Why are vestigial structures not removed by natural selection? A. Vestigial structures are genetic traits.
B. They provide a competitive advantage.
C. Only unimportant structures can be removed,
D. Natural selection removes only harmful traits,

What food can provide the body with a quick source of the energy needed to carry out cell functions (a) whole grain bread (b) ground hamburger (c) vegetable oil (d) whole milk

Darrel conducted an experiment with the following procedure: fill two cups with ice water. place an uninflated balloon snuggly onto your left index finger. blow a little air into an identical balloon, and place it onto your right index finger. place both fingers into the cups of ice water. darrel noticed that his right finger felt warmer in the ice water than did his left finger. which of the following does the experiment show? a. air is a good radiator of heat. b. air is a good insulator of heat. c. air is a good conductor of heat. d. air is a good convector of heat.

Plants consume most of their carbon from a. the soil b. the water c. the roots d. the air