Nutrition&Diet - 2 [Alimentary Canal] Flashcards
Components of Gastroinstetinal tract
Alimentary canal
Small intestine
Large intestine
Accessory organs
Basic types of action on food
Mechanical - chewing, peristalsis
Chemical - salivary enzymes, digestive juices
What’re the valves/sphincter muscles are designed to
Retain food
Prevent “backing up”
A taste bud consists of….embedded in the surrounding epithelium, termed…
30-100 cells - replace themselves 3-10d
Papillae - most numerous on dorsal epithelium
How does the brain interpret flavours
By the nerve cells, they carry messages
What’s anosmia
Loss of smell
Persistent, abnormal distortion of taste
Dysgeusia
Dry mouth
Xerostomia
Adverse condition resulting form medical tx
Iatrogenic
Loss of taste
Hypogeusia
Heightened taste acuity
Hypergeusia
Loss/lack of appetite resulting in inability to eat
Anorexia
What’s phantom taste
Dysgeusia w/o identifiable taste stimuli
Functions of saliva
Lubricates - mucin
Antibacterial
Removes debris/microorg.
Neutralizes/dilute/buffers bacterial acid
Remineralize tooth
Prevents plaque accumulation
Facilitates taste
Ease of speech
Digestive functions of saliva
Mucin - glycoprotein- lubricates
Phyalin (amylase)- enzyme- hydrolysis
Lysozyme(antibody)-enzyme-breaks down cell walls of bacteria
What increases susceptibility to resorption and bone loss in the alveolar process
Ca balance is -
Which group of circular muscles fibres is located just above the stomach
LES
It also prevents regurgitation
What’s the product of the bolus mixed with gastric secretions
Chyme
What’re the major enzymes found in gastric juice
Pepsin
Lipase
Why does a low pH of stomach contents is beneficial
Kills/inhibits growth food bacteria
Denatures protein
Facilities hydrolysis
Active gastric enzymes
Major enzymes found in gastric juices
Pepsin
Lipase
Where does most vit and minerals are hydrolyzed and absorbed
Small intestine
Factors affecting digestion in the small intestine
Villi
Microvilli
Bile
Pancreatic enzymes
Which mechanism are used for absorption of nutrients
Passive diffusion
Active transport
Osmosis
Which portal is used for the absorption of nutrients from the GI tract and spleen into bloodstream to the liver
Portal vein
How much of ingested food and digestions secretions continue to the large intestine
5%
Functions of the large intestine
Reabsord water/electrolytes
Form/store residues until defecation
Why does a healthy micro flora is important
Break down substances human enzymes can’t digest
Synthesized vit
Boost immune system
Inhibit pathogenic bacteria
Difference between pro and prebiotics
Pro- produce specific host benefits through different mechanisms
Pre- non digestible food ingredients, provide fuel
Define constipation
Bowel movements <3/week w/hard/dry/small and difficult to pass stool
