Which of the following produced most of the oxygen that is found in the atmosphere today?

A living organisms

B outgassing

C condensation

D photodissociation

My gut is telling me B but I could be wrong ...

hypertonic, hypotonic, isotonic? "the concentration of the solute in the solution is lower than the concentration inside the cell"

Where is a subduction zone most likely to from?

How do large molecules like glucose enter a cell

Which organ is more suited for mechanical digestion of food?

What type of cells contains choloroplasts

What are the five evidences that a chemical change has taken place?

In frogs muscle tissue is usually grouped into large

after the brain receives information from the body's sensory receptors, what is the next step in responding to this information?

What does the endosymbiont theory explain about the origins of plant and animal cell

Suppose you have monohybrid pea plants in your garden and find that they produce round seeds to wrinkled seeds in the ratio of 3:1 if the alleles are designated R and r, respectively, what are the probable genotypes of the wrinkled seeds produced by