NFSC 125, Human Nutrition
Study Guide/Class notes
Exam#2
Spring 2004
Digestion and absorption
I. Overview of digestion + absorption
-What is digestion?
II. Mouth
-Describe the digestive processes taking place in the mouth?; what is saliva composed of?; what are the major electrolytes secreted?; Salivary glands: parotid, submaxillary + sublingual glands: cell types: serous, mucous cells – what do they secrete?; What is the function of mucus?
III. Esophagus
-Esophagus: describe the 3 stages of swallowing; what is the function of the esophagus?
what is primary versus secondary peristalsis?; cardiac sphincter
IV. Stomach
-Stomach: List the functions of the stomach; Gross anatomy; gastric gland:cell types-chief, parietal, mucus, endocrine- what do each secrete?; list types of gastric glands – what are the primary secretions of each?; 3 phases of gastric secretions and what happens in each?; Describe roles of acetylcholine/gastrin/histamine in HCL secretion; what 3 factors contribute to ulcer formation?; mechanical aspects of stomach, what is chyme?
V. Small intestine
-Small intestine: what's its primary function?; Gross Anatomy: list parts of small intestine: mesentery, serosa, muscles, submucosa, mucosa (villi); Describe its microanatomy- villus, crypt, enterocyte, microvilli, capillaries; describe the layers which impede absorption:
unstirred water layer, glycoprotein coat, lipid bilayer of cell membrane
VI. Absorption
-Absorption: define it.; List 4 factors that affect amount of nutrient absorbed; What are the two general ways that nutrients get across the intestinal cell? what are the differences between passive diffusion, facilitated diffusion, + active transport
VII. Pancreas
-Describe anatomy (describe the flow of compounds); exocrine vs endocrine function + name the secretions of each
VIII. The Liver/gall bladder
-what are their functions?; describe gross anatomy; What is bile? what is it composed of? what is it needed for?
IX. The Large Intestine
-Gross anatomy; what is its function?; what are feces?
X. The Circulatory system
-describe the general flow of water- and fat-soluble nutrients.
NFSC 125, Human Nutrition
Study Guide/Class notes
Exam#2
Spring 2004
Carbohydrate digestion and absorption
I. Be able to thoroughly discuss the digestion and absorption of carbohydrates.
(terms:salivary amylase; pancreatic amylase; gastrin; secretin; CCK; maltase, glucoamylase;
isomaltase or -dextrinase; sucrase; lactase; maltose, maltotriose, dextrins, sucrose, lactose,
duodenal papilla)
II. Be able to describe how glucose, fructose, and galactose are absorbed.
NFSC 125, Human Nutrition
Study guide/class notes
Spring 2004
Exam#2
Lipids
I. Overview
-List the general functions of lipids
II. Classification
-The Triglyceride
-draw the general structure of a fatty acid
-what's the difference between saturated, monounsaturated, + polyunsaturated fatty acids? (know how to recognize and draw structures based on nomenclature
(e.g., 18:1 (9)) and omega 3,6,9 fatty acids
-name the two essential fatty acids, why are they essential?, what happens in a deficiency?, what important products are formed from each? -trans versus cis fatty acid - what is a trans FA?, what are major food sources of trans FA? Possible health implications
-draw the general structure of a triglyceride
-Cholesterol:structure and importance; Function/Important products formed
-Food sources of cholesterol
-The phospholipid
-Draw the general structue of a phospholipid; importance of PLs, functions
-Glycolipid
III. Trends in consumption
-Describe the general trends in fat consumption: As a percent of total kcals; types of fat in the diet; cholesterol
-Be familiar with types of foods rich in saturated, mono + polyunsaturated fats + cholesterol
-what are the dietary recommendations for fat consumption?
Dietary Recommendations for fat:
DRI: AI: linoleic acid (omega 6) = 12-17 g/day
linolenic acid (omega 3) = 1.1-1.6 g/day
20 – 35% of total calories
Dietary guidelines/food label:
< 30% of total calories for fat
<10% of total calories from saturated fat
< 300 mg/day cholesterol
Food Guide Pyramid:
2-3 servings of dairy
2-3 servings of meat, poutry, fish, dry beans, eggs, and nuts
use fats, oils sparingly
NFSC 125, Human Nutrition
Study guide/class notes
Spring 2004
Exam#2
Lipid digestion and absorption
I. Be able to thoroughly discuss the digestion and absorption of dietary fat
(terms: lingual lipase, gastric lipase, CCK, secretin, bile, co-lipase, pancreatic lipase, phospholipase, MG, fatty acids, lysophospholipid, cholesterol esterase, retinol esterase, micelle)
-what happens to the digestive products of fat once they are absorbed into the intestinal cell? What's a chylomicron? How does it get to the general circulation? Be able to describe the metabolism of a chylomicron after it enters the general circulation.
NFSC 125, Human Nutrition
Study guide/Class notes
Spring 2004
Exam#2
Protein
I. Overview
-List some important products and functions of protein
II. Structure
-The amino acid - draw out the basic structure; what is meant by amphoteric?
-how are amino acids classified?, list names of essential amino acids
-The peptide bond - be able to draw out
-Describe the primary, secondary, tertiary and quaternary structures of proteins
III. Specific functions of AAs
-what are the specific functions of methionine, tryptophan, and phenylalanine/tyrosine?
IV. Protein Requirement
-Describe what is meant by protein turnover, what are the sources of protein intake and protein losses?
-why do we need to eat protein?
-define N balance: balance, positive balance, negative balance and give examples of each
-Be able to describe how protein RDA was determined using the N balance method + be able to calculate protein RDA
V. Protein quality
-Chemical score, Biologic value, Net protein utilization, PER; Be prepared to solve problems
VI. Vegetarian Diets
-common limiting amino acids in grains/legumes
-what is an incomplete protein?, what is meant by combining proteins?
-nutritional pros + cons
VII. Lack and excess of protein
-What are health consequences of lack of and excess of protein in the diet?
-chronic vrs acute protein malnutrition