Which statements about electromagnetic or mechanical waves are true? Select all that apply. Light waves are mechanical waves.
Sound waves are mechanical waves.
Light waves are electromagnetic waves.
Sound waves are electromagnetic waves.
Only mechanical waves can travel through a vacuum.
Only electromagnetic waves can travel through a vacuum.

Which of the following describes a negative feedback loop? when the heart rate is too high, the body sends hormones that continually increase the heart rate higher. when a pregnant woman is in labor, the body sends hormones that increase the intensity of contractions, which then increases the secretion of the same hormones. when blood sugar is too low, the body sends hormones that raise blood sugar until it reaches a typical level and hormone secretion slows. when a person is jogging, the body sends hormones that continually decrease the rate of oxygen supply to the legs.

The cluster of developing cells from conception until birth is called an

To determine if a particular plant is homozygous or heterozygous, you would have to test cross with a