Unit 4 People in the Global Ecosystem

Chapter 14 - Feeding The World

Chapter 14.1 Human NutritionObjectives• List the major groups of nutritients and the

amounts of energy provided by each type.

Chapter 14.1 Nutrients

Two groups:

•Macronutrients – provide the body with energy.

Chapter 14.1 Nutrients (continued)

Two groups:

•Micronutrients – provide the body with small amounts of chemicals needed for biochemical reactions

Chapter 14.1 Calories

Macronutrients are measured in kilocalories (kcal) 1 kcal = energy to raise 1 Kg of H2O 1° C

kilocalories are commonly referred to as calories

Chapter 14.1 Three Types of Macronutrients

Three Types: • Carbohydrates• Proteins• Fats

Chapter 14.1 Carbohydrates

CarbohydratesA compound made up of carbon, hydrogen, and oxygen in approximately a 1:2:1 ratio

Provides ~4 kcal/gram

Complex

Carbohydrates

Chapter 14.1 Fats

Fats

Fats belong to a group of organic compounds called lipids.

A Lipid contains three long chains of fatty acids and is a main component of cell membranes.

Provides ~9 kcal/gram

Chapter 14.1 Proteins

Proteins

A large compound made of amino acids that provides the body with the construction material for making blood, muscle and other tissue.

Provides ~4 kcal/gram

Chapter 14.1 Amino Acids

Amino Acids

All proteins in the human body are made up of 20 different amino acids arranged in different patterns

Of the 20 the human body can make 12.The remaining 8 must be obtained from food – these 8 are called the essential amino acid.

Chapter 14.1 Animal vs. Plant Proteins

Foods from animals, including meats, eggs and dairy are high-protein foods with all the essential amino acids.

Drawback they tend to be high in saturated fats.

Plant Proteins are NOT complete . . . Unless!

Chapter 14.1 Animal Protein as a condiments

Reduce animal high-protein food to serving size of a condiment. with all the essential amino acids.

Combine it with plant proteins and complex carbohydrates.

Combine

Combine

Com

bine

ANY 2 = A COMPLETE PROTEIN

Chapter 14.1 Saturated vs. unsaturated

Fats belong to two groups.

•Saturated •Unsaturated You can tell how saturated a fat is by how firm it is a room temperature.

Current research suggests to avoid trans-fats

Also know as hydrogenated

Chapter 14.1 Nutritional Deficiency

Average human adult requires 2,500 calories/day.

People who receive < 90% of their energy needs are considered undernourished.

Malnurtrition is when people receive their energy needs but lack a specific nutrient.

Chapter 14.2 World Food Supply

Objectives• Explain the effects of economics on the

production of food.

Chapter 14.2 Green Revolution

The Green Revolution began in the mid-1960s with the development of new strains of wheat and rice, the two main foods of the world.

Chapter 13.2 Cash Crops

A cash crop is a crop grown for the purpose of export sale.

In many developing nations 85% of the

farmland is owned by 5% of the population.

In Africa, rather than growing food – grows feed crops for

European livestock.

Chapter 14.2 Food from Water

Commercial production of fish in a controlled , maintained environment is called aquaculture.

Maine Salmon Aqua-culture

Chapter 14.3 Modern Farming Techniques

Objectives• Describe how farming

techniques have changed during the last 50 years.

Chapter 14.3 Historically Farming

Farming techniques have historically been very labor-intensive.

Chapter 14.3 Changes in Farming

Large pieces of equipment that use fossil fuels replaced animal and human powered tools.

Chapter 14.3 Agribusiness

Today 2/3 s of the food produced in the U.S. comes from fewer than 50 agribusinesses.

Some of the same corporations also produce 75% of the pesticides and other chemicals used by the

industry. of the food produced in the U.S.

Chapter 14.3 Monoculture

Many farms that used to grow a variety of crops shifted towards growing ONLY one or two crops.

By growing one genetically identical crop the plants

are more vulnerable to disease.

Chapter 14.4 Sustainable Agriculture

Objectives

• Describe the basic components of sustainable agriculture, and explain why they are desirable.

Chapter 14.4 Sustainable agriculture

Also called regenerative or organic farming, sustainable agriculture is based on crop rotation, reduced soil erosion, pest management, and a minimal use of soil additives.

Chapter 14.4 Crop Rotation

Helps prevent soil from becoming depleted in mineral nutrients, such as nitrogen.

Crop rotation means changing the type of crop grown on a regular cycle. (Usually 1 to 6 years).

Chapter 14.4 Reducing Erosion

Strip Farming - a good plan is to establish a tree (or grass) belt along the edge of every second strip

Chapter 14.4 Pest Management (IPM) Integrated pest management - reduces the use of

pesticides by incorporating natural predators of pest organisms.

References

Wiley. "Non Sequitur." Cartoon. gocomics. 15 Sept. 2006. 17 Sept. 2006 <http://www.gocomics.com/nonsequitur/2006/09/15/>.

Earth Science Geology, the Universe and the Environment. Glencoe, 2002. PDF Version. 17 Sept. 2006. p. 23