Digestion and Nutrition
What are the three stages fir swallowing reflexes?
1. Food is mixed with saliva and voluntarily forced into the pharynx with the tongue. 2. Sensory receptors in the pharynx sense food, which triggers swallowing reflexes. 3. In the third stage of swallowing, peristalsis transports food in the esophagus to the stomach.
Gastric glands generally contain 3 types of secretory cells. What are they, and what do each of them do?
1. Mucous cells- produce mucous that protects the stomach lining 2. Chief cells- secrete pepsin (to digest protein) as inactive pepsinogen, which is activated when it comes into contact with Hydrochloric Acid. 3. Parietal cells- secrete Hydrochloric Acid
The digestive system consists of what two things?
1. alimentary canal, leading from mouth to anus 2. several accessory organs whose secretions aid the process of digestion
GASTRIC SECRETIONS REVIEW 1. Pepsinogen: where it's from and what it is 2.Pepsin: where it's from and what it is 3. Hydrochloric Acid: where it's from, and why it's needed 4. Mucus: where it's from and and it protects 5. Intrinsic Fiber: where it's from and what it's required for
1. from chief cells, inactive from of pepsin 2. from pepsinogen in presence of HCl, protein splitting enzyme 3. from parietal cells, needed to convert pepsinogen to pepsin 4. from goblet cells and mucous glands, protective to stomach wall 5. from parietal cells, required for B12 absorption
List and define the layers of the alimentary canal.
1. inner- MUCOSA is lined with epithelium attached to connective tissue; it protects tissues of the canal and carries on secretion and absorption 2. next layer- SUBMUCOSA made up of loose connective tissue housing blood and lymph vessels and nerves; it nourishes the surrounding layers of the canal 3. MUSCULAR LAYER consists of inner circular fibers and outer longitudinal fibers that propel food through the canal 4. outer- SEROSA composed of visceral pertinoneum that protects underlying tissues & secretes serous fluid to keep the canal from sticking to other tissues in the abdominal cavity
Peristaltic waves happen only ___ or ___ times during the day. What is the end result?
2, 3, bowel movement
The _____(#) primary teeth are shed in the order they appeared and are replaced by _____(#) secondary teeth.
20, 32
What is the pH of saliva?
6.5-7
What is the esophagus?
A straight, collapsible passageway leading to the stomach.
Cholecystokinin (__ __ __) is from where and stimulates the release of what with abundant __________ enzymes.
CCK, pancreatic juice, digestive
__________ of the intestinal wall stimulate parasympathetic reflexes that stimulate secretions for the small intestine.
Distension
___________ nutrients are those that _________ be synthesized by human cells.
Essential, cannot
_______________________ separate groups of hepatic cells.
Hepatic sinusoids
The stomach is a __-shaped, __________ organ that receives and mixes food with digestive juices, and propels food to the small intestine.
J-shaped, muscular
____________ are located at the root of the tongue.
Lingual tonsils
____________ & ___________ stimulation from chyme causes goblet cells to secrete _______.
Mechanical, chemical , mucus
______________ are scattered throughout the the submucosa of the esophagus and produce _________ to _________ and __________ the inner lining of the tube.
Mucous glands, mucous, moisten, lubricate
______________ is the process by which the body takes in and uses nutrients.
Nutrition
The _______ glands, lying in front of the ear are the largest of the major salivary glands; they secrete what?
Parotid, a clear, watery fluid rich in amylase
__________________(________) are on the posterior wall of the pharynx, above the border of the soft palate.
Pharyngeal tonsils (adenoids)
___________ movements include a wavelike motion called _________, which is caused by contraction behind a mass of food as relaxation allows the mass to enter the next segment of tube.
Propelling, peristalisis
Alimentary canal
a muscular tube about 8 meters long that passes through the body's ventral cavity
The small intestine is the major sight of ________ within the alimentary canal.
absorption
Amino acids are absorbed into the villi by ______ ________ and are carried away in the blood.
active transport
Monossaccharides are absorbed by the villi by ______ ________ or ________ _______ and enter blood capillaries
active transport, facilitated difusion
Two sets of teeth develop in sockets within the ____________ of the maxillary and mandibular bones.
alveolar processes
The anal canal opens to the outside of the _______; it is guarded by an ___________ internal anal sphincter and a __________ external anal sphincter muscle.
anus, involuntary, voluntary
The movements of the large intestine ______ similar to those of the small intestine.
are
The lips (are or aren't) highly mobile structures that surround the _______ opening.
are, mouth
The liver's role in digestion is to secrete the _____.
bile
Only the ____________ have a digestive function.
bile salts
Secretions from hepatic cells are collected in _____ canals that converge to become what and finally form the what?
bile, hepatic ducts, common hepatic duct
Bile salts emulsify (_______ _______) _____ and aid in the absorption of ______ acids, ________, and certain __________.
break down, fats, fatty, cholesterol, vitamins
Pancreatic juice contains enzymes that digest __________, ______, ________, and ________ _____.
carbohydrates, fats, proteins, and nucleic acids
The stomach is divided into ________, _________ ____, and _______ regions and a _______ ________.
