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1. Science of Nutrition(0)

What is Nutrition
(0)

Nutrients
(0)

Macronutrients
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Micronutrients
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Fiber and Phytochemicals
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Energy in Food
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Nutrition as a Science
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Finding Credible Nutrition Information
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2. Tools for Healthful Eating(0)

Healthful Eating
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Three Guides to a Healthful Diet
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Dietary Guidelines for Americans
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Dietary Reference Intakes
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Food Labels
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3. The Human Body & Digestion(0)

Hunger, Satiety, and Hormones
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Overview of the Digestive System
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Organs of the Gastrointestinal Tract
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Accessory Organs
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Nutrient Absorption and Transport
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The Gut Microbiome
(0)

Disorders of the Digestive System
(0)

4. Carbohydrates(0)

Intro to Carbohydrates
(0)

Simple vs Complex Carbohydrates
(0)

Why Do We Need Carbohydrates?
(0)

Fiber
(0)

Carbohydrate Digestion
(0)

Dietary Guidelines for Carbohydrates
(0)

Alternative Sweeteners
(0)

Blood Glucose Regulation
(0)

Diabetes
(0)

5. Lipids(0)

Introduction to Lipids
(0)

Why Do We Need Lipids?
(0)

Fatty Acids
(0)

Digestion of Fats
(0)

Dietary Guidelines for Lipids
(0)

Cardiovascular Disease
(0)

6. Proteins(0)

Introduction to Proteins
(0)

Protein Structure
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Protein Synthesis
(0)

Why Do We Need Protein?
(0)

Protein Digestion
(0)

Dietary Guidelines for Proteins
(0)

Protein-Related Disorders
(0)

7. Vitamins(0)

Introduction to Vitamins
(0)

Fat-Soluble Vitamins
(0)

Water-Soluble Vitamins
(0)

Dietary Guidelines for Vitamins
(0)

Other Vitamin-Like Nutrients
(0)

8. Water and Minerals(0)

Water
(0)

Introduction to Minerals
(0)

Major Mineral: Sodium and Potassium
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Hypertension and Minerals
(0)

Major Mineral: Calcium and Phosphorus
(0)

Osteoporosis: Minerals and Bone Health
(0)

Major Mineral: Chloride, Magnesium, & Sulfur
(0)

Trace Minerals: Iron and Copper
(0)

Trace Minerals: Fluoride and Iodine
(0)

Other Trace Minerals
(0)

9. Alcohol(0)

Alcohol Consumption
(0)

Alcohol Metabolism
(0)

Short-Term Effects of Alcohol
(0)

Long-Term Effects of Alcohol
(0)

10. Energy Balance: Body Weight, Obesity, & Eating Disorders(0)

Healthy Weight
(0)

Energy Balance
(0)

Assessing Weight Related Health Risk
(0)

Factors That Influence Weight
(0)

Weight Loss
(0)

Maintaining Weight
(0)

Gaining Weight
(0)

Eating Disorders
(0)

11. Nutrition & Fitness(0)

Introduction to Physical Fitness
(0)

Exercise
(0)

Using Energy to Fuel Exercise
(0)

Nutrition & Physical Activity
(0)

Ergogenic Aids
(0)

12. Food Safety & Regulation(0)

Food Safety
(0)

Foodborne Pathogens
(0)

Foodborne Toxins
(0)

Food Preservation & Additives
(0)

U.S. Food Safety Systems
(0)

Natural, Organic, & Bioengineered Foods
(0)

13. Food Insecurity in the US and the World(0)

Food Insecurity
(0)

Global Food Insecurity
(0)

14. Nutrition: Pregnancy Through Infancy (0)

Preconception Nutrition
(0)

Nutrition During Gestation
(0)

Potential Complications During Pregnancy
(0)

Breastfeeding
(0)

Nutritional Needs for Infants
(0)

15. Nutrition: Toddlers to Late Adulthood(0)

Nutrition For Young Children (Ages 1-5)
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Nutrition For School-Age Children (Ages 6-11)
(0)

Nutrition During Adolescence (Ages 12-19)
(0)

Nutrition For Older Adults (Ages 50+)
(0)

4. Carbohydrates

Intro to Carbohydrates

4. Carbohydrates

Intro to Carbohydrates: Videos & Practice Problems

Video Lessons Practice Worksheet

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10 of 0

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Problem 10Multiple Choice

During photosynthesis, molecular oxygen (O2) is released as a byproduct. Based on the reaction stoichiometry and electron flow, which reactant is the primary source of the oxygen atoms found in O2, and what is the defining biochemical process that causes this release?

Carbon dioxide (CO2) is the primary source of oxygen atoms in O2 because fixation of CO2 directly ejects oxygen atoms as gaseous O2 during formation of sugars in the Calvin cycle.

Atmospheric O2 is recycled into O2 through a catalytic loop in chloroplasts independent of water and carbon dioxide, meaning photosynthesis does not alter water but only rearranges existing oxygen gas.

Water (H2O) is the primary source of the oxygen atoms in O2; the defining process is water-splitting (photolysis) during the light reactions that liberates O2 and electrons.

Both water and carbon dioxide contribute equally and randomly to the oxygen atoms in O2 because the photosynthetic electron transport chain exchanges oxygen atoms between CO2 and H2O without a preferred source.

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