How do animals obtain the nitrogen they use to make proteins and nucleic acids?
a. by consuming plants or other animals
b. by absorbing ammonia from bacteria growing in the roots of plants
c. by breathing the nitrogen present in the atmosphere
d. by absorbing nitrogen found in the soil

Which of the following does not describe a physical property of iron? a iron is silvery-white or gray in color. b iron has a boiling point of about 3,000°c. c iron is a magnetic element . d iron and sulfur react to form iron sulfide.

Building glycogen from glucose molecules is an example of what

What can be said about farmers in highly developed countries? a) they have little or no negative impact on the environment. b) they practice subsistence agriculture. c) they are able to incorporate polyculture into their farming practices. d) they utilize organic farming techniques on a regular basis. e) they rely on large amounts of energy from fossil fuels.