What are the two main categories of ecosystems?

a.

effective and ineffective

b.

marine and freshwater

c.

biotic and abiotic

d.

aquatic and terrestrial

The amount of matter changes when water changes from a liquid to a solid. True or false

The chart shows information about three different embryos early in their development. Which is best supported by the information in the chart? Species X and Y are not related to humans. Species Y and Z are not related to humans.

Why is secondary succession achieved more quickly than primary succession?

Which characteristics used to classify galaxies

Multiple Choice Earth Science Question and Answer! Q: The effects of Erosion by a Continental glacier can be compared to the actions of a ... a. cement mixer b. bulldozer c. ditch digger d. auger

Magma from Earth's interior is this from the cracks at mid-ocean ridges true or false

Through aquatic succession, a clear lake may eventually become

List four types of evidence used to organize organisms in systematic taxonomy

Oxygen (O) atoms have six valence electrons and beryllium (Be) atoms have two valence electrons. Which of the following is the correct formula for a compound made of oxygen and beryllium?

The presence of cholesterol in the plasma membranes of some animals (A) enables the membrane to stay fluid more easily when cell temperature drops. (B) enables the animal to add hydrogen atoms to unsaturated phospholipids.