Download File - Environmental Science

Name: _____________________________________________ Period: ____________________ Date: __________________________
LT 7B Active Practice Key
1. Define food security and food insecurity.

Food security means having enough food to meet basic nutritional needs. Food insecurity not
getting enough to eat and—living with chronic hunger and poor nutrition.
2. What is the root cause of food insecurity?
• Most agricultural experts agree that the root cause of food insecurity is poverty, which prevents
poor people from growing or buying enough food. Other obstacles to food security are
environmental degradation, political upheaval, war, and corruption.
3. Distinguish between chronic undernutrition (hunger) and chronic malnutrition and describe
their harmful effects.


People who cannot grow or buy enough food to meet their basic energy needs suffer from chronic
undernutrition, or hunger. Many suffer from mental retardation or stunted growth or die
prematurely from infectious diseases such as measles and diarrhea, which rarely kill children in
developed countries.
Many of the world’s poor can afford only to live on a low-protein, high-carbohydrate, vegetarian
diet consisting mainly of grains such as wheat, rice, or corn causing chronic malnutrition—
deficiencies of protein and other key nutrients. This weakens them, makes them more vulnerable
to disease, and hinders the normal physical and mental development of children.
4. What is a famine?

A famine is a severe food shortage that can result in mass starvation, deaths, and social
disruption.
5. Describe the effects of diet deficiencies in vitamin A, iron, and iodine.
• Lack of vitamin A can cause children younger than age 6 to go blind each year and double
chances of dying within a year. Having too little iron causes anemia which results in fatigue, makes
infection more likely, and increases a woman’s chances of dying from hemorrhage in childbirth.
Chronic lack of iodine prevents proper functioning of the thyroid gland, which produces hormones
that control the body’s rate of metabolism, and can cause stunted growth, mental retardation, and
goiter—a swollen thyroid gland that can lead to deafness.
6. What is overnutrition, and what are its harmful effects?

Overnutrition occurs when food energy intake exceeds energy use and causes excess body fat.
Too many calories, too little exercise, or both can cause overnutrition. People who are underfed
and underweight and those who are overfed and overweight face similar health problems: lower
life expectancy, greater susceptibility to disease and illness, and lower productivity and life
quality.