Comprehensive Nutrition Final Exam Study Guide

Study Guide - Smart Notes

Tailored notes based on your materials, expanded with key definitions, examples, and context.

Anatomy & Physiology

Digestive System Segments and Accessory Organs

The digestive system is composed of several segments and accessory organs, each with specific functions in the breakdown and absorption of nutrients.

GI Tract Segments: Includes the mouth, esophagus, stomach, small intestine, and large intestine. Each segment has a unique role in digestion and nutrient absorption.
Accessory Organs: The liver, pancreas, and gallbladder assist in digestion by secreting enzymes and bile.
Digestive Enzymes: Enzymes such as amylase, lipase, and protease are secreted by various organs to catalyze the breakdown of carbohydrates, fats, and proteins.
Function: Each organ and enzyme contributes to the efficient processing of food into absorbable nutrients.

Example: The pancreas secretes insulin and digestive enzymes; the liver produces bile for fat emulsification.

Carbohydrates

General Properties and Types

Carbohydrates are organic compounds that serve as a primary energy source. They are classified based on their structure and function.

General Formula: Most carbohydrates follow the formula .
Caloric Content: 4 kcal/g.
Types: Monosaccharides (glucose, galactose, fructose), disaccharides (sucrose, lactose, maltose), and polysaccharides (starch, glycogen, cellulose).
Functions: Provide energy, store energy (glycogen), and support digestive health (fiber).

Example: Starch is a polysaccharide found in plants; glycogen is the storage form in animals.

Digestion and Metabolism

Enzymes: Amylase breaks down starches; sucrase, lactase, and maltase act on disaccharides.
Blood Glucose Regulation: Insulin lowers blood glucose; glucagon raises it.
Fiber: Soluble fiber lowers cholesterol; insoluble fiber aids bowel movement.
Diabetes: Type 1 is insulin-dependent; Type 2 is often related to insulin resistance.

Example: After a meal, insulin is released to help cells absorb glucose.

Lipids

Types and Properties

Lipids are a diverse group of hydrophobic molecules, including fats, oils, and cholesterol. They are essential for energy storage, cell membrane structure, and hormone production.

General Formula: Triglycerides consist of glycerol and three fatty acids.
Saturated vs. Unsaturated: Saturated fats have no double bonds; unsaturated fats have one or more.
Cis vs. Trans: Cis fats have hydrogen atoms on the same side of the double bond; trans fats have them on opposite sides.
Caloric Content: 9 kcal/g.

Example: Olive oil is rich in monounsaturated fats; butter contains saturated fats.

Lipoproteins and Cholesterol

Lipoproteins: Chylomicrons, VLDL, LDL, HDL transport lipids in the blood.
HDL: Known as "good cholesterol"; helps remove cholesterol from arteries.
LDL: Known as "bad cholesterol"; can deposit cholesterol in artery walls.

Example: High HDL levels are associated with reduced risk of heart disease.

Proteins

Structure and Function

Proteins are polymers of amino acids and are vital for growth, repair, and metabolic processes.

Amino Acid Structure: Central carbon, amino group, carboxyl group, and side chain (R group).
Essential Amino Acids: Cannot be synthesized by the body; must be obtained from diet.
Protein Digestion: Begins in the stomach (pepsin) and continues in the small intestine (trypsin, chymotrypsin).
Functions: Enzymes, hormones, structural components, immune response.

Example: Hemoglobin is a protein that transports oxygen in the blood.

Metabolism

Energy Production and Pathways

Metabolism encompasses all chemical reactions in the body, including energy production from macronutrients.

ATP: The primary energy currency of the cell.
Glycolysis: The breakdown of glucose to pyruvate, yielding ATP.
Catabolic vs. Anabolic: Catabolic reactions break down molecules; anabolic reactions build them.
Krebs Cycle: Central metabolic pathway for energy production.

Example: During exercise, muscles use ATP generated from glucose and fatty acids.

