Movement up or against a concentration gradient requires energy.
a. true
b. false

The unique structure of the neuron is dedicated to the efficient and rapid transmission of neural signals. the relationship between neurons, the spinal cord, and the brain constitutes an elaborate communication system throughout the human body. all but one of the functions listed below are a result of this interaction.

How does the diagram explain ocean currents? earth tilt 23.5 degreesquestion 1 options: earth's tilt causes uneven heating of earth which causes currents. earth's tilt causes the ocean to move because of gravity. earth's tilt and its rotation cause currents. earth's tilt causes uneven distribution of salt which causes currents.

Cathy hypothesized that corn would not grow in mud. to test this hypothesis, she took corn kernels and placed 5 in mud, 3 in soil, and 2 in water. to her surprise, the kernels in the mud grew faster than the kernels in the soil. what error might have caused these unexpected results? a. wrong hypothesis b. not enough variables c. undefined control d. too many variables