Digestive System

Our mouth contains __ deciduous teeth and __ permanent teeth

28, 32

The alimentary canal is approximately __m or __ft long

9, 30

__________ is the passage of digested end products from the lumen of the GI tract through the mucosal cells by active or passive transport into the blood or lymph

Absorption

The _________ _________ takes in food, breaks it down into nutrient molecules, absorbs these molecules into the bloodstream, and then rides the body of indigestible remains.

Digestive System

_________ is taking food into the digestive tract (eating - only by the mouth)

Ingestion

___________ is partly voluntary and part reflexive

Mastication

_________ ________ increases the surface area of ingested food, physically preparing it for digestion by enzymes

Mechanical breakdown

_________, the major means of propulsion, involves alternating waves of contraction and relaxation of muscles in the organ walls

Peristalsis

________ moves food through the alimentary canal, includes swallowing, which is initiated voluntarily, and __________, an involuntary process

Propulsion, peristalsis

______ contains IgA antibodies, Iysozyme, defensins

Saliva

The GI tract _______ the digested fragments through it's lining into the blood

absorbs

In the esophagus, the series is replaced by an _________

adventitia

The _________ ______, also called the ___________ ______ or gut, is the continuous muscular tube that winds through the body from the mouth to the anus.

alimentary canal, gastrointestinal tract

__________ stops once food reaches the stomach

amylase

saliva contains the enzyme ________ that begins the digestion of starchy foods

amylase

The large intestine leads to the terminal opening, or ______.

anus

The ________ _______ - the branches of the celiac trunk that serve the spleen, liver, and stomach, and serve small and large intestines

arterial supply

Teeth are held in the _____ sockets

aveolar

The tongue mixes food with saliva, forming it into a compact mass called a _____

bolus

The ______ phase occurs in the mouth and is voluntary; food bolus leaves the mouth

buccal

The ______ or cuspids tear and pierce food

canines

The esophagus joins the stomach at the _____ _______ is surrounded by the ______________ or ______ sphincter

cardial orifice, gastroesophageal, cardiac

food is converted to a paste called _____

chyme

The two major regions f the tooth are the ____ and the _____

crown, root

________ eliminated indigestible substances from the body via the anus in the form of feces (done only by the large intestine)

defecation

_________ involves a series of catabolic steps in which enzymes secreted into the lumen of the alimentary canal break down complex food molecules

digestion

The GI tract ______ food - breaks it down into smaller fragments

digests

The GI tract has its own _____ ______ _______, which consists of over 100 million neurons

enteric nervous system

The ______ ________ ________ is the in-house nerve supply of the alimentary canal

enteric nervous sytem

The enteric nervous system is staffed by _____ _______ that regulate digestive system activity

enteric neurons

The upper ___________ sphincter is involved in the buccal and pharyngeal-esophageal phase

esophageal

The __________ contains a mucosa (stratified epithelium), submucosa (connective tissue), muscular external (circular and longitudinal layer), and adventitia (connective tissue)

esophagus

The __________ is a muscular tube and is collapsed when not involved in food propulsion

esophagus

eating too much meat can erode away the _________

esophagus

The ________ muscles of the tongue alter the tongue's position; prude, retract, move side to side

extrinsic

Most saliva is produced by the ________ ________ _______

extrinsic salivary glands

The _______ __________ roughen the tongue surface, helping us lick semisolid foods

filiform papillae

______ _______ are located on the lateral aspects of the posterior tongue

foliate papillae

The _________ ________ are scattered widely over the tongue surface

fungiform papillae

_______ is common in those with hiatal hernia; can also result in esophagitis and esophageal ulcers; esophageal cancer

heartburn

_________ is the first symptom of gastroesophageal reflex disease (GERD) and is the burning that occurs when stomach acid regurgitates into the esophagus (irrigation of cardiac sphincters)

heartburn

The _______ _____ __________ collects nutrient-rich versus blood draining from the digestive viscera and delivers it to the liver

hepatic portal circulation

the 6 activities of the digestive tract involve: _______, _________ ______, ________, _________, _________, _________

ingestion, mechanical breakdown, propulsion, digestion, absorption, defecation

The ______ ________ is the median fold that joins the internal aspect of each lip to the gum

labial frenulum

The _________ ________, which underlies the epithelium, is a loose areolar connective tissue. Its capillaries nourish the epithelium and absorb digested nutrients

lamina propria

The _______ _________ holds the tongue in place

lingual frenulum

the typical digestive mucosa consists of three sublayers: a ______ ________, a ______ ________, a _______ ________

lining epithelium, lamina propria, muscularis mucosae

salivary ______ breaks down lipids

lipase

_______ reflexes involve CNS integration centers and extrinsic autonomic nerves

long

Digestive activity is provoked by a range of ________ and ________ stimuli

mechanical, chemical

A ________ is a double layer of peritoneum - a sheet of two serous membranes fused back to back - that extends to the digestive organs from the body wall

mesentery

The _________ is also called the oral cavity

mouth

The organs of the alimentary canal are the ________, ________, ________, _______, ________ ________, _________ _________.

