Download Digestion Tube that transmits food through the body of an animal

Digestion
Tube that transmits food through the body of an animal from mouth
to anus.
alimentary canal
Enzyme produced by the salivary glands, the pancreas and the small
intestine. It converts starch to maltose during digestion. Its optimum
pH is slightly basic.
amylase
A small dead end tube arising from the caecum in humans.
appendix
A fluid secreted by the liver and stored in the gall bladder. Contains
pigments, cholesterol and organic salts. It aids digestion by:
 changing the pH of the stomach contents from acid to alkaline
 emulsifying fats to fat droplets
 activating pancreatic lipase.
bile
Tube that transports bile from the gall bladder to the duodenum.
bile duct
Quantity of moist food mixed with saliva, prepared in the mouth for
swallowing.
bolus
A sharp pointed tooth between the incisors and molars.
canine tooth
Ring of muscle found at the junction of the oesophagus and the
stomach. It allows entry of food into the stomach after it has been
cardiac sphincter
swallowed but prevents its return (usually).
Enzyme found in the tissues of plants and animals (e.g. celery and
liver). Breaks down hydrogen peroxide (H2O2), which is poisonous, to catalase
water and oxygen.
Fatty substance synthesised in the liver from certain animal fats.
High levels of this substance are associated with thickening of blood
cholesterol
vessels (arteriosclerosis) and may lead to a heart attack or stroke. It
is also involved in hardening of the arteries.
Contents of small intestine having been acted upon by pancreatic
enzymes and bile.
chyle
Contents of the stomach having been acted upon by the gastric
secretions.
chyme
The part of the large intestine from the caecum to the rectum.
colon
Difficulty in eliminating faeces. May be caused by a lack of fibre in
the diet.
constipation
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Removal of the amino group (-NH2) from an amino acid. This is done
to excess amino acids in the liver where the amino group is
converted to ammonia and then urea (which is excreted by the
kidneys).
deamination
The shape, number and arrangement of teeth of a species or
individual mammal. Varies with diet.
dentition
The physical and chemical process by which large particles and
molecules of food are broken down into simpler, soluble,
absorbable, usable forms.
digestion
The first portion of the small intestine immediately below the
stomach, approximately 30cm long.
duodenum
Elimination of faeces from the body, i.e. undigested or indigestible
and unwanted material. It is under the control of the anal sphincter
egestion
muscle. This is not excretion.
Food containing a large content of indigestible material (cellulose).
Provides bulk. Eating it makes you feel full and can prevent you
overeating as part of a balanced diet. It gives the muscles of the gut
wall something to push against. It keeps the contents of the gut
fibre
moving. It absorbs water, keeps faeces soft and easier to egest.
Prevents constipation. Helps prevent bowel (colon) cancer caused by
carcinogens produced by bacteria in the colon by absorbing and
diluting their effect.
A sac-like vessel that lies behind the lobes of the liver and stores
bile, which is produced by the liver. The bile duct drains it.
gall bladder
Collective term for all secretions by the glands in the stomach, e.g.
mucus, enzymes and hydrochloric acid.
gastric juice
The small intestine, where most digestion and absorption occurs.
ileum
Front tooth used for cutting food. Found between the canine teeth
(eye teeth) in upper and lower jaws.
incisor(s)
The process of taking food into the body through the mouth.
ingestion
Liquid produced by the intestines composed of mucus, enzymes and
other substances all of which have a role to play in digestion.
intestinal juice
An enzyme produced by the small intestine that converts lactose to
glucose and galactose during the process of digestion.
lactase
A lymph vessel in a villus of the small intestine. Absorbs fatty acids
and glycerol after digestion of fats.
lacteal
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An enzyme produced in the stomach, pancreas and small intestine,
which converts lipids to fatty acids and glycerol during the process of
lipase
digestion. Its optimum pH is slightly basic in the pancreas and small
intestine but acidic in the stomach.
Large exocrine gland and organ on right hand side of body below the
diaphragm and beside/over the stomach. Has a range of functions
which include:
· production of bile
· breaking down old red blood cells
liver
· detoxification of the blood
· storage of vitamins and minerals
· deamination of excess amino acids
· controlling the amount of glucose in the blood
· converts excess carbohydrates to fat
Enzyme produced by the small intestine that converts maltose to
glucose during the process of digestion.
maltase
A disaccharide reducing sugar, C12H22O11, formed from the hydrolysis
maltose
of starch.
One of the last three back teeth each side in the mouth, top and
bottom, including wisdom teeth, used for grinding food.
molar(s)
Tube that goes from the mouth to the stomach.
oesophagus
Large exocrine gland under the stomach that secretes enzymes
(trypsinogen, amylase and lipase), which enter the duodenum via a
duct. It is also an endocrine gland that secretes insulin.
An enzyme produced in the stomach when pepsinogen reacts with
the hydrochloric acid. It converts protein to polypeptides during the
process of digestion. Its optimum pH is acidic: pH = about 1 or 2.
Compound with two or more amino acids linked together in
sequence. A very small protein. Many of these form a poly.......
chain.
Method of moving substances, (e.g. food) through tubes (e.g.
intestines) by waves of rhythmic contractions and relaxations of
muscles.
pancreas
pepsin
peptide
peristalsis
That part of the digestive system that connects the mouth to the
oesophagus.
pharynx
Teeth located between the canines and first molars.
premolar
Enzyme produced by the salivary glands which converts starch to
maltose during the process of digestion.
ptyalin (salivary
amylase)
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Ring of muscle found at the junction of the stomach and small
intestine. It controls the rate of movement of chyme into the small
intestine.
pyloric sphincter
That part of the large intestine between the colon and the anus.
Stores faeces.
rectum
Enzyme produced in the stomach that converts soluble caseinogen
to insoluble casein during the process of digestion. Its optimum pH is rennin
acidic – pH = about 1 or 2.
Fluid produced and secreted by glands in the mouth; contains the
enzyme ptyalin or amylase.
That part of the alimentary canal between the jejunum and the
caecum. Most digestion and absorption occurs here. Inner walls not
smooth, thrown into folds. Folds covered by thousands of tiny
projections called villi. Villi increase surface area for release of
enzymes and absorption and transport of digested food.
A ring of muscle surrounding a tube or opening that closes when the
muscle is contracted. Controls the movement of substances through
it. e.g. cardiac and pyloric in the stomach and anal in the rectum, etc.
A sac-like structure found in the abdomen at the end of the
oesophagus and before the duodenum. Muscular walls help churn
food and the process of digestion is helped by the production of
gastric enzymes and hydrochloric acid.
An enzyme produced by the small intestine that converts proteins to
peptides during the process of digestion, its optimum pH is slightly
basic.
Small finger-like extensions/processes found in the small intestine
which increase the surface area for secretion and absorption.
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saliva
small intestine or
ileum
sphincter muscle
stomach
trypsin
villus / villi