Digestive System Flashcards
What does the salivary glands secrete?
Saliva
What is the function of the salivary glands?
Moisten and bind food particles, begins carbo digestion, & acts as a solvent to dissolve food chemicals (necessary to taste), & clean mouth and teeth
What are the 2 types of cells in salivary glands?
Mucous and serous
Which cell type secretes amylase?
Serous
What does amylase do?
Digestive enzyme that splits starch and glycogen into disaccharides
Which cell type secretes mucus?
Mucous
What does mucus do?
Thick, stringy liquid that binds food and acts as lubricant during swallowing
What are the 3 major glands in salivary glands?
Parotid, submandibular, sublingual glands
Which major gland is also known as submaxilary?
Submandibular
Which major gland is the smallest and found on floor of mouth under tongue and secretes a
thick & stringy fluid?
Sublingual glands
Which major gland is the largest and found in front of and below ear and secretes watery fluid
containing amylase?
Parotid
Which major gland is located on inside surface of jaw in floor of mouth and secretes a more
viscous fluid than the parotid glands?
Submandibular (submaxilary)
The pharynx connects what 2 cavities with what 2 things?
Connects nasal and oral cavity with larynx and esophagus
What are the 3 parts of the pharynx?
Nasopharynx, oropharynx, and laryngopharynx
Which part of the pharynx is located behind the nasal cavity?
Nasopharynx
Which part of the pharynx is located in the larynx?
Laryngopharynx
Which part of the pharynx is located in the oral cavity?
Oropharynx
How long is the esophagus?
25 cm
What is scattered throughout the esophagus to keep inner lining moist?
Mucous glands
What type of fibers are located in the esophagus?
Circular muscle
Where are these fibers found?
Within walls and thicken above esophagus/stomach juncture
Why do they contract?
To prevent regurgitation
When to they relax and why?
When peristaltic waves reach stomach to allow food to enter
What is the stomach shaped as?
J
What is the capacity of the stomach?
1 liter
The stomach is lined with thick folds called what?
Rugae
What is the function of the stomach?
Receive food, mix it with gastric juice, initiate digestion of proteins, absorb some
nutrients, and move food into small intestine
What are the 4 regions of the stomach?
Cardiac, fundic, body, pyloric
Which is a small area of the stomach near esophageal opening?
Cardiac
Which is the main part of the stomach?
Body
- Which are balloons above cardiac region and is temporary storage area of the stomach?
Fundic
Which part of the stomach narrows and becomes pyloric canal?
Pyloric
What is the thickening of muscular wall at end of canal?
Pyloric sphincter
What does the pyloric sphincter prevent?
Regurgitation from small intestine
What are the 3 gastric secretions and what do they secrete?
Mucous-mucus; chief-pepsinogen (inactive); parietal-HCl and intrinsic factor
What changes pepsinogen into pepsin?
HCl
What helps absorb vitamin B-12 from small intestine?
Intrinsic factor
What is viscous and alkaline to coat and protect inner stomach wall from pepsin digesting the
proteins of its wall?
Mucus
What is a protein-splitting enzyme?
Pepsin
What are 5 things the stomach can absorb?
Water, glucose, certain salts, alcohol, various lipid-soluble drugs
What is a semi-fluid paste of food and gastric juices and is pushed towards pyloric region?
Chyme
What rate depends on at which food empties to small intestine?
Fluidity of chyme and type of food
What is the order of substances that the stomach digests?
Carbos, proteins, fats
How long does it take to digest?
3-6 hrs
The pancreas serves as what 2 glands?
Endocrine and exocrine
Which gland releases hormones?
Endocrine
- Which gland secretes digestive juice?
Exocrine
The pancreas is an elongated, flattened organ that is posterior to what?
Stomach
What is the pancreas attached to and by what?
Duodenum of small intestine by a duct
What type of cells are in the pancreas?
Acinar
What do the acinar cells produce?
Pancreatic juice
What is the pancreatic juice capable of digesting?
Carbos, fats, proteins, and nucleic acids
What splits starch and glycogen into disaccharides?
Pancreatic amylase
What breaks triglycerides into 3 fatty acids and 1 glycerol?
Pancreatic lipase
What splits bonds of amino acids into proteins?
Proteinases
What are 3 kinds of proteinases?
Trypsin, chymotrypsin, and carboxypeptidase
The Trypsin, chymotrypsin, and carboxypeptidase are all secreted in their inactive form until they reach small intestine where other
enzymes do what?
Activate them
What breaks nucleic acid molecules into nucleotides?
Nucleases
What are two types of the nucleases?
DNA & RNA
Pancreatic secretions are regulated by what?
Parasympathetic nerve impulses and the hormones secretin and cholecystokinin
Parasympathetic nerve impulses and the hormones secretin and cholecystokinin
Parasympathetic nerve impulses and the hormones gastrin and cholecystokinin
Salivary secretions are regulated by what?
Parasympathetic nerve impulses
What is a mass of chewed food mixed with saliva rolled into a ball?
Bolus
What color is the liver and why?
Reddish/brown because well supplied with blood vessels
What is the largest gland in the body?
Liver
What are the 5 functions of the liver?
Metabolizes carbos, lipids, and proteins
Stores glycogen, vitamins A, D, & B12, and iron
Filters damaged RBCs and foreign substances from blood
Detoxificator – alters composition of toxic substances
Secretes bile
What color is the bile?
Yellowish green liquid
What is bile composed of?
Water, bile salts, bile pigments, cholesterol, and electroclytes
The liver is composed of how many lobes?
2
Which liver lobe is larger?
right
Each liver lobe is divided into what?
Tiny hepatic lobules
What does the tiny hepatic lobules contain?
Hepatic cells
What shape is the gallbladder?
Pear
How is it attached to surface of liver?
Cystic duct
What are the functions of the gall bladder?
Stores bile between meals
Concentrates bile
Releases bile into small intestine
How is the common bile duct formed?
By union of hepatic and cystic ducts
What does the hepatic and cystic ducts lead to?
Duodenum
What is the duodenum guarded by?
Sphincter muscle (sphincter of Oddi)
Presence of fat in small intestine triggers release of hormone cholecystokinin which stimulates
what?
Contraction of gall bladder
Bile salts are not a digestive enzyme, but aids in what?
The action of digestive enzymes
What is it when fat globules break into smaller droplets to mix with water, allowing lipases to
digest fat molecule better?
Emulsify
What do bile salts enhance absorption of?
Fatty acids, certain fat-soluble vitamins (A,D,E,K), and cholesterol
Lack of bile salts can cause what?
Vitamin deficiencies and lipids to be absorb poorly