The overall amount of water on our planet has remained about the same for two billion years.

A sodium-potassium pump within a cell membrane requires energy to move sodium and potassium. the movement of glucose does not require energy. what is the movement of these materials

What are the four classes of cloud based on altitude? What does each prefix mean?

Which choice is an abiotic feature of an ecosystem? A) Dogs B) Ants C) Fungi D) Minerals

Which of the purely endocrine organs contain modified neurons that produce and secrete neurohormones? a. the gonads b. the pineal gland and the thymus c. posterior lobe of the pituitary and adrenal medullae d. only the adrenal medullae

These nonvascular plants were the first land plants from the paleozoic era. a. liverworts b. hornworts c. mosses d. merchantia

The fact that both green and yellow peas were produced by tall pea plants in predictable frequencies led mendel to propose the

What is a simple statement that predicts the result of a controlled scientific experiment? Question 1 options: Observation Hypothesis Conclusion Theory SaveWhat is a simple statement that predicts the result of a controlled scientific experiment?

One region of the world has both the highest birth rate and the highest infant mortality rate. which is it?

What does food supply all living things with for life activities?

An 8-year-old has scabs and fluid-filled vesicles on her face, throat and stomach. Three weeks earlier she had visited her grandmother who had shingles. What infection does the 8-year-old have