cardiac, fundic body, pyloric, pyloric canal
The large intestine consists of ______ (pouch at the beginning of the large intestine), ______, the _______, and ___________.
cecum, colon, rectum, anal canal
Fatty acid molecules dissolve into the __________ of the villi.
cell membranes
Through the actions of ______, teeth break down food into smaller pieces, beginning _________ digestion.
chewing, mechanical
The soft palate and uvula function to do what?
close off the nasal cavity during swallowing
Each villus contains a core of _________________ housing blood capillaries and a lymphatic capillary called a _______.
connective tissue, lacteal
The hepatopancreatic sphincter remains ____________ unless a _______________ approaches it, at which time it _____ and a ______________________________________________________.
contracted, peristaltic wave, relaxes, squirt of bile enter the duodenum
Each tooth consists of a ______ & a _______, and is made of ______, ______, ______, _________, _____, and ____ _______.
crown and a root, enamel, dentin, pulp, cementum, nerves, blood vessels
It is connected to the ______ duct, which joins the ______ duct; these two ducts merge to form the ____________ duct leading to the duodenum.
cystic, hepatic, common bile
Defecation is stimulated by a __________ reflex that forces _______ into the rectum where what can happen to them?
defecation, feces, they can be expelled
Fatty acids are absorbed and transported _____________.
differently
The pancreas has an _________ function of producing pancreatic juice that aids _____________.
digestion
The ___________ system carries out the process of digestion.
digestive
The large intestine _______ digest or absorb nutrients, but it _____ secrete mucus.
doesn't, does
The small intestine is suspended from the posterior abdominal wall by a _____-layer fold of peritoneum called ________.
double mesentary
The small intestine consists of the __________, ____________, and ___________.
duodenum, jejunum, ileum
Secretin from the _________ stimulates the release of _________________ with a high bicarbonate ion concentration but few digestive enzymes.
duodenum, pancreatic juice
The ________________________ of the cells reconstruct the lipids.
endoplasmic reticulum
As chyme fills the duodenum, stretching of its wall triggers the ____________ reflex, which inhibits _____________ and slows the rate at which _______ enters the small intestine.
enterogastric, peristalsis, chyme
Presence of ____ and _________ in the upper small intestine cause the release of _______________ (__ __ __) from the intestinal wall, which also decreases gastric mobility.
fats, proteins, cholecytokinin (CCK)
The liver ______s the blood, removing damaged what & foreign substances, and removes what?
filters, red blood cells, toxins
The rate at which the stomach empties depends on the ________ of the chyme and the what?
fluidity, type of food
The papillae provide _________ for ______ food around the mouth.
friction, moving
Bile does not normally enter the duodenum until cholecystokinin (CCK) stimulates the __________ to do what?
gallbladder to contract.
As more food enters the small intestine, secretions of what from the stomach wall is reflexively inhibited?
gastric juices
Gastric glands within the mucosa of the stomach open as what?
gastric pits
The liver also stores _______, [vitamins __, __, __,] ________, and _______.
glycogen, A, D, B12, iron, blood
Cells that secrete mucus in the small intestine include _______ cells, which are abundant throughout the mucosa, and mucus-secreting glands located in the ___________ of the duodenum.
goblet, submucosa
Bile is a yellowish-_____, liquid that ______ cells secrete; it includes _______, ____ _______, ___________, and __________.
green, hepatic, water, bile pigments, cholesterol, electrolytes
Each lobe is separated into the ________________ consisting of _________ cells radiating from a central vein
hepatic lobules, hepatic
Blood from the ________________ vein carries blood rich in nutrients to the liver.
hepatic portal
The lips are ___________ and help to judge _________ and ________ of food.
highly senstitive, temperature, texture
Protein-digesting enzymes are released in an _________ from and are _________ upon reaching the ________________.
inactive, activated, small intestine
Different teeth are adapted the handle food in diferent ways, and include what?
incisors, supids, bicuspids, and molars
The inner wall of the small intestine is lined with _______________, which greatly increase the surface area available for absorption and aid in mixing actions.
intestinal villi
Other components of gastric juice include ___________________, required for vitamin _____ absorption in the _______________.
intrinsic fiber, B12, small intestine
Cheeks form the __________ of the mouth.
lateral walls
The liver is responsible fro many metabolic activities, such as _________ of __________, ______, and ________.
metabolism of carbohydrates, lipids, proteins
the motor functions of the alimentary canal are of two types:
mixing movements and propelling movements
Following a meal, _______ actions of the stomach turn the food into _____ and pass it toward the _____ region using peristaltic waves.
mixing, chyme, pyloric
__________ movements occur when smooth muscles contract ___________ in small sections of the tube.
mixing, rhymically
The salivary lands secrete saliva, which does what?
moistens food particles, binds them together, allows tasting, helps to cleanse the mouth & teeth, and begins carbohydrate digestion.
