Simple Carbohydrates

Download Report

Transcript Simple Carbohydrates

Feeding the World
Chapter 14
14.1 Human Nutrition

humans need energy to carry out life processes




Growth
Movement
Tissue repair
humans are omnivores because they consume plants and animals
NUTRIENTS
Macronutrients

provide the body with energy

measured in kilocalories
(calories)

carbohydrates

proteins

fats
Micronutrients

provide the body with small
amounts of chemicals needed
in biochemical reactions

Vitamins

Minerals
Carbohydrates - source of
energy
Complex
Carbohydrates
Simple Carbohydrates

Sugars

Starches

absorbed quickly

steadier, long-lasting energy

provide immediate energy
Protein
 contains
 NOT
amino acids (organic molecules that contain nitrogen)
recommended as a major source of energy
 provide
the building blocks that make up most body tissues
(muscles, blood, skin, enzymes)
Essential Amino Acids

must obtain 8 from foods
Animals

because some plants lack EAA,
vegetarians should eat a
combination of grains and
legumes

Meat

Eggs

dairy
Plants
 grains
(wheat, rice, corn)
 legumes
(peas, beans, peanuts)
Fats (Lipids)


Phospholipids – principle
components of cell membranes
provide more than twice the
amount of energy per gram as
carbohydrates and proteins
Solid Lipids
 Fats
 butter
and lard
Liquid Lipids
oils
Vitamins and
Nutritional Deficiency
malnutrition
Minerals
micronutrients
is caused by a lack
of a specific nutrient
14.2 World Food Supply

the food increase is a result of:



advances in agricultural practices
improvements in crop plants
traded with prices driven by economic factors
GREEN REVOLUTION

uses modern farming methods and machinery for planting,
maintaining, and harvesting

resulted in a large increase in food production without a large
increase in land usage

Not available for farmers in developing nations:



did not have the water needed
no money to buy fertilizers, fuel for machines
poor farmers received less money for their crops
CASH CROPS

crops grown to be exported to other nations for higher prices

produce more profit than if grown for local consumption

less locals are fed
FOOD FROM THE WATER

Increased harvesting of ocean fish has led to endangerment of fish
species

environmentalists believe we have exceeded the limits of safe harvest in
the ocean
Aquaculture – controlled commercial production of fish and mollusks
 alternative
 provide
to fishing in the open ocean
much of the protein consumed by people around the world
14.3 Modern Farming
Techniques

changes occurred in the middle of the 20th century
Industrialized Agriculture

human powered tools were replaced by large pieces of farm
equipment powered by fossil fuels (fewer workers)

largely increased the number of people each U.S. farmer could
feed

requires large inputs of energy, pesticides, and fertilizers

Run by agribusinesses (control stages of food production,
packaging, and transport)

Use of pesticides:

Increase in resistant insects and other pests
Monoculture

Growing only one or two crops that commanded the highest prices




Produced large numbers of genetically identical crops
All the plants are vulnerable to the same diseases
Depletes the soil of mineral nutrients needed to grow the crop
Reduces soil fertility
14.4Sustainable Agriculture

modern agriculture is driven by
economics and international
trade
Competition has resulted in:

soil erosion

deforestation

desertification

hunger

war

global environmental damage
Sustainable Agriculture
Regenerative Farming
 to
minimize the impact that food production
has on the environment
 based
on crop rotation, reduced soil
erosion, integrated pest management, and
minimal use of soil additives
Sustainable Agriculture

Reducing erosion: soil
management and careful irrigation
Sustainable Agriculture
Crop rotation: changing the type of
crop grown in an area on a regular
cycle
 Helps prevent depletion of mineral
nutrients in the soil
Sustainable Agriculture
Pest management:
 Integrated pest management
(IPM)
 Reduces the use of pesticides
 Makes use of natural predators
of pest organisms