BILLROTH’S OPERATION
junction, the hepatic duct becomes the
common bile duct, which opens into
the duodenum at a controlled orifice
known as the ampulla of Vater. The
presence of fat in the duodenum fol-
lowing a meal prompts the secretion
of a hormone that opens the ampulla of
Vater. This causes contraction of the
gallbladder, which squeezes stored bile
into the duodenum.
The main disorders affecting the bil-
iary system are
gallstones,
congenital
biliary atresia
and
bile duct obstruction.
(See also
gallbladder, disorders of.)
biliousness
A condition in which bile is brought up
to the mouth from the stomach. Bil-
iousness is also used as a nonmedical
term for nausea and vomiting.
bilirubin
The main pigment in
bile.
Bilirubin is
produced by the breakdown of
haemo-
globin,
the pigment in red blood cells.
Very high levels of bilirubin cause the
yellow pigmentation of
jaundice.
Prod-
ucts formed from the breakdown of
bilirubin make faeces brown.
Billings’ method
A technique (also known as the mucus
inspection method) in which a woman
notes changes in the characteristics of
mucus produced by her cervix. The
technique is employed to predict ovula-
tion for the purposes of
contraception
or
family planning.
Billroth’s operation
A type of partial
gastrectomy
in which
the lower part of the stomach is sur-
gically removed. Previously used in the
treatment of
peptic ulcers,
the operation
B
FUNCTION OF THE BILIARY SYSTEM
The biliary system consists of the bile ducts leading from the liver and gallbladder,
the gallbladder itself, and associated structures. The system drains waste products
from the liver into the duodenum and aids the process of fat digestion through
controlled release of fat-emulsifying agents (contained in bile).
FAT DIGESTION
L i v e r
B ile i s s e c r e t e d b y l i v e r c e l l s
a n d c o l l e c t e d in a s y s t e m o f
t u b e s ( d r a i n a g e c h a n n e l s ) .
B ile i s c a r r i e d o u t o f t h e liv e r
v ia t h e h e p a t i c d u c t s
C y s t ic d u c t
T h is c a r r i e s b i l e b e t w e e n
t h e g a l l b l a d d e r a n d t h e
c o m m o n b i l e d u c t .
G a l l b l a d d e r
______
B ile is c o n c e n t r a t e d
a n d s t o r e d h e r e a n d
i s r e l e a s e d b a c k in t o
t h e c o m m o n b i l e d u c t
w h e n t h is o r g a n
c o n t r a c t s .
D u o d e n u m
________
W h e n f a t f r o m a r e c e n t
m e a l a r r i v e s in t h e
d u o d e n u m , a h o r m o n e
i s r e l e a s e d t h a t a c t s o n
t h e g a l l b l a d d e r . T h e
g a l l b l a d d e r c o n t r a c t s ,
c a u s i n g b i l e t o b e
p a s s e d in t o t h e
d u o d e n u m t o e m u ls if y
t h e fa t .
C o m m o n b i l e d u c t
T h e h e p a t i c d u c t
b e c o m e s t h e c o m m o n
b i l e d u c t , w h ic h l e a d s
t o t h e in t e s t in e .
F o o d
A m p u l la o f V a t e r
B i l e e n t e r s t h e
d u o d e n u m h e r e .
I le u m
P a n c r e a s
In r e s p o n s e t o t h e p r e s e n c e o f f a t i n t h e d u o d e n u m , t h e
p a n c r e a s p r o d u c e s h o r m o n e s t h a t s t i m u l a t e c o n t r a c t i o n
o f t h e g a l l b l a d d e r a n d c a u s e t h e a m p u l l a o f V a t e r t o
o p e n s o t h a t b i l e f l o w s in t o t h e d u o d e n u m .
S t o m a c h
F a t a n d o t h e r p r o d u c t s o f
d i g e s t i o n p a s s f r o m t h e
s t o m a c h t o t h e d u o d e n u m .
1
Dietary fat passes from the stomach
to the duodenum in the form of large
droplets.
2
Bile released into the duodenum
contains salts that disperse the fat
into smaller droplets.
3
The fats are now more easily broken
down by lipase, an enzyme made by
the pancreas, and absorbed through the
intestinal lining.
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