Digestive [3] Flashcards
The pancreas’ exocrine function is to secrete _______ via a duct system leading to the ______. Enzymes are converted to their ____ forms once they reach the ____.
Precursors of digestive enzymes as an alkaline pancreatic juice
Duodenum
Active
Duodenum
Name the 3 things that secrete into the duodenum and what they secrete
Stomach - acidic chyme
Liver - bile
Pancreas - juices
The main pancreatic duct is called the ____ then there are smaller branches called ____ then twigs called ____ then leaves called _____.
Trunk
Interlobular ducts
Intercalated ducts
Acini
Name the 3 regions of the duodenum
Duodenum
Jejunum
Ileum
The duodenum is ____ shaped, _____ mesentery.
C
Not suspended by mesentery
Four layers of the gut tube are like usual in the small intestine except the mucosa is _____ and the submucosa just downstream of the _____ contains _____ which function as ___
Specialized to greatly increase surface area for secretion and absorption
Pyloric sphincter
Mucous glands (brunner’s)
Neutralizing chyme with HCO3- and optimizes pH ok for pancreatic enzymes
4 ways the small intestine increases surface area
Gross convolutions
Plicae
Villi
Microvilli
The plicae in the small intestine are ______ covered with _____ and has a core of _____.
Circular folds
Mucosa
Submucosa
The villi in the small intestine are on top of the ___ projecting into the lumen. Covering is ___, core is ____.
Plicae
Epithelium
Lamina propria
The lymphatic vessels in the SI transport ____. The capillaries transport ____. Venules in the ____ are from the ___
Absorbed lipids
Carbs proteins H2O electrolytes
Submucosa
Hpv
Paneth cells
Secrete bacterial lysozome, phagocytes
Found at the bottom of the folds
Enteroendocrine cells
Secrete secretin which tells the liver and pancreas that it needs juices and stuff. Secretes it into the capillaries I’d the Lamina propria
Secretin is stimulated by stomach chyme
Gastrin also secretes to tell glands to secrete enzymes
The surface cells of the small intestine are ___ and _____ cells. Their functions are:
Columnar absorptive
Goblet
The 2 parts of the mucosa of the SI are the
Villus
Intestinal gland
The SI mucosa is shed every _ days except _ cells
5
Paneth
The lymph vessels within each villus of the SI is called _____. Lymph is milked along the lacteal by ____. These Fibres arise from the ____
Lacteal
Smooth muscle in the Lamina propria
Muscularis mucosae
Main function of the large intestine:
Other 4 functions:
Water absorption
Converts chyme to feces, bacteria ferment remaining carbs
Bacteria produce some vitamins which are absorbed.
Secretion of mucus to lubricate feces
Defecation
Name the parts of the colon
Ascending, transverse, descending, sigmoid
Ileocecal valve controls __
Flow of chyme from ilium to caecum
What happens in the caecum
Bacteria digest. Humans can’t digest cellulose of plants
Faeces contain ____, undigested _____, cells _____ and ____. Faeces colour is from pigments derived from bacterial decomposition of ____
Bacteria Dietary fibre Cells shed Mucous Bilirubin
The four layers of the gut tube of the large intestine are as usual except the ___ and ___ are different
Mucosa
External muscle
What is different about the mucosa of the large intestine?
No villi but has intestinal glands Enterocytes Goblet cells, no paneth cells Replaced every 5 days Clusters of lymphoid nodules in the Lamina propria reflecting large bacterial content of colon
What is different about the external muscle of the large intestine
OL muscle thickened in 3 strips called teniae coli which contract to pull intestinal tube into pockets (haustra). Haustra change shape and position
Name the 4 types of cells in the large intestine
Columnar absorptive cells (enterocytes) absorb mostly water.
Goblet
Undifferentiated
WBC
The last bit of the anus is called the ___ which is closed by 2 sphincters:
Anal canal
Inner involuntary
Outer voluntary
You feel like u need to Pooh when you are at __% of ____. Stretching of this wall initiates ____. Shortening of the tube makes the ___ sphincter open
25
Rectum
Contraction of teniae coli
Internal
