Accessory Organs in Digestion

Pg 222 Sec 12.2

• Flat

• Elongated

• Located deep along back of abdomen

The Pancreas

Function:

I. Make pancreatic juices-i)Sodium bicarbonate( NaHCO3) : neutralizes chyme

ii) Enzymes:-pancreatic amylase (starch)-trypsin (proteins-lipase ( fats)

Juices travel to duodenum via duct from pancreas

Function:

II. Make hormones to regulate blood sugar

i) insulin

ii) glucagon

The insulin – glucagon relationship

i) INSULIN RESPONSE

1)You eat a meal2)Levels of glucose in blood rise3)Pancreas releases INSULIN4)CELLS take up sugar & LIVER forms glycogen

from excess glucose5)Blood sugars lower

ii) GLUCAGON RESPONSE

1)You have NOT eaten in a long time…2)Levels of glucose in blood DROP3)Pancreas releases GLUCAGON4)Liver breaks down glycogen to release

glucose 5)Blood sugar levels RISE

THE LIVER: `gatekeeper to the blood`

Liver

• Large, in top right of abdomen

• 2 main lobes

• *100,000 smaller `lobules` form structural units

• Blood vessels from villi in sm. intestine merge into HEPATIC PORTAL VEIN which leads to the liver

6 Functions of the LIVER

1. Detoxifies Blood - removes poisonous substances

- Also removes & stores iron, vitamins A,D,E, K

2. Helps Maintain Glucose Levels- homeostasis= 100mg glucose/100ml

-after eating stores glucose as glycogen-between meals breaks down glycogen to release glucose

3. Produces Bile -to break down (emulsify) fat

6 Functions of the Liver

4) Breaks down hemoglobin in Red Blood Cells -forms bilirubin -pigment in bile

5) Makes Urea -from broken down amino acids

6) Makes blood proteins -from amino acids

Gallbladder

• Small, Pear-shaped Sac• Below Liver

• FXN:• Stores & Releases bile • Bile travels via duct to duodenum• Bile emulsifies fat (breaks globs into small drops)

What Happens When the Parts Don’t Work…

Doctor can you please explain to me..1) Why is poop brown

2) What causes constipation

3) Are polyps on the colon a cause for concern

4) Why is Jaundice in babies a concern

5) What causes cirrhosis of the liver

6) How does diet relate to gall stones