Water perpetually cycle's from the earth to the atmosphere and back. In the previous sentence what does perpetually mean?

A. constantly

B. frequently

C. occasionally

D. rarely

Why do the heads of the phospholipids move to the inside and the outside of the cell and the tails move inwards towards each other?

Which is a trait of an index fossil? A. Resembles a living species B. Found in a limited area C. Found in a limited time span D. A particular kind of organism

All growth of a flowering plant takes place within specialized tissues called

Give the mechanism of control and co-ordination in animals and plants.

What do scientists already know about the bottom of the ocean?

Most glaciers in Alaska are retreating, although the average annual snowfall has increased in the last few decades. What does this tell us about what is happening to sea-level temperature?

Jessi consumes a diet of 1920 total kcalories that has 80 g of fat. what percent of jessi's diet comes from fat? (give answer to the appropriate reporting digit. only give the value. do not include the term percent or its abbreviation.)

Scientists break down evolution into catogories

The process of sediments being compacted and cemented to form sedimentary rocks is called A. metamorphism. B. deposition C. crystallization D. lithification

What is presumptive identification of a microorganism?