Term
| describe what happens in the structure of the mouth when swallowing and why |
|
Definition
| muscles draw the soft palate and uvula upward to close to opening between the nasal cavity and the pharynx, thus preventing entry of food into the nasal cavity |
|
|
Term
| The four types of teeth and function |
|
Definition
Incisors
Canines
Premolars (bicuspids)
Molars (tricuspids) |
|
|
Term
| The three pairs of salivary glands |
|
Definition
parotid
sublingual
submandibular |
|
|
Term
| Describe the process of mastication |
|
Definition
1) teeth- cut, mash, tear, shred food
2) mandibular muscle movement and bones
3) mixing with saliva and enzymes to food and turn to bolus |
|
|
Term
|
Definition
| mostly water with mucus, also Na, bicarbonate, Cl, and K |
|
|
Term
|
Definition
| 7.4. The bicarbonate concntratin make saliva alkaline. |
|
|
Term
|
Definition
Turn broken down food into bolus
Neutralises bactericidal effects
Antimicrobial substance prevent infection
Keep mouth moist
|
|
|
Term
| Where is exogenous fluoride secreted and what is its function? |
|
Definition
Secreted by salivary glands
Function is to protect teeth from decay |
|
|
Term
| Why is it important that the mouth s moist (2) |
|
Definition
| Facillate speech and alow swallowing |
|
|
Term
| Which part of the brain controls vital body functionings (eg. respiratory rate, pulse)? |
|
Definition
| Medulla oblongata of the brainstem |
|
|
Term
| Which type of nervous system controls gastric functioning |
|
Definition
| Autonomic, parasympathtic nervous system |
|
|
Term
| Which body parts does the autonomic nervous system innervate |
|
Definition
| smooth muscles, internal organs, blood vessels and other parts of the body that is not controlled by concious thought |
|
|
Term
| Which parts of the nervous system does the peripheral nervous system innervate |
|
Definition
|
|
Term
| main organ control to increase salivary function |
|
Definition
| parasympathetic nervous system |
|
|
Term
| Three types of signals contributing to action potential (input) to increase saliva |
|
Definition
chemoreceptors- sense taste in mouth
mechanoreceptors- sense pressure and touch in mouth
cerebral cortex- thought, smell or sight of food |
|
|
Term
| another term for swallowing |
|
Definition
|
|
Term
| Three stages of deglutition |
|
Definition
1) oral
2) pharangeal
3) oesophageal |
|
|
Term
| 2 types of motility in digestive system |
|
Definition
| peristalsis and segmentation |
|
|
Term
| describe how muscles work to propel food in peristalsis |
|
Definition
circular muscles contract immediatly after food
circular muscles ahead of food relaxes to allow a wider diameter to travel through
longitudinal muscles contract as food enters the region, which decreases length food has to travel through and propelling food forward |
|
|
Term
| Why does thee food move back and forth during segmentation (2) |
|
Definition
| to adequatly allow for the mixing of digestive secretions and assist with mechanical digestion |
|
|
Term
|
Definition
| Posterior to mouth and nose. Leads to oesophagus |
|
|
Term
|
Definition
| nasopharynx, oropharnyx and laryngopharnyx |
|
|
Term
|
Definition
stores food
secretes digestive juices (turn bolus to chyme)
propels partially digestive food
|
|
|
Term
| passage which food passes into stomach from oesophugus |
|
Definition
| lower oesophageal sphinter |
|
|
Term
| Structures of stomach that relax to propel food into the duodenum of the small intestines |
|
Definition
| lesser and greater curvatures and pyloric sphinter |
|
|
Term
| Three muscularis layers of stomach |
|
Definition
| longitudinal, circular and obique |
|
|
Term
| Three factors influencing gastric emptying |
|
Definition
| volume, osmotic pressure and chemical composition of gastric contents |
|
|
Term
gastrin and cholecystokinin
|
|
Definition
two polypeptide hormones that are secreted by the gastrointestinal mucosa to facillitate relaxation of fundus when swallowing occurs |
|
|
Term
|
Definition
| gastrin (intestinal hormone) and nervous parasympathetic system |
|
|
Term
|
Definition
| sympathetic nervous system and secretin |
|
|
Term