mouth, pharynx, esophagus, stomach, small intestine, large intestine

The innermost layer is the _______, or ______ ____________, a moist epithelial membrane that lines the alimentary canal lumen from mouth to anus

mucosa, mucous membrane

The four layers of the alimentary canal include: _______, ________, ________ ______, __________

mucosa, submucosa, muscularis externa, serosa

______ cells produce mucus, a stringy, viscous solution

mucus

Surrounding the submucosa is the __________ ________, also called the _________

muscularis externa, muscularis

External to the lamina propr. is the _________ __________, a scant layer of smooth muscle cells that produces local movements of the mucosa that enhance absorption

muscularis mucosae,

__________ and ___________ control digestive activity

neurons, hormones

bacteria that live on the back of the tongue promote the conversion of food-derived nitrates in saliva into _______ ______

nitric oxide

________ secretes and maintains the dentin

odontoblast

The ______ _______ boundaries are the lips anteriorly, cheeks laterally, palate superiorly, and tongue inferiorly

oral cavity

The area that lie within the teeth and gums is the _____ ______ ________

oral cavity proper

The oral cavity's anterior opening is the _____ _______

oral orifice

The recess bounded externally by the lips and cheeks and internally by the gums and teeth is the _____ ________

oral vestibule

Salivation is controlled primarily by the ____________ division of the autonomic nervous system

parasympathetic

The three salivary glands are the: ________ gland, _________ gland, ___________ gland

parotid, sublingual, submandibular

between the two peritoneums is the ________ _________, a slitlike potential space contain a slippery fluid secreted by the serous membranes

peritoneal cavity

digestive organs that keep their mesentery and remain in peritoneal cavity are __________ _________

peritoneal organs

The _________ of the abdominopelvic cavity is the most extensive serous membrane

peritoneum

_________ is the inflammation of the peritoneum

peritonitis

__________ is inflammation of the peritoneum. Can arise from an ulcer that leaks stomach juices into the peritoneal cavity.

peritonitis

Two sets of teeth; the primary or ________ dentitions and the _________ or milk or baby teeth

permanent, deciduous

the _________ - ________ phase is involuntary and is controlled by the swallowing center in the brain stem

pharyngeal-esophageal

The ________ or bicuspids and ______ are best suited for grinding or crushing

premolars, molars

organs that loose their mesentery which include the pancreas and duodenum and parts of the large intestine, are called __________ ______

retroperitoneal organs

The _____ allows the stomach to hold different portion meals

rugae

When we ingest food, chemoreceptors and mechanoreceptors in the mouth send signals to the _________ ______ in the brain stem to increase saliva output

salivatory nuclei

there are 5 tastes: _______, ________, ______, ______, _______

savory (umami), sweet, sour, salty, bitter

Mechanical processes include chewing, mixing food with saliva by the tongue, churning food in the stomach, and _________

segmentation

__________ misses food with digestive juices and makes absorption more efficient by repeatedly moving different parts of the food mass over the intestinal wall

segmentation

The ______, the outermost layer of the intraperitoneal organs.

serosa

______ cells produce a watery secretion containing enzymes, ions, and a tiny bit of mucin

serous

The salivary glands are composed of two types of secretory cells: _____ and _______

serous, mucous

________ reflexes are mediated entirely by enteric nervous system plexuses in response to stimuli within the GI tract

short

The lips and cheeks are composed of a core of ________ muscle

skeletal

Effectors of digestive activity are _______ muscle and _______

smooth, glands

The __________ _________ includes those arteries that branch off the abdominal aorta to serve the digestive organs.

splanchnic circulation

The _________ is a temporary "storage tank" where chemical breakdown of proteins begins

stomach

The _____ contains a friction-resistant _______ ________ _________

stratified squamous epithelium

The walls of the mouth are lined with thick _______ ________ ________

stratified squamous epithelium

The _________, just external to the mucosa, is areolar connective tissue containing a rich supply of blood and lymphatic vessels, lymphoid follicles, and nerve fibers which supply the tissues of GI tract

submucosa

The ___________ nerve plexus occupies the submucosa and the large ___________ nerve plexus lies between the circular and longitudinal muscle layers of the muscular externa

submucosal, myenteric

The pharynx and esophagus serve to ________ or deglutition

swallow

______ ____ give us the desire to eat food

taste buds

The accessory digestive organs are the _______, _______, ______, and a number of large digestive glands - the ______ _____, ______, _______

teeth, tongue, gallbladder, salivary glands, liver, pancreas

The ________ ______, distinguishes the oral cavity from the oropharynx (vallate papilla from lingual tonsil)

terminal sulcus

The ______ ________ are located in a V-shaped row at the back of the tongue

vallate papillae

The _______ __________ covers the external surfaces of most digestive organs and is continuous with the ___________ _______ that lines the body wall

visceral peritoneum, parietal peritoneum

Saliva is largely _______ - 97 to 99.5% and is therefore hypo-osmotic

water