Why is nitrogen necessary for living organisms

There are 4000 units of energy available to grass at the first trophic level of an ecosystem. if the grass is eaten by a mouse and the mouse is eaten by an owl, how many units of energy will be left for the bobcat that eventually eats the owl?

What was Rudolph Virchow's contribution to the cell theory? A. He concluded that cells come from preexisting cells. B. He concluded that cells are the basic units of structure and function of all living things. C.

In an experiment designed to test the effect of temperature on goldfish respiration, the temperatures that were changed represent what type of variable? A. control B. responding C. experimental D. correlative E. placebo

Which of the following statements is a true effect of declining biodiversity? Group of answer choices a) Medical and pharmaceutical researchers will be able to bank DNA from extinct species.

which quality would make the question " what will make coed produce more milk "? a good scientific question for a biologist to investigate

Energy flow through an ecosystem is one-way because

6. Which unit is used to measure sound intensity? A decibel B watt C meter D foot

In the deep waters of the ocean, coral reefs are found in abundance. Algae live on these coral reefs, providing nutrition and producing pigments that give color to the corals. The corals offer shelter to the algae. So, they share a association.

Dna amplification requires

a scientist observing an onion cells and a human cheek under a microscope which observation does she most likely take