When does the cell have to use active transport? A. when the cell is low on energyB. when the cell is in a highly concentrated solutionC. to move molecules across the membrane quicklyD. to move molecules across the membrane against a gradient

The female reproductive system in humans differs from the human male reproductive system in that only the female system is responsible for A. producing sex hormones. B. producing gametes C. creating offspring. D. nourishing a developing zygote.

Which condition causes fatty substances to build up in blood vessels?

The amount of energy that a food contains can be measured by vitamins. a. True b. False

What stone faced animal was all the rage in 1970?

If Emily's parents decided to have another child, what would the genetic counselors have told them about their probability of having a second child with CF.

What is natural gas

A reaction in which products can react to re-form reactants is a. reforming b. reversible c. buffered d. impossibnle at equilibrium a. the forward reaction rate is lower than the reverse

Why is it so important to be ethical in conducting the scientific method process?

How did Mendel make crosses with his plants? A., He planted the seeds of each type together, and they grew into a single plant. B., He cut the peas in half and combined them to grow a single plant. C.

Marissa is studying the solar system. which object in the solar system is a star? A. the sun B. saturn C. Earth's moon D. a comet