Digestive system

examples of mechanical and chemical digestion

mechanical: chewing, churning in stomach

chemical: enzymes thats break down macromolecules

what is the function of the esophagus

moves food from mouth to stomach via peristasis

what is the function of the stomach

• recieves food from the esophagus

• chemically and mechanically digests

• has thick walls called rugae that allow it to expand

• has gastric glands

• has 3 muscle layers

what is the name for food that leaves the stomach

chyme

what are the 3 muscle layers of the stomach

longitudial, circular, oblique

how does chyme enter the small intestine?

via the pyloric sphincter

what is the function of the small intestine

• recieves chyme

• macromolecules are broken into nutrients which are then absorbed into blood capillaries and lacteals

• contains lymphoid tissues involved in immune response

what are the 3 parts of the small intestine

duodenum (upper), ileum (lower), jejunum (middle)

where is the bile duct that delivers bile from the liver and delivers pancreatic juice from the pnacreas

duodenum

what controls the digestive secretions

nervous system and hormones

what is a lacteal

a lacteal is a small lymphatic capillary in villi (walls of intestine are lined with villi)

what stimulates the gastric glands

gastrin produced by the stomach

what hormones does the duodenum wall produce

secretin and CCK

what do secretin and CCK do

stimulate the pancreas to secrete pancreatic juice and gallbladder to secrete bile

what does the large intestine do

• absorbs water, salts, and some vitamins

• stores indegestible material

• includes colon, cecum, rectum and anal canal

what is cecum

small pouch that forms the junction of small and large intestine

what does the colon include

ascending, transverse, descending, and sigmoid colon

how are feces forced into rectum

peristalis

what does the pancreas do?

Exocrine function: pancreatic cells produce pancreatic juice (to neutralize stomach acid) and digestive enzymes

Endocrine function: pancreas secretes insulin and glucagen (hormones that regulate blood sugar)

What are the 3 types of pancreatic lslets

Alpha cells = produce glycogen

Beta Cells = produce insulin

Delta = produces somatostatin

what does the liver do?

• largest gland

• contains 100k lobules that serve as structural and functional units

• detoxifies blood

• makes plasma proteins

• maintains blood glucose levels

• produces bile, contains bile salts that emulsify salt

• produce urea

• stores iron

What are the three structures of the liver

• bile duct

• hepatic artery branch

• hepatic portal vein

Galbladder ; what it do

• muscular sac attached to liver

• excess bile stores here

where does digestion begin

mouth

how are carbohydrates digested

• starts in mouth

• pancreatic amylase and maltase convert maltose in the small intestine to glucose

• glucose is absorbed by small intestine

How are proteins digested

• begins in stomache

• pepsin is produced by gastric glands that act on proteins

• trypsin and peptidases break down peptides into amino acids

how are fats digested

• lipase acts in the small intestine and digests molecules in the fat droplets after they have been emulsified

• glycerol and fatty acids enter the cells of the villi

Which enzyme is acidic

pepsin

which enzymes are produced in the pancreas

lipase, pancreatic amylase, trypsin, and nuclease

which enzymes are produced in the small intestine

maltase, peptidases, nucleosidases

which enzyme is produced in the gastric glands

pepsin

what enzyme is produced by salivary glanda

salivary amylase

which enzymes are produced in the pancreas, but are active in the small intestine

lipase, pancreatic amylase, trypsin, nuclease

which enzymes are produced and active in small intestine

nucleosidases, peptidases, maltase