The large intestine absorbs electrolytes and water, secretes ________, houses _________________, forms ______, & carries out ____________ (________).
mucus, intestinal flora, feces, defecation (pooping)
Chylomicrons are carried away om ___________________ until they eventually join the bloodstream.
mymphatic lacteals
The Pharynx connects the ______ and ______ cavities with the larynx and esophagus and is divided into a ____________ (top part), ____________ (middle portion), and _______________ (bottom part).
nasal and oral nasopharynx, oropharynx, and laryngopharynx
The pharynx connects the ________ cavities with the ____________ and is divided into three stages.
nasal, esohpogus
The _______________________ systems regulate release of pancreatic juice.
nervous and endocrine
The ________ forms the roof of the oral cavity, or the what, and has an anterior hard _______ and a posterior soft ______.
palate, palate, palate
Associated with he palate in the back of the mouth _____________, which help to protect the body against what?
palatine tonsils, infections
The lengthy small intestine receives secretions from the _______ & ______, completes digestion of nutrients in chyme, absorbs the products of digestion, and ____________s the remaining residues to where?
pancreas, liver, transports, large intestine
The cells that produce pancreatic juice, called what, make up the ______ of the pancreas?
pancreatic acinar cells, bulk
Pancreatic enzymes include _______ ______, _________ ________, ________, ________, ______________, and ____ _______.
pancreatic amylase, pancreatic lipase, tryspin, chymotrypsin, carboxypeptidase, two nucleases.
Pancreatic acinar cells cluster around tiny tubules that merge to form larger ones, and then give rise to the _________________.
pancreatic duct
Gastric secretions are enhanced by _____________ impulses and the hormone _________, which is released from gastrin glands.
parasympathetic, gastrin
Salivary glands receive _______________ stimulation that triggers the production of a large volume of ________ at the _______ and _______ of food.
parasympathetic, saliva, sight, smell
The gallbladder is a _____-shaped sac lying on the __________ surface of the liver.
pear, inferior
Epithelial cells of the mucosa have embedded digestive enzymes on their micro villi including ____________(_________), _________ (________), ________ (________), and ________ (________) and intestinal ________ (_______).
peptidases (proteins), sucrase (sucrose), maltase (maltose), and lactase (luctose), and lipase (lipose).
Kupffer cells carry on ___________ in the liver
phagocytosis
These lipids collects in clusters that become encased in ________(________).
protein (chylomicrons)
The mouth is the first portion of the alimentary canal; it functions to do what?
receive food and begins mechanical digestion and mastication (chewing)
Bile pigments break down products from what cells?
red blood cells
Digestion
refers to the mechanical and chemical breakdown of foods so that nutrients can be absorbed by cells
The lower esophageal sphincter helps to prevent what?
regurgitation of the stomach contents into the esophagus
The liver is divided into _______________ lobes, and is enclosed by what?
right and left, fibrous capsules
The large intestinal wall has the _________ layers found in other ares of the alimentary canal, but lacks many of the features of the small intestinal mucosa.
same 4
The small intestine carries on ____________ & __________________ waves.
segmentation, peristaltic
The salivary glands contain _______ cells that produce a ________ fluid with _______, and ______ cells that produce _______ and ________ mucus.
serous, watery, amylase... mucous, lubricating and binding
A pyloric sphincter controls release of food from the stomach into the what?
small intestine
The pancreas is closely associated with the what?
small intestine
The pancreatic and bile ducts join and empty into the what, which is surrounded by the hepatopancreatic sphincter.
small intestine
The duodenum is the shortest and most fixed portion of the _________________; the rest is mobile and lies ____ in the ___________________ cavity
small intestine, free, peritoneal
The iliocecal sphincter is at the junction of the _________ and ______________ usually remains closed unless a gastroileac reflex is elicited after a meal.
small intestine, large intestine
A _____________ controls the release of bile from the __________________.
sphincter muscle, common bile duct
The _________ glands, inferior to the tongue, are the smallest of the major salivary glands and secrete what?
sublingual, a saliva that is thick and stringy
The _________ glands, located on the floor of the mouth, secrete what?
submandibular, a more viscous fluid
Fibers of the longitudinal muscle are arranged in _____ _______ that extend the entire length of the colon, creating a series of pouches, called _________.
teniae coli, haustra
The color of feces is due to what?
the action of bacteria on bile pigments
The odor of feces is due to what?
the actions of bacteria
The tongue is a ______, ________ organ covered by mucous membrane and housing taste buds with ________; it is attached to the floor of the mouth by the ________.
thick, muscular, papillae, frenulum
Between the bases of adjacent villi are ______________________________.
tubular intestinal glands
Feces are composed of ___________ material, _______, __________, ________, and ____________.
undigested, water, electrolytes, mucus, bacteria
The reddish-brown liver is located in the __________________ quadrant of the ___________ cavity, is the body's largest organ.
upper right, abdominal.
Intestinal glands are at the bases of the _______ secrete large amounts of watery ______ what carry digestive products into the villi.
villi, fluid
The intestinal villi also absorb _______ (by _______) and ___________ (by ________ ________).
water (osmosis), electrolytes (active transport)
The large intestine absorbs ________ and _________ and forms and stores _______.
water, electrolytes, feces
The stomach absorbs only small quantities of ________ and certain ______, _______, and some _______-_______ ______.
water, slats, alcohols, lipid-soluble drugs