| How is rate of peristalsis mediated |
|
Definition
| by pacemaker cells that initiate a wave of depolarisation. This moves from the upper part of stomach to pylorus |
|
|
Term
| part of stomach where mixing occurs |
|
Definition
| as food is propelled to the antrum of stomach by peristalsis |
|
|
Term
|
Definition
| when food approaches towards the pylorus of stomach, the peristaltic wave velocity increases the velocity and forces the contents of the food back into the stomach |
|
|
Term
| what are the reasons for retropulsion (2) |
|
Definition
| Effectively mix food with digestive juices and break down large food particles |
|
|
Term
| How long does food remain in stomach |
|
Definition
| 4 hours, add 2 for fatty meals |
|
|
Term
| why is cholecystokinin needed to slow gastric motility and decrease gastric emptying in stomach |
|
Definition
| so that fats are not being emptied into the duodenum at a rate exceeding the production of bile (from liver) and enzyme (from pancreas) secretion needed to break down fats |
|
|
Term
| where is HCl produced in stomach |
|
Definition
| parietal cells of gastric glands |
|
|
Term
| function of pepsin is stomach |
|
Definition
| break down protein into amino acids |
|
|
Term
|
Definition
| Cover mucosal folds of small intestines |
|
|
Term
|
Definition
secrete enzyme to break down food and
absorbs nutrients, electrolytes, vitamins, amino acids, fatty acids, water and simple sugare |
|
|
Term
| Areas where chyme can come from and empty into the duodenum |
|
Definition
| stomach and accessary organs: liver, gallbladder and pancreas |
|
|
Term
| ileogastric reflex function |
|
Definition
| inhibits gastric motility when ilieum becomes distended. Prevents continued movement of chyme into an already full ilieum |
|
|
Term
| intestinointestinal reflex |
|
Definition
| inhibits intestinal motility when one part of small intestines is overdistended. |
|
|
Term
| control and function of gastroileal reflex |
|
Definition
activated by increase in gastric motility and secretion
function is to stimulate an increase in ileal motility and relaxation of ileocaecal sphinter. This empties the ilieum and prepare it to recieve more chyme |
|
|
Term
| reflexes inhibitng gastric motility |
|
Definition
| ileogastric and intestinointestinal reflexes |
|
|
Term
| percentage of water reabsorbed in small intestines |
|
Definition
|
|
Term
| percentage of water reabsorbed in large intestines |
|
Definition
|
|
Term
| absorption percentange of organs for alchol |
|
Definition
20% stomach
80% small intestines |
|
|
Term
| What is absorbed in the large intestines |
|
Definition
| Na, K, H2O, acids and bases |
|
|
Term
| five +four componants of large intestine in order |
|
Definition
caecum
appendix
colon- ascending, transversing, descending & sigmoid
rectum
anus |
|
|
Term
| When is the defacation reflex stimulated |
|
Definition
| feces movement into the sigmoid colon |
|
|
Term
| What happens when defecation reflex is stimulated |
|
Definition
Rectal wall stretches and constricted internal relaxes
= urge to defecate |
|
|
Term
|
Definition
| autoimmune disease. Inflammatory response attacks own cells in digestive tract |
|
|
Term
|
Definition
| formation of divercula (pouches) in colon |
|
|
Term
|
Definition
| divercula become inflamed |
|
|
Term
|
Definition
| made up of two conditions- diverticulitis and diverticulosis |
|
|
Term
|
Definition
| inflammation of liver caused by virus |
|
|
Term
| mode of transmission: hepatitis A |
|
Definition
| primarily through food or water contaminated be faeces from an infected person, May spread by blood (rare) |
|
|
Term
| mode of transmission: hepatitis B |
|
Definition
| Contact with infected blood, sex, mother to child during childbirth (vaginal or cesarean) |
|
|
Term
| mode of transmission: hepatitis C |
|
Definition
| Contact with infected blood, less commonly by childbirth or sexual contact |
|
|
Term
| mode of transmission: hepatitis D |
|
Definition
| Infected blood, only occurs with hepatitis B infection |
|
|
Term
| mode of transmission: hepatitis E |
|
Definition
| through food or water contaminated from an nfected person |
|
|
