How is an electromagnet different from a permanent magnet?

A. It has only north magnetic poles.

B. It has only south magnetic poles.

C. There is no magnetic field.

D. It can be turned on and off.

How to prevent bias in scientific investigation

Many molecules are moved through the body by what? A. carbohydrates B. lipids C. nucleic acids D. proteins

What organelles release energy from sugar?

Two different trees have been classified as Pinus pinea and Pinus nigra. Which of the following statements is correct? A. Both trees belong to the same class but a different genus. B. Both trees belong to the same family and same genus. C.

Organic compounds are commonly called

According to the activation-synthesis theory of dreaming, the source of a dream is neuronal firing in

A mother sleeping in the middle of the night nevertheless responds when she hears her 2-year-old daughter crying in the adjacent bedroom. This indicates that the mother possesses:

How can farmers keep topsoil on their land? check all that apply. a. close their gates b. keep plants growing c. plant trees to shield fields from the wind d. do not plow when extremely heavy rains are expected?

Measures how much matter is present in a substance

How is artificial selection similar to natural selection?