Micronutrients: Vitamins and Minerals

Water-Soluble Vitamins

Water-soluble vitamins include the B-complex group and vitamin C. They are not stored in large amounts and must be consumed regularly.

Functions: Coenzymes in metabolism, antioxidant activity.
Deficiency Symptoms: Vary by vitamin; e.g., vitamin C deficiency causes scurvy.

Example: Thiamin is essential for carbohydrate metabolism.

Fat-Soluble Vitamins

Types: Vitamins A, D, E, K.
Functions: Vision, bone health, antioxidant protection, blood clotting.
Deficiency Symptoms: Night blindness (vitamin A), rickets (vitamin D).

Example: Vitamin D is synthesized in the skin upon sunlight exposure.

Minerals

Major Minerals: Calcium, phosphorus, potassium, sodium, magnesium.
Trace Minerals: Iron, zinc, iodine, selenium.
Functions: Bone structure, fluid balance, nerve transmission.

Example: Iron is required for hemoglobin synthesis.

Water

Functions and Requirements

Water is essential for life, serving as a solvent, transport medium, and temperature regulator.

Survival: Humans can survive only a few days without water.
Distribution: Water is distributed throughout cells, blood, and tissues.
Functions: Maintains blood volume, removes waste, regulates temperature.

Example: Dehydration impairs physical and cognitive performance.

Energy Balance

Components and Calculations

Energy balance is the relationship between energy intake and expenditure, crucial for weight management.

Components: Basal Metabolic Rate (BMR), Thermic Effect of Food (TEF), Thermic Effect of Exercise (TEE).
Energy Equation:
Weight Management: Positive balance leads to weight gain; negative balance leads to weight loss.

Example: Calculating total daily energy expenditure helps set dietary goals.

Exercise and Fitness

Nutrition and Performance

Proper nutrition supports exercise performance and recovery.

Maximal Heart Rate: Estimated by .
Carbohydrate Loading: Increases muscle glycogen stores for endurance events.
Fluid Needs: Hydration is critical during and after exercise.

Example: Athletes may consume sports drinks to replenish electrolytes.

Life Cycle Nutrition: Pregnancy and Infancy

Pregnancy Nutrition

Nutritional needs increase during pregnancy to support fetal growth and maternal health.

Stages: Zygote, embryo, fetus.
Colostrum: The first milk produced, rich in antibodies.
Medical Conditions: Gestational diabetes, preeclampsia.
Weight Gain: Recommended weight gain varies by trimester.
Infant Feeding: Babies should not consume honey (risk of botulism) or cow's milk (risk of allergies and nutrient imbalance).
Transition to Solid Foods: Typically begins around 6 months of age.

Example: Iron-fortified cereals are often the first solid foods introduced to infants.

HTML Table: Lipoproteins Comparison

Lipoprotein	Main Function	Health Impact
Chylomicron	Transports dietary triglycerides from intestine to tissues	Neutral
VLDL	Transports triglycerides from liver to tissues	Can contribute to plaque formation
LDL	Transports cholesterol to tissues	"Bad" cholesterol; high levels increase heart disease risk
HDL	Removes cholesterol from tissues to liver	"Good" cholesterol; high levels reduce heart disease risk

HTML Table: Water-Soluble Vitamins

Vitamin	Main Function	Deficiency Symptoms
Thiamin (B1)	Carbohydrate metabolism	Beri-beri
Riboflavin (B2)	Energy production	Ariboflavinosis
Niacin (B3)	Energy metabolism	Pellagra
Folate	DNA synthesis	Megaloblastic anemia
Vitamin C	Antioxidant, collagen synthesis	Scurvy
Vitamin B12	Red blood cell formation	Pernicious anemia

HTML Table: Major Minerals

Mineral	Main Function	Deficiency Symptoms
Calcium	Bone and teeth structure	Osteoporosis
Iron	Oxygen transport	Anemia
Potassium	Fluid balance, nerve transmission	Muscle weakness
Sodium	Fluid balance, nerve transmission	Hyponatremia

Additional info: Some explanations and examples have been expanded for academic completeness and clarity.