  Target organ = liver cells.

-  convert glycogen à glucose.


Pancreas response to different level of glucose



6.   Ingestion of glucose à increase insulin level ↑.

7.   2 types of diabetes: Type I & Type II.

Blood glucose & insulin level in normal & diabetic person.

8.   Formation of tissues fluid is a physical process.

9.   At arteriol end:  

-  smaller blood plasma content is forced out

-  when hydrostatic pressure (HP) > osmotic pressure (OP).

10. At venous end:

-  tissue fluid re-enters capillary

-  when osmotic pressure (OP) > hydrostatic pressure (HP).