CHAPTER 39- NUTRITION AND DIGESTION STUDY GUIDE
(filled in version)
calorie- energy needed to raise 1 gram of water 1ºC
Calorie = kilocalorie = food calorie (Adult needs ~ 1500 per day)
Nutrients (sources and function)
Water- the medium in which most cells live. Blood plasma is 90% water.
Minerals
Calcium- milk-bones and teeth
Chlorine- salt-fluid balance
Magnesium- milk, meat-muscle function, protein metabolism
Potassium- grains, fruits- nerve and muscle functions
Phosphorus-meats, grains, DNA, RNA, ATP
Sodium- salt- nerve and muscle function, water balance
Iron- liver, meat, raisins- Hemoglobin
Fluorine- water- bones and teeth
Iodine- seafood- salt- metabolic hormones
Carbohydrates-energy storage
Monosaccharides- one sugar (glucose, calactose, fructose)
Disaccharides- two sugar (sucrose, maltose)
Polysaccharides- (starch, cellulose)
Cellulose- indigestible—provides roughage in diet
Fats- energy, storage, protection, insulation
Saturated -vs- unsaturated (also check out this link
http://www.howstuffworks.com/fat2.htm
Saturated fats  deposit in arteries
2x energy potential of carbohydrates and proteins
By Tom McCurdy- New Monkey
Proteins-building blocks of tissue repair enzymes
Essential amino acids (8)
Vitamins
Fat-soluble vs water-soluble
http://www.mirakelle.com/wsva.htm
Fat Soluble: Vitamins A, D, E, and K are fat soluble because they can be stored in the
fatty tissues of they body. The body can build up small stores for future use.
Water Soluble: Vitamins C and B are water-soluble vitamins and cannot be stored.
Rickets \/ vitamin D- spindly bones, deformity
Scurry \/ vitamin c- bleeding gums, achy toothless
Vitamin k- Ecoli bacteria in intestine and blood clotting
Digestive tract organs and auxiliary organs
The digestive system includes
 The mouth
 Pharynx
 Esophagus
 Stomach
 Small intestine
 Large intestine
Major glands that add their secretions to the digestive system
 Salivary glands
 Pancreas
 Liver
Mechanical vs Chemical digestion
Great Link: http://www.borg.com/~lubehawk/hdigsys.htm
Mechanical is when the lips, cheeks, and tongue work in a carefully coordinated manner to place food
between the teeth for chewing… or basically when you chew your food. When you read "mechanical
digestion", think chewing, churning or grinding. These are physical processes that break food into smaller
pieces, but DO NOT change them chemically. The importance of mechanical digestion is that by breaking
food into smaller pieces it increases the surface area on which digestive enzymes can react during chemical
digestion.
Chemical digestion is straight forward: it involves chemicals (digestive enzymes) and the process of
hydrolysis. Large chemical nutrients are chemically converted to their smaller subunits
By Tom McCurdy- New Monkey
Mouth- teeth (types and functions)
Great Link: http://users.forthnet.gr/ath/abyss/dep1151.htm
composition of saliva
Slive Mucus
Digestive Enzymes
Antibacterial Enzymes
Salivary Amilase
“bolus” – Food and spit
By Tom McCurdy- New Monkey
Organ
Enzymes
Present
mouth
amylase (in
saliva)
esophagus
none
stomach
pepsin
gastric juice
hydrochloric
acid (HCl )*
small
intestine
What Happens Here
mechanical digestion of all food (teeth chewing &
grinding)
chemical digestion of carbohydrates begins
food passes from mouth through the esophagus to the
stomach
mechanical digestion of food (churning of stomach
walls)
chemical digestion of proteins begins
chemical digestion of carbohydrates, proteins, &
pancreatic juice
lipids continues & is completed
intestinal juice
the small, soluble nutrients (sugars, amino acids, fatty
bile*
acids) are absorbed
large
intestine
none
water is absorbed from unusable, indigestible wastes
(feces)
rectum
none
feces are temporarily stored
anus
none
feces are eliminated (egested) from the body
Esophagus
Structure – 25 cm long/10 inches
Circular muscles contract to pass bolus to stomach
Peristalsis
Stomach
Muscle Sac with 3 movement planes, Diagonal, Lengthwise and crosswise
Cardiac and pyloric sphincters
Secretions-mucus, HCI, pepsin
Mucus – Lube and protection
HCl – Breaks down food; PH is 0.6
Pepsin – Enzyme which breaks peptide bonds in proteins
Muscles churn food- mix food with gastric juices  Chyme watery acidic
After 2-6 hr Chyme is relased by pyloric valbe into small intstine
Factors of digestion:
1. meal size
2. fat content
3. emotions
Food Entering Stomach
Proteins (lg polypeptides
Disaccharides
Fats
“bolus”
Food Leaving Stomach
Small polypeptides
Disaccharides
Fats
“chyme”
By Tom McCurdy- New Monkey
Small Intestine- Chyme enters at duodenum with enzymes + digestive
Duodenal digestive juices – enzymes
Peptides
Maltose, lactose, sucrose
^
^
^
Glucose Glucose Fructose
Galactose glucose
Pancreatic digestive juices – trypsins, lipase, bicarbonate
Large Intestine- (colon) reabsorbs excess water
Fecal material moved by peristalsis to the rectum where it is expelled through the anus (mostly under
voluntary control)
Coliform bacteria (ecoli) make vitamin K
By Tom McCurdy- New